car problem (real head scratcher)

[Battis]

My 2005 Lincoln Towncar (104,000 miles) bucks at approx. 40 MPH when I give it the gas. No codes show up. If I turn off the overdrive it doesn't happen.
Trusted mechanic said it's probably the transmission (he described what he thought was the problem).
Transmission guy said it sounds like a misfire.
Any ideas?

[35isit]

Have someone with the proper scan tool figure which coil is dropping out.

[Battis]

That's the problem - no codes are showing up.

[colt38sp]

Sounds like the Torque Converter. I had this happen once on a F-150 and all it needed was a fluid/filter change and problem went away. I am no mechanic though.

[Plate plinker]

Your halfway there. By turning off the overdrive you have in my non mechanic mind proved it is the transmission. Seems it could be the torque converter lock up get flaky. Find a better transmission guy.

[35isit]

That's the problem - no codes are showing up. It doesn't have a bad enough miss to turn on check engine light. A scan tool that shows what each cylinder is doing will show which one or (ones) are dropping out under stress. When you turn off overdrive there is not as much stress on engine.

[nvbirdman]

I think maybe the reason you're not getting an engine code is because the problem is not in the engine. Check the transmission.

[popper]

Could be either. Torque converter is 'locked' when in overdrive - had that happen on a couple autos. Solenoid in trans. controls it. Over-run clutch in converter will cause it to buck when slowing down to stop - won't unlock usually due to crud in the clutch. Could be low engine torque 'lugging' in OD or computer not dropping OD when lugged. Yup, need scan tool while driving (loaded).

[s mac]

I'm a Ford tech, and agree that it's probably a misfiring coil, in overdrive, 50-60 mph especially on an upgrade is often when the miss shows up. Need a scan tool to test drive running power balance. Those often won't set a dtc.

[Battis]

The mechanic took it out with the scan tool and it didn't show anything when it happened. He thought it might be the solenoid in the transmission, especially at that speed (40 mph), and especially when I turned the OD off. The transmission guy said (on the phone) it could be, but it might be a misfire, too. The car does have a history of bad coils but they usually show up on the scan.
So...am I doing any harm by driving with the OD shut off? Other than bad gas mileage.

[skrapyard628]

Just from what you stated I would really be led to believe the torque converter clutch is not unlocking properly. Could be the solenoid for it, could be the clutch itself is sticking, or even possibly the wiring.

Most generic scan tools wont allow you to monitor the TCC solenoid for on/off function while driving or at all. They usually will only post a code if the solenoid is completely burned out (open circuit) or there is a break in the wiring harness for it (once again, open circuit) And Im unsure if the system on that vehicle even allows you to monitor the TCC with the proper Ford scan tool (maybe someone here knows Ford scanners better and can say).

I had the same issue on an '02 Nissan Frontier. I replaced the torque converter clutch solenoid and checked all the wiring for it while I was down there. Problem fixed.

If you end up replacing the TCC solenoid you usually have to remove the drain pan for the trans. Obviously if the pan is off you might as well put a new filter in and give it some fresh trans fluid while youre in there.

[Battis]

I'm heading to the transmission place now. The guy is good - he replaced a clutch in a Jeep Eagle Summit for me many years ago when no one else could, or would, do it.
Thanks for the tips. Now I know what questions to ask.

[Handloader109]

Lincoln.... Ford product. Does it have individual Coils on each sparkplug? If so, then one or more is going bad. Won't throw code unless they fail entirely.
I've a 2005 Ford truck that I thought was the tranny, but it was bad coils.

[Finster101]

Do a complete exchange of the trans fluid. The "washboard" effect should clear up. It's a very common Ford issue, if your trans guy didn't know about it find someone new.

[35isit]

I'm a Ford tech, and agree that it's probably a misfiring coil, in overdrive, 50-60 mph especially on an upgrade is often when the miss shows up. Need a scan tool to test drive running power balance. Those often won't set a dtc. Ford parts department for 25 years. Probably sold 500 coils for that problem on Lincolns, Crown Vics and pickups. That's why I posted what I did. Worked with a technician once who always priced the job to replace the "bad ones" and all of them. He said it will be back sooner or later for the rest. By putting in all of them you were just heading off future repairs.

[Battis]

I never made it to the transmission place. I got on the highway and it started bucking even with the OD off. I went back to the trusted mechanic (I really do trust him) and he said we're back to the bad coil that's not bad enough to set the code light off (as 35isit and smac said). I asked if it's worth it to change all 8 coils and he smiled and said it was worth it to him. It's happened in the past - the engine light won't come on until the coil is completely gone. Luckily I only need the car for around town driving.

[brass410]

I'm with starmac, you probably have, A-bad coil or B the boot that covers the coil to plug area is starting to breakdown, sometimes there's only one, others it can be all 8. I see this a lot here in the shop, when it gets real bad, it will show as a random misfire, when you remove the coil take a real close look at the coil on plug boot sometimes you can see carbon tracking on them.

[Brassduck]

103000 miles, I'd put a set of plugs in it first.

[osteodoc08]

Get a scan tool. See which cylinder is misfiring. It’s not frequent enough to throw a code. You can use one for free at autozone or similar. This is typical symptoms of fords COP when they’re going bad. You’re due for plugs. Those 4.6L and tranny combos in the town car are pretty solid

[6bg6ga]

I hate to disagree but I would have a Ford technician with a Ford diagnostic tool or a really good mechanic with a Mac diagnostic tool check it. The cheap diagnostic tools at the parts stores are gunk for the most part. Misfiring? The "Good" scan tool should have shown misfires a count of the misfires for example on cylinder #1 XXX misfires at least good scan tools do. My experience ....Ford is notorious for torque converter problems and they will manifest themselves as kind like a miss. I went thru (4) torque converters on (4) different Ford F250 vans.

It was mentioned 103,000 miles a set of plugs. I went 180,000 miles on a set no misfires.

My GMC Envoy had a slight miss that didn't set a code but the Mac scan tools showed how many times it missed on the affected cylinder. So, it doesn't always set a code. Narrowed my problem down to a intermittent coil pack which I changed and problem was gone. I'm a firm believer in not throwing parts at something. The problem needs to be found and then replace the part. As for throwing all new coil packs on it ...... I wouldn't because your probably looking at $80 ea on up.

[Ford SD]

My 2005 Lincoln Towncar (104,000 miles) bucks at approx. 40 MPH when I give it the gas. No codes show up. If I turn off the overdrive it doesn't happen.
Trusted mechanic said it's probably the transmission (he described what he thought was the problem).
Transmission guy said it sounds like a misfire.
Any ideas?


Low cost temp fix is to pull each if the 8 plugs off the coils one at a time and use a small fine (clean oil free) 1/4 x 1/16 flat file and clean the corosion off the top and bottom of the contacts ... compressed air to clean up and reinstall
I have also seen where the top of the coil is cracked and moisture can get in

Most likely the ones closest to the edge of the hood is bad... water drips down

Better fix ..Go to Rockauto

Best place for 8 new coils plus
8 new plugs

it woulds happen to the ford superduty I was driving ... bad coils if you replace all 8 you should be good for another few years

[Battis]

I hooked up my high tech OBD2 scanner (from Amazon) after it ran really bad and it showed PO303 - cylinder misfire. Little bugger.

[s mac]

There you go.

[6bg6ga]

Low cost temp fix is to pull each if the 8 plugs off the coils one at a time and use a small fine (clean oil free) 1/4 x 1/16 flat file and clean the corosion off the top and bottom of the contacts ... compressed air to clean up and reinstall
I have also seen where the top of the coil is cracked and moisture can get in

Most likely the ones closest to the edge of the hood is bad... water drips down

Better fix ..Go to Rockauto

Best place for 8 new coils plus
8 new plugs

it woulds happen to the ford superduty I was driving ... bad coils if you replace all 8 you should be good for another few years

I still question the legitimacy of replacing all 8 coils. In my Envoy I knew I had a bad coil per the scan tool and replacing the plug to find the miss still there. It was a simple matter to replace the offending coil at $80. I replaced number 1 and 2 simply because the record indicates they are the ones that have a problem on the inline 6.

Ford's generally have a problem with the coils that get dripped on from the AC line/moisture/ condensation. I went thru (4) Ford vans in 20 years so I can tell you which cylinders coils are subject to having to be replaced because Ford never corrected the situation in all that time. Anyway there are 2) coils that go to hell as a result of drippage from the AC lines. IN ALL the time I drove the Fords I never lost any other coil pack thus the reason to question the replacement of all eight coil packs. I drove each Ford van to almost 300,000 miles and I lost the two coil packs on each of the Ford vans the same two. I can see the eight plugs since you are going to the bother of working on it anyway.

Good for you on your Amazon scan tool generally the cheap ones are prone to showing questionable codes.

[Battis]

If I could do the work myself, I'd probably do all 8. Since we got the Buick, the Lincoln is #2 car and not driven much. I just got rid of my 2001 Lincoln Towncar with 227,000 miles on it. Lincoln Towncars - they've been called bookie cars, pimp mobiles, and just old people cars. I call them comfortable as heck.

[brass410]

how about that ? misfire did it give a specific cyl or just misfire? if you have a shop/mech that you trust they can scan with a live data scan and it will show specifics like cyl or random misfire counts, this will help narrow down specifics. As to replaceing plugs it would probably be a good idea as some of these engines are notorious for seizing plugs at high mileage making a tune up into a cyl head replacement job, we just love it when guy's come in bragging how long they went ( without at least pulling plugs for inspection) because the owners manual says you can, job goes from a couple hundred dollars to several thousand. Technically they don't sieze rather they get a heavy coating of carbon on the tip causing it to break off in the cyl head. If you find which cyl has misfire (if just one) you can trade coil with nieghbouring cyl and see if misfire moves to new cyl(will still need scan tool) if it does its probably the coil if it doesn't its more likely the plug.

[6bg6ga]

how about that ? misfire did it give a specific cyl or just misfire? if you have a shop/mech that you trust they can scan with a live data scan and it will show specifics like cyl or random misfire counts, this will help narrow down specifics. As to replaceing plugs it would probably be a good idea as some of these engines are notorious for seizing plugs at high mileage making a tune up into a cyl head replacement job, we just love it when guy's come in bragging how long they went ( without at least pulling plugs for inspection) because the owners manual says you can, job goes from a couple hundred dollars to several thousand. Technically they don't sieze rather they get a heavy coating of carbon on the tip causing it to break off in the cyl head. If you find which cyl has misfire (if just one) you can trade coil with nieghbouring cyl and see if misfire moves to new cyl(will still need scan tool) if it does its probably the coil if it doesn't its more likely the plug.

My experience here....The cheap scan tools don't do everything the better ones do. I've encountered random codes on the cheap scan tools that were checked against a decent scan tool. I will admit it is possible to purchase a scan tool that actually works correctly without throwing random codes. I will admit I don't own one and I count on my son who is a GM master world class tech to bring his scan tool to check my vehicles. There was an instance where the Caddy threw a code and I had it checked by the local parts house and then checked with my son's Mac scan tool. The Mac told me exactly the sensor that was faulty and the parts house threw a random mixture code.


As for the spark plug mileage ..... My instance I was a technician that spent hours on the road everyday thus it took quite an undertaking to get the van into a shop to get repaired. My comment on the miles wasn't necessarily to encourage others to exceed the 100K general spark plug life. My experience here again based on my vehicle and the company van I drove is the plugs generally come out easy up to about 120K miles and after that difficulty starts to set in. In my instance my former boss didn't care about getting a vehicle in at say 80K to change plugs because every hour I was off the road he lost $100 in revenue therefore he probably figured that $300 down the road to change plugs when my schedule was less booked was better than say a $80 bill to change plugs when I was booked solid.

I keep a spare GM colil for the Envoy and the SRX on the shelf as a backup for my misfire problems that might arise in the future and I wholeheartedly agree with switching the suspected bad coil with another coil in tracking the misfire and as mentioned a scan tool is needed in order to see if the fault followed the coil. Glad you got it figured out at any rate.

[Battis]

The reason I trust the mechanic is that he's not a parts swapper. There are others in town that just replace parts until they find the problem. The Lincoln had a bad coil last summer and it eventually showed on my scanner, and it was confirmed by the mechanic. He replaced it, and it's been fine.
The code on the scanner I used read PO303, which indicates a misfire in that cylinder. It's going to the shop tomorrow and they'll confirm it before replacing it.

[dangitgriff]

https://uploads.tapatalk-cdn.com/20200226/667ca4b631610ae2853d5080e705ec6f.jpg

[Battis]

The last car thread I started was about the tires on my Buick, which is apparently the worse car to own. I'm curious to see if this thread takes off like that one did.

[merlin101]

My 2005 Lincoln Towncar (104,000 miles) bucks at approx. 40 MPH when I give it the gas. No codes show up. If I turn off the overdrive it doesn't happen.
Trusted mechanic said it's probably the transmission (he described what he thought was the problem).
Transmission guy said it sounds like a misfire.
Any ideas?

Fuel pump! It's electronic and in the fuel tank, been down that road a couple times and was also told it was the tranny. After checking the fluid and seeing the color and no brunt smell I checked the fuel pressure and it was fluctuating, new pump fixed everything.

[6bg6ga]

The last car thread I started was about the tires on my Buick, which is apparently the worse car to own. I'm curious to see if this thread takes off like that one did.

Want to dig up the Buick thread again? :kidding:

[Battis]

Nope. New tires, no problems, love that Buick.

[Finster101]

The last car thread I started was about the tires on my Buick, which is apparently the worse car to own. I'm curious to see if this thread takes off like that one did.

Nope, I'm a GM tech but I like Town Cars. My Dad had several of them over the years and I had an 03 Mercury Marauder. All were prone to TCC shudder if the trans fluid wasn't changed about every 50k or so. Very common, hence my suggestion to have it done. Hard to diag over the internet though since often several problems can present with the same symptoms. Kinda like them TV preachers trying to swammy out your ailments and heal you at home for a small contribution.

[skeettx]

Waiting on the final answer
Good luck
Mike

[rdwarrior]

I had a similar problem with my 200 Ford F-150 a month ago. I also thought it was the transmission as it didnt act up with overdrive turned off. I changed the plugs and rebuilt the coil packs. runs like a dream again. It was misfiring, but with over drive off, it kept the rpms up so it didnt act up, making me think it was the transmission. change the plugs and rebuild the coil packs and I would be willing to bet all your problems go away.

[tomme boy]

I worked at Autozone part time last year for something to do. DO NOT GET YOUR PARTS FROM AUTOZONE!!!

If it is a Autozone branded part go something else. Look for name brand on your parts. I got so mad at all the junk that they sell that I was telling people to go somewhere else if i could not get a name brand part. Like TRW, MOOG, Bosch...... Some of the cheaper batteries would fail in a few days. You have to buy their most expensive store brand to get a good one. Alt, starters, coils, sensors, lots and lots bad right out of the box.

Granted, they will keep replacing the parts till you get a good one. But who wants to go through that? I had to quit as I could not take the rip offs anymore.

The code reader is a very basic thing and is meant to sell you parts. It only gives basic codes. It will not tell you what coil is bad or how many misfires it had. Most of the time you could not even clear the codes for the customer. I finally opened up one of the $500 readers they try to sell and started to use that instead. I am not a rich guy and I was trying to help people that did not have the extra $ to waste. I have been there. It is not fun to know you are going to loose your job because your car broke down.

[kens]

I had a 2000 Crown Vic, and had the same described issue with spark plug coils packs. I replaced them myself, no big deal.
Also, there was a run of intake manifolds that developed a oil leak that flooded the spark plug boots with oil, the rubber boot broke down and caused issue.
I bought the new type manifold ($250) and replaced it myself, a whole days project.
you may want to check if your car falls into the bad oil leaky manifold production run.

btw, I drove that car for over 15 years, 250,000 miles, was still running good when I sold it,
whether it was a old mans car or not, it ended up being the most economical car to drive for the 'total cost of ownership'
total cost of ownership is purchase + fuel + maintenance + tires + brakes + insurance + resale divided by years of use = total cost

[Battis]

Two jobs I had sold me on the big cars. I was a cop and I loved the Crown Vics. Then I drove a limo part time and was sold on the Towncars (like driving in your living room). I put some weight in the trunk of the Towncar during the winter and it goes just about everywhere I want to go.
One time I tried to stop a stolen Mustang 5.0 at night on the highway and the chase was on. I was doing about 120 mph (90,000 miles on the cop car) and the kid in the Mustang turned off his headlights and was going about 135 mph. I felt foolish so I turned off the pretty lights and went home.
That would have been a great Ford commercial.

[Handloader109]

Coils. Yes, replace them all if they haven't been replaced in the past 3 or so years. They break down, all of them, the cheap ones and the OEM ones. BTW, how do you determine which is failing at load with NO codes being thrown? YOU CAN'T..... Replace them all, Or do one at a time and HOPE you are getting the right one. BTW, it could be a couple.

[brass410]

waiting for final outcome, its fun trying to fix stuff you cant see, hear, or test hands on. Sometimes the replies are stuff that never would have occurred to me/how come I haven't seen that? To just wild guesses that are totally vague, always interesting.

[Battis]

I got a code yesterday. PO303 misfire.

[Lloyd Smale]

yup I agree. that's about the speed when most torque convertors lock and unlock and when you put it in drive instead of od the convertor doesn't lock.
Sounds like the Torque Converter. I had this happen once on a F-150 and all it needed was a fluid/filter change and problem went away. I am no mechanic though.

[6bg6ga]

I got a code yesterday. PO303 misfire.

I realize you've gotten a lot of shade tree mechanics here offering advice some have absolutely no idea and some have some experience. Most have offered the advice to blanket change all the coil packs and I guess they believe money grows on trees but I don't. There are several different grades of parts I know because I have purchased everything from GM/Delco to the plain white paper or cardboard box with parts inside. Sure, in a perfect world where money grows on trees it would be nice to replace ALL the coil packs and simply throw parts at it in the hope that the problem simply won't come back. I guess if you have the money to just throw around then replace them at a cost of around $800 or so for the "GOOD" parts. Now, someone is going to chime in after I post this and tell you that oh no you can get these on line for $50-100 for a set of eight. Been there done that and all it did was make me work harder replacing coil packs in 3 to 6 months as the cheap ones simply don't hold up. This is kinda like buying a wheel bearing hub assembly from GM for $450 verses buying a white box unit 2for $70. The white box unit surely is priced attractively but for some odd reason goes out the first time you go thru a water puddle or a snow drift. You get what you pay for period. You do what you want but for my experience since I've tried it all I'll buy the expensive coil pack and replace it once verses buying the cheap set and replacing two or three a few months down the line. There is really no point (my opinion here) of replacing coil packs that don't have a problem. As I mentioned also on the Ford product with that engine you will sooner or later replace two coil packs the result usually of the AC condensation dripping on them. But hey what do I know? I had to drive Ford Vans for 26 years and I could publish a book on every single engine flaw and malfunction your going to see on one. Nuff said.

From Lloyd Smale
yup I agree. that's about the speed when most torque convertors lock and unlock and when you put it in drive instead of od the convertor doesn't lock.

Its a hard problem to find since the converter problem manifests itself as a type of miss when it tries to lock up and there is a problem with the torque converter. Like I mentioned in a prior post I went thru this in a number of Ford F250 vans and personally saw the converters and bearings that were taken out of the transmissions of the vehicles I drove. At the time I advocated the process of pumping new fluid in the tranny to thoroughly clean out the torque converter and transmission internals. Several times I snuck this past the boss and got it done to my vehicle and I was able to get over 250K miles out of the transmission before it needed rebuilt. The last tranny I got only 120K out of it without the tranny flush.

[Battis]

How big a job is it to replace the torque converter? I'm looking ahead in case it still acts up after I have the coil changed. With my l luck it'll be the coil(s) and the converter.

[6bg6ga]

How big a job to replace the torque converter? Its not a big job it requires that you can jack the car up borrow a transmission jack or floor jack for the transmission unbolt the transmission, drive shaft, necessary transmission lines and cables harness and so forth. The problem lies in the fact that there is going to be some metallic debris from the wear in the converter. This will be circulated thru the transmission so a complete flush would be the minimum I would suggest besides a new torque converter. The best solution would be a rebuild of the tranny if needed or possibly a trade for a rebuilt reconditioned transmission.

[s mac]

Torque converter swap not too bad once you have the trans pulled out. Pretty substantial job. Replace the #3 coil and I think you will be good.

[Finster101]

If you still have the problem after changing the coil since it sounds like that's what you are going to do, replace the fluid in the trans before putting a converter in. Again trying to diag it over the internet is always a guessing game but I have been turning wrenches professionally for over thirty years so I'm not just pulling something out of the air here.

[rdwarrior]

Instead of buying new coil packs, just buy the rebuild kits. The rebuild kits only cost about $5-6 each. that replaces the rubber boot and the wire spring that makes the connection to the spark plug. Easy job to do and not that cost prohibitive.

[jimlj]

Replacing a torque converter is simple, ONCE you have the transmission out of the car. Getting the transmission out of the car is not simple.

[firefly1957]

I am glad you found the issue I had a 2009 Grand Marquis with a coil that missed in wet weather it never showed except my fuel economy went south I had two dealers look at it they found nothing One warm day I had enough and drove it until warm then spayed the running engine down with a hose the engine did not stutter but driving around the block (10.25 miles) I went from 26 to 18 MPG . I said the heck with it and sprayed all the wires and boots with silicone and never had the trouble again ( I did repeat it annually).
At 94,000 miles I changed the plugs and found where water was getting under a coil into the area of the spark plug. I sealed everything good with dielectric grease sold the car shortly after that .
We replaced the Mercury with a 2017 Chevy Equinox 4 cylinder it got poorer fuel economy then the big Mercury !
The equinox was also a bit small for us to travel in so we now have a 2019 Ford Flex AWD it still does not do as well on gas as the Grand Marquis but seems a bit faster in acceleration. The 3.5 V-6 also has enough torque so it does not down shift often on hills .

[tomme boy]

If their is metaal in the trany pan, changing the fluid will not work. The metal is what is holding it together.

Ever heard of someone changing their trany fluid and the trany goes out a mointh later? This is why.

[elmacgyver0]

The plug wires break down with time and heat, seems no one changes them anymore.
Look at them in the dark with the engine running you may be surprised at what you see.

[6bg6ga]

Instead of buying new coil packs, just buy the rebuild kits. The rebuild kits only cost about $5-6 each. that replaces the rubber boot and the wire spring that makes the connection to the spark plug. Easy job to do and not that cost prohibitive.

Very seldom is this the answer to the problem. The coil windings go open for a split second and then close again. The windings heat and cool open and close and this causes the miss.

[6bg6ga]

If you have to replace the converter the ONLY proper way to change the fluid is to POWER FLUSH. You hook it up to the machine and it basically pumps the old out and the new in. Depending on the machine they can also filter the fluid. The last power flush I had done cost $100 and added another 100K+ miles to the life of the tranny. My boss was one of those that listened to the old wives tale that if you change the tranny fluid the tranny will die soon after. Its kind of funny because about a month after I had the tranny power flushed the bosses Chevy suburban developed a tranny problem and he took it to the chevy garage and they did a power flush on his tranny but that was ok because it was his company vehicle.

[rdwarrior]

Very seldom is this the answer to the problem. The coil windings go open for a split second and then close again. The windings heat and cool open and close and this causes the miss.

Well it was the answer to my problem because it cured my problems that appeared to be identical to the OP situation.

[6bg6ga]

The OPs problem based on the symptoms is coil break down not a boot/moisture problem from what I have read. Based on my over 45 years of playing with autos I would say that moisture problems not always but for the most part will slowly change in the intensity of the miss with run time.

[Battis]

Here's an update. My mechanic replaced #2 and #3 coils (both showed on the scan). He replaced all the plugs and wires (no charge - they were done a year ago so he put it through on a warranty). He checked all the other coils with a known good coil (I had #4 done last year). The car runs much better, but...it still bucks at 40 MPH unless you shut the OD off to get past that speed. So, he ordered a torque converter that will be in Monday. There are no misfires now showing up on any scan (even in Mode 6). Hopefully the torque converter will be the answer.
So far, I'm into the repairs for $300 (including the converter). That's not bad, especially if it's fixed.

[6bg6ga]

I remember mentioning there were two coil packs that always need replaced on the Ford. With my experience with the Ford torque converters I guessed that one also. When you engage the OD at around 60-70 mph climb a hill and you will get a slight bucking activity. Quick turn off the OD and the activity will cease. The hill should be enough to stress the engine to promote a miss. Try out what I mentioned and I'm sure it will follow the same symptoms with the perceived miss that will clear when the OD is turned off.

[Moleman-]

FWIW, we had the same symptom happen in our crown vic. Mechanic replaced the trans filter and the problem went away.

[brass410]

this is what usually happens in these scenarios, you have an issue which is comprised of several issues all coming together at one time, and being judiscious and frugal we always (mechanics and other mechanicaly inclined persons) try to fix in the most expedient manner ( reads most obvious and frugal) then we move on to the last of the symptoms. IE swmbo says kitchen light doesn't work, my reply did you turn the switch? As my senses slowly return from the death glare I suggest maybe I'll ck the light bulb then then fuses, after all it's a pretty big expense to just go out and have a new power line and service put in only to find out that the power transmission line has been compromised by a storm. I believe most suggestions here are based on personal experience and we all like to try and save the worst for last, you may very well have to do some transmission work but at least you haven't just tossed parts randomly at it without consideration. Remember cars, firearms, and spouses are all the same, everyone is different!!!!!

[kens]

I'm still betting it is coil packs, and or, oil soaked plug wires/boots.
I'm betting it is not a torq converter problem.

[dkf]

It is not uncommon for misfires to feel like a transmission problem.

How many miles on the spark plugs?

PO303 is a cylinder #3 misfire. The COP can be ruled out by switching the number 3 COP with a known COP from another cylinder and seeing if the misfire returns.

I don't leave a set of plugs in a modular engine more than 50k miles. Yes they can go 100k but in my experience once they get past 50k miles the issues with misfires, detonation and lack of efficiency start to become more prevalent. The Motorcraft COPs are pretty good and can last a very long time, people usually think the COP is bad when usually it is something else causing the misfire. Half a million miles and over two decades with modulars in my driveway and I have yet to have one need a new coil. The plug, boot/spring or fuel is far more commonly the issue than the coil itself. The boots can crack over time, allow moisture or other crud in and cause a misfire. It usually takes a pretty bad misfire to even throw a code, especially on the older modular equipped vehicles running a dumbed down OBDII system like the larger trucks. Start out with the easy stuff first, plugs, boots/spring and fuel. The fact that you finally got a misfire code leans even further away from the possibility of a trans issue.

[megasupermagnum]

Here's an update. My mechanic replaced #2 and #3 coils (both showed on the scan). He replaced all the plugs and wires (no charge - they were done a year ago so he put it through on a warranty). He checked all the other coils with a known good coil (I had #4 done last year). The car runs much better, but...it still bucks at 40 MPH unless you shut the OD off to get past that speed. So, he ordered a torque converter that will be in Monday. There are no misfires now showing up on any scan (even in Mode 6). Hopefully the torque converter will be the answer.
So far, I'm into the repairs for $300 (including the converter). That's not bad, especially if it's fixed.

If any misfires showed up at all, I would not be looking at a torque converter just yet. Ignition is not the only way to get a misfire, especially a random misfire, which often goes away if you downshift. This can also be caused by a lean condition, something like an air leak. The torque converter might be cheap, but removing a transmission is not. It's worth asking a mechanic to have a good look over the engine with some carb spray for air leaks. Even the EGR system can fail and not throw a code, yet cause random misfires.

[dkf]

An air leak or fuel pressure issue usually will throw more than just a misfire code in one cylinder.

[6bg6ga]

Here's an update. My mechanic replaced #2 and #3 coils (both showed on the scan). He replaced all the plugs and wires (no charge - they were done a year ago so he put it through on a warranty). He checked all the other coils with a known good coil (I had #4 done last year). The car runs much better, but...it still bucks at 40 MPH unless you shut the OD off to get past that speed. So, he ordered a torque converter that will be in Monday. There are no misfires now showing up on any scan (even in Mode 6). Hopefully the torque converter will be the answer.
So far, I'm into the repairs for $300 (including the converter). That's not bad, especially if it's fixed.

Here I thought the problem was well on its way of being solved.

[Battis]

So did I. They changed two coils, all the plugs, and the solenoid for the torque converter (not the converter as I posted before) and flushed the transmission. It ran well for a day - no bucking- then it stalled. The code was from the accelerator actuator, which they'll replace tomorrow. I'm still not into the repair for a lot of money. The transmission place said it'd be about $1200 for the torque converter if it comes to that.

[megasupermagnum]

So did I. They changed two coils, all the plugs, and the solenoid for the torque converter (not the converter as I posted before) and flushed the transmission. It ran well for a day - no bucking- then it stalled. The code was from the accelerator actuator, which they'll replace tomorrow. I'm still not into the repair for a lot of money. The transmission place said it'd be about $1200 for the torque converter if it comes to that.

I'm not familiar with Lincoln, is that like a throttle body, or was it the throttle position sensor? Either way, that would certainly cause a random misfire.

[Hossfly]

My 2012 F-150 developed a buck or hiccup after really warmed up pulling load of hay with 30’ gooseneck. Took to Ford dealership several times for computer testing. After a couple times not finding anything definite except 2 plug coils, took truck in with a full gas tank, just left it with them and said keep it till its fixed. 2 days later they found the high pressure fuel pump wasn’t up to specified pressure. They changed pump and been running good for past 2 years. Happy camper about $700.00 worth. Eco boost engine 6 cyl.

[Battis]

I'm pretty sure it's the throttle position sensor.

[Battis]

2 bad coils, solenoid for torque converter, and the throttle body (not the sensor - there is a difference, right?) and it runs great.

[Hossfly]

Happy they found it.