HA!! The 5.4 F-250 just thought it could outsmart me.

The other day, I did the dreaded spark plug and ign. coil change on the 2006 F-250.
All in all, it went well, and I declared a victory.

Upon driving it more, I found that when I pushed in the clutch, and came to a stop from 50mph or more,
it'd idle down to 250-300 rpm, not quite stall, then 'think about it for a bit', and come back up to 750.

I figured: Hmmmm,,,,,, this will not do.

So I got to researching some more about why it did that.
I found all sorts of things it could be, and needed to be changed. Various sensors, the throttle body,
all sorts of things that I knew hadn't just died because I changed the plugs & coils.
-------And some of them even cost less than $200.

I finally found an old car forum post about if you change certain things--- it has to 're-learn' how to idle.
Oddest thing I ever heard. But I had unplugged the big wiring bundles to be able to reach in behind them.
According to the truck--- that counts as changing certain things.

I found out you have to 'drain' the forever memory in the computer by taking off the neg. battery cable,
then touch it over to the (+) post for a minute.

After that, you have to start it, and let it idle for 20 minutes, then drive for at least 30 miles so it can re-learn
how to idle and adjust itself to your driving habits. I've read the shop manual cover to cover, and never saw that.

After working on carburetors and breaker points ignition, with a few GM HEI ones thrown in,
that was the oddest thing I ever heard of.

But I did it like it said, and that fixed it.
Now I can look out the windshield instead of staying focused on the tachometer.

That right rear plug is a pain to change or at least it was on my son’s F-150.
His engine blew 4 spark plugs out of the heads over a years time and I had to put those threaded inserts in.
I finally bought a low mileage engine and just replaced the whole thing.

My new to me Ford Escape I had the dealer do a reset before I brought it home. Same thing, it learns your driving habits and the person who had it before me drove like an old lady(Okay I am 60, I can say this LOL) from the readouts I saw. Never built much boost, never took it above 3k RPM... I am a leadfoot, I exercise my engines!

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Originally Posted by Rightbrained

That right rear plug is a pain to change or at least it was on my son’s F-150.
.

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You'd think the engine compartment was the same on all the full size trucks, but it ain't.
Watching the plug removal thing, (mine is the generation after the one where the plugs blew out)
but I only had to unplug the computer thing and move the wires out of the way.
All the videos I saw that were with the same task on a F-150, they had to pull the computer out.

I had to take out the windshield washer tank, but they didn't on the F-150s.

How many miles? Those IAC valves like to gum up. Had to replace the TB on my brother me 2005 F-150 about 2 years ago. Found one at Napa and it’s been running good since.

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Originally Posted by Winger Ed.

You'd think the engine compartment was the same on all the full size trucks, but it ain't.
Watching the plug removal thing, (mine is the generation after the one where the plugs blew out)
but I only had to unplug the computer thing and move the wires out of the way.
All the videos I saw that were with the same task on a F-150, they had to pull the computer out.

I had to take out the windshield washer tank, but they didn't on the F-150s.

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I don’t know much about Ford’s so I didn’t know the engine compartments were different.
Glad you got her sorted out though !

There’s a vacuum line that plugs into the back of the passenger side intake manifold that likes to pop off and make my 04’ F150 5.4l stall out at idle. It’s a PITA to plug it back in as well.

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Originally Posted by osteodoc08

How many miles? Those IAC valves like to gum up. Had to replace the TB on my brother me 2005 F-150 about 2 years ago. Found one at Napa and it’s been running good since.

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I bought it new in Aug. of '06, and I just turned 59,000 original, very gentle miles on it.
I change the oil & clean the K&N air filter every 3,000. And did the transmission & rear axle a few years ago at 40-odd thousand.
The radiator gets flushed every 5 years, and fresh tires at about 25,000. They get hard and wear out well before they should.
The worst its been treated was dragging about a 8,000 pound tandem trailer for 80 miles.

Some years, just going back & forth to work, the annual state inspection stickers were only 2,000 miles apart.
One year it was 700 miles between them.

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Originally Posted by MaryB

My new to me Ford Escape I had the dealer do a reset before I brought it home. Same thing, it learns your driving habits and the person who had it before me drove like an old lady(Okay I am 60, I can say this LOL) from the readouts I saw. Never built much boost, never took it above 3k RPM... I am a leadfoot, I exercise my engines!

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very true mary ive done it in my challenger. You pull the #2 fuse which kills power to the computer to reset it. Seems that if you drive in 60mph down the road and drive it sanely the computer learns that and adjusts timing and fuel curves and you actually loose hp. They say if you dont drive hard to pull the fuse about once a month to reset it. Not much worry with me driving though!!! you an actually do the same thing with the diablo programmer i have for the car sitting on the seat.

My brake light is on as well. I replaced the sensor ...didn’t fix it. I took apart my dash to find out it’s a loose connection. I will have to get some electrical grease to see if it helps. I’ve cleaned the connection and even wedged something in the dash to hold it tight. The light still goes off and on. If I hold the electrical plug down with my finger, or hit the dash, the light goes off. No where to attach a zip tie to hold it in place. Maybe I’ll put a lead ignot on top of it and wedge it between the dash and connection. Lol. If not I’m just going to unplug the sensor and call it a day.

Yes, vehicles have adaptive learning strategies built into the computers. They compensate for wear on the vehicle, reduce emissions, give the driver a more consistent feel to how the vehicle operates and help fuel mileage. The electronic transmissions measure how long it takes to shift, then compensate for slippage. It is possible to ruin a new transmission because the adapts were not reset when it was installed. On some of the newer vehicles, the adapts need to be reset when installing a new battery. Cool stuff, but it makes it hard for the average person to properly repair their vehicle.

Dave W, hit the nail on the head. Most automotive on-board computers employ adaptive learning. Just about all of them will need to re-learn if you disconnect the battery. Some setups are worse than others. Most will "learn" again in a few minutes but some take considerably longer.

As for disconnecting the negative cable and touching it to the positive terminal.......I'm a little skeptical about that process doing anything.

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Originally Posted by Winger Ed.

.........

Some years, just going back & forth to work, the annual state inspection stickers were only 2,000 miles apart.
One year it was 700 miles between them.

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True Story: Years ago, Virginia required vehicle inspections every six months. There was an elderly lady that owned a beautiful 1966 Bel Air. She lived about 2 miles from the garage. On one occasion she presented the car for inspection and it had 4 more miles on the odometer compared to the prior inspection. She had the car inspected, had driven the car home, parked it and six months later drove it back to the same garage !

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Originally Posted by Petrol & Powder

.....I'm a little skeptical about that process doing anything.

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It didn't make sense to me either.
But I've changed the battery a couple times, and it didn't effect anything.
I was reading about the Ford having a 'forever memory', and to wipe it out & drain the capacitors that made it work,
that's what ya had to do.,

Yeah........
It may be an example of a faulty cause & effect belief.

A guy is walking down the street singing a song and twirling his left finger in the air. Another person asks him what he is doing and he replies, "I'm keeping elephants away". The other person says, "that doesn't keep elephants away" and the first guy responds, "Do you see any elephants"?

I'm sure someone disconnected the negative cable from the battery, touched it to the positive terminal and the computer reset.
HOWEVER, that doesn't mean the computer wouldn't reset without following that procedure. It is entirely possible that you could achieve the same result by disconnecting the negative terminal, waiting a moment and reattaching it.

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Originally Posted by Petrol & Powder

It is entirely possible that you could achieve the same result by disconnecting the negative terminal, waiting a moment and reattaching it.

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Yeah, that makes sense to me.
But I figure changing the battery would have gotten me to the same place, which I've done a couple times with no effect.
But then,,,, I don't totally understand its 'forever memory' thing either.

Anyway--- I'm glad its done, and the truck is back on the 'ready' line.
I sure am more comfortable working and tinkering on our boat.
It has a late 60's GM 4 cylinder with points, and a 2BBL carb.
I understand it much better than all this modern age wizardry, that I don't even like opening the hood and looking at.

I'm with you.
Give me old technology any day of the week !

The 5.4 Triton in my F150 has quite the interesting rear spark plugs locations. First warning they might be a little hard to get to was when I learned Ford has a special tool to take out the busted ones.

I've heard of the "relearn the idle and driving" thing but not touching the opposite post just take them off the battery for several minutes the reattach.

I had a Ranger a number of years ago. I decided one spring to change the plugs and broke one off. Called the local Ford place 40miles away and they came and got it. Next spring decided I just had to have platinum titanium split tail super plugs so went to remove the others and broke off the same one. Called Ford and they came and got it again. Next spring I didn't want to go that route again so left it.
Come May or so I get a call.
"Hey, jonp it's Bob from Ford how you doing"?
" Good Bob"
" Haven't heard from you, you going to need the flatbed again"?
:rolleyes: I could hear the shop laughing in the background. Smart aleck

Quote:

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Originally Posted by Winger Ed.

Yeah, that makes sense to me.
But I figure changing the battery would have gotten me to the same place, which I've done a couple times with no effect.
But then,,,, I don't totally understand its 'forever memory' thing either.

Anyway--- I'm glad its done, and the truck is back on the 'ready' line.
I sure am more comfortable working and tinkering on our boat.
It has a late 60's GM 4 cylinder with points, and a 2BBL carb.
I understand it much better than all this modern age wizardry, that I don't even like opening the hood and looking at.

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if you factored in the parts and labor that 2006 truck would have needed on top of what you spent if it was an old school points and carbed motor you would change your tune about the new stuff. I chuckle when i hear storys of guys who have sparkplugs seized into a motor (even iron heads) because they didnt change them in a 100k. You sure didnt have to worry about that in the 60s you had to buy new plugs and points about as often as you changed oil which by the way needs to be changed about twice as often as the new trucks need. Used to be you took your vechile to the fill-in station and some grease covered guy who didnt even get past the 7th grade started slapping parts on it till he found the right one. Today your computer tells you something is going bad before i many cases it totaly fails and will give a code that a GOOD mechanic can look up and in about 5 minutes with a multi meter tell you exacty what part needs attention.


Even if you are leary of wrench on one you can buy a code reader and pretty much narrow it down, go to your mechanic with that info and chances are just the fact he knows you know will keep you from being taken for a ride. I worked for one of those jag offs for about 2 months in chicago. He would do wrecker work. Cold winter cars all over wouldnt start. He would tell just about all of them that they ran there battery down and caused the starter to go bad. 10 minutes with a can of brake cleaner on the starter and a new battery when in must cases the guy just left lights on and nothing was wrong. Im sure this kind of crap goes on in every city in the country. Now at least if i get a code i can come in with enough knowlege not to get ripped off by someone that just throws parts at problems. Many times a code only has one problem that can cause it and about anyone can unplug a sensor and plug a new one in. Nothing to be scared about. I chuckled at the dealership one day. They had the hood of a new caddy open and the whole thing was under a cover. Dealer chuckled and said cadilac did that so youd be afraid to work on it and probably wouldnt even trust your local mechanic. He said many actually believe its a seal that you cant break. Most people today wont even change there own oil and woudnt know a grease gun from an ar15. Get a service manual and a code reader and jump right in there. Youll find that trouble shooting a new one is much easier then an old one. Just look at how many moving parts are in a 4 barrel carb that can cause your car to run bad. Points??? They dont even have a distrubutor. Let alone something with moving parts that can wear. Just the fact that cars last 3 times longer then they did in the 60s tells me which one i prefer. Im a big fan of that modern age wizard!!

I have an engineer friend who is prone to claim that automotive technology hasn't advanced much in 50 years. My Dad operated a service station for the last half of the 20th century. Today, a spark plug cleaner that uses sand to blast carbon off plugs is an antique. Plugs last 100K rather than 10 or 20K. He had a cellar filled with rusted mufflers, exhaust pipes and tail pipes. I know because I was the one who carried them up to put outside for the scrap guy. Radial tires were a rarity encountered on the occasional French car. There were a dozen or more grease zerks on the steering and front suspension and the parts still wore out. Detergent oil was new when he went into business and an old engine with 50K that switched from non-detergent to detergent oil was at risk of becoming an oil burner because the new oil cleaned it up. Perhaps manufacturing doesn't take advantage of all the latest advances in technology, but it gets there with the good ones. Some are tried and abandoned. Remember the Wankle engine?