reboot of trucks CPU to 89 Octane

[Steve Kaufman]

Wasn't sure what to put this under....Years ago I bought a tuner for my truck and upgrade to 93 Octane gas. When I tried putting it back to 89 it made me get to like 5000-6000 rpms before it would change gears...SO i put it back to 93 and it fixed the problem.



With the price of gas as it is right now, I really want to get rid of the 93 octane tune BUT I lost the tuner. My dealership said that their system wouldn't reset the cpu, and there is no way they can guarentee that it will fix the problem if they were able to completely reset it to stock.



Can someone help me get back to 89 Octane without the RPM issue happening?

 

[Todd Z]

Put it back to stock and drive it around the block....



Then disconnect the NEG bat cable for 1/2 hour and go from there...



Works most of the time..



ALSO I got a STOCK tune from Torrie that just did the transmission shifting but left the motor stock.... Thats a great tune...



Todd Z

 

[Thomas Rogers]

Steven,



Aren't tunes great? (rolls eyes).



When you put the original program back how long did you run the truck before taking it back to the 93 octane optimized tune? Hours? Days? A week or more?



Some here have said that after a tune the truck has to be run for a while to re-learn things. I don't know if that is true.



Also, there should be volatile and non-volatile settings within the truck computer. The tune (program) itself is in non-volatile area meaning that even if your truck has a dead or disconnected battery that program won't be lost. That's a good thing. Other settings are what the truck learns from your driving behavior and optimizes performance based on that, and the fuel you use, etc. Those are in a volatile area, meaning if power is lost for a period of time the computer forgets that information.



So, I guess another thing to ask is whether or not you re-tuned it back to original, then disconnected the battery for a period of time (not sure how long).



Others more familar with the fun of tuning (something I avoid because I feel its more trouble in the long run than its worth) will likely provide more expert advice and correct me where I am wrong.



Good luck.



UPDATE: I see Todd beat me. Yes, I suspect the disconnect of the battery may be the main, missing link.



TJR

 

[Les]

BUT I lost the tuner.

 

[Thomas Rogers]

Even with a lost tuner, the disconnect the battery advice after a reset to original by the "stealer" is the take-away advice here that may help the RPM re-learn issue.



TJR

 

[EddieS'04]

I would talk to another dealer. Or it may be cheaper to trade your ECU for a new one.