gunnerm109a6

I just bought an 06 scab with the 5.4. The previous owner made some mods and apparently tinkered with the programing. The truck is not running as well as it should and the mpg is on the low end. Would this process, in effect, reboot the computer back to factory settings?

Thanks for the great thread!

CaptainT16

I'm going to give this a shot. I did the entire timing process this past weekend and tried pulling out of the garage and didn't move 5 feet and it stalled on me. Tried starting it again and fired right up and sounded great. Reversed again and same thing. As long as I'm driving normal speeds, the engine sounds great, almost like a brand new truck. Going to clean the mass airflow valve and throttle body as well.

Now, I know doing this we had to disconnect the A/C condensor line while pulling the valve cover. Can I just turn the defrost on instead of the A/C since it won't run since the disconnect? Can't wait to give it a shot, but would be curious to see if I have to run the A/C or if the defrost on high would work okay.

Thanks again!

LEN671

Interesting. I will definitely try this ASAP!!

Donnie Kirby

Does this clear/reset the wrench light? I have read that only the ford dealership can clear that particular light. Is that correct?

chayes627

Is the relearn process something that should be done after flashing a new custom tune?

Dukus832

heck yea great thread, i just installed new headlights on my truck and a new radio and the dang thing runs great till it warm up and then every time i stop it goes dead with me.... hope this works for me because the only thing wrong with my truck was a cam phaser positioning sensor and i replaced it at the same time now my check engine light is on again....ill follow up and let everyone know my results.

brosephyoung

I changed my IAC valve and the idle was all over the place. I had the battery disconnected when i was putting the new part in to let the computer board drain. After i was all done i drove my truck, going 40 mph then coming to a stop quickly. My truck would idle really low and sputter then it would eventually balance out. I did some normal driving in the city as well with mixed results, sometimes it would idle perfect when coming to a stop and other times it would sputter. I noticed that if i was going fast and came to a sudden stop it would sputter then even itself out after 5-10 sec. My thinking was that if i drove the truck a bunch of different ways that it would relearn everything, that didn't work out the way i planned. I came across these instructions and gave them a shot and had much better results than my way of doing it. During each step the truck idled high/low and when it finally leveled out i waited 2 min then continued on to the next step, i did this for all steps. Also i added a step and put it in reverse with foot on brake until it leveled out and waited 2 min. I then drove around, maybe 15-20 miles going uphill, downhill, flat, stop signs etc not trying to do anything i wouldn't normally do when driving and the truck started running like normal again. During my 20 min of city driving i only had a few instances of high/low idle but majority of the time it was perfect. I do believe this process worked and now all i have to do is maybe drive some more to let the truck fully relearn all possible scenarios. Thanks for the info.

gmctech

I'm blown away by the difference this has made to my truck. 2004 new style 5.4L 4wd. My cam phasers rattled so badly people thought it was going to puke it's guts out at idle.... then I did this and I'm floored.... Engine is quiet now, shifts are smooth as silk, idle is smooth. Took a buddy for a cruise and he couldn't believe the difference it made in my aging beast.

Took my buddies 2011 Taurus SHO and did that too as it was a bitch to start after a hot soak and voila! Problem resolved! He took it today on a 500 km journey and called to tell me it's now back to its incredible self like it was the day he picked it up from the stealership.

I was a Red Seal tech for GM for 14 years and an ECM/PCM reset would never make such differences without an actual reprogramming.

My F150 used to require WOT to start after a 20 minute hot soak, now just bumping the key has the old 3V purring!

Interceptor2

The battery relearn process decribed at
https://www.f150forum.com/f72/battery-relearn-process-133736/
worked beautifully on my Procharged F150 2000

I have air/fuel (AF) ratio gauge and thought that the following data might be helpful.

I changed the 16 year old stock fuel pump, and after that change the idle in the truck was rough at 500 rpm.

I followed the battery relearn procedure and after starting the engine the AF gauge no longer cycled in the stoichiometric range, rather the gauge was fixed at near RICH. The AF gauge stayed steady throughout the procedure, but not pinned at RICH. At the seven(7) mile mark I was on the highway, the engine tone changed and AF gauge began showing normal cycling in the stoichiometric range. The idle is fine now at 600-650 rpm and still runs like the day I bought it new.

petef-150

Did the relearn on my 1999 this evening. left the battery unhooked 3 hours, then did all the steps. But he Ebrake part, my Ebrake cables are gone. Will have new ones on it soon. If this did not help this evening, it may be something with the ebrake that stopped it.
Drove 24 miles, to the river and sat there a few minutes. Then back home doing anywhere from 35 MPH to 70 MPH.
Pete