As some of you remember, I got a new SCT SF3/X3 tuner a few weeks ago and I have been having nothing but fun with my car until a few days ago. Decided to put the stock tune back on my car before dropping it off to get it aligned. After it was finished downloading, I go to start my car and it runs really rough for about 5-10 seconds and then dies. Or I could start it, press the accelerator and the car dies. It won't stay running on the stock tune anymore but it runs like a charm on one of the three preloaded tunes. I emailed Bama, explained to them whats going on and they are working with me to get this figured out but can't seem to pinpoint anything either right now. Has anybody else ran into this problem or does anyone else think they have an idea on whats going on with my car? Thanks in advance.

 

You might try disconnecting the battery for 5-7 minutes after loading the stock tune--this will clear the Keep Alive Memory (KAM) and for the PCM to relearn things like idle air and short term fuel trims.

Flashing a tune is often stated to clear the KAM, though I have never had verification of this and there is no mention of this in any of Ford's documents that I have seen...

 

Doing that actually crossed my mind but I have yet to do it since I am in georgia right now without my car. I will try that when I get home tomorrow. This might be a stupid thought but will a stock tune run different on 93 octane gas? The manual suggests running 87 octane in my car but since I have a 93 octane tune loaded onto my car will that make the car run wierd when I switch it back to stock?

 

Running 93 with the stock tune will not affect anything, other than the weight of your wallet, once you have reset the KAM...

 

Alright, so I had my car in the garage, downloaded the stock tune back onto the car and disconnected the battery for 10mins so it could clear the KAM as cliffy told me to do. Re-connected the battery, started the car and the same thing is happening. Car is shaking and then stalls after about 5-10 seconds. Also getting a strong odor of gas coming from the exhaust too, so bad that my whole garage smelled like somebody spilled gas. So I put one of the tunes back on the car and it runs fine and no gas smell. No idea whats going on.

 

sounds like a vacuum leak. look for loose vacuum hoses, the one on the back side of the throttle body was notorious for popping off my car (before i was boosted) so i had to get a hose clamp and clamp it down..

also try and re-upload the tune you had working prior to going to attempting to reload the stock tune, if you havent already. if it works with those tunes thats really odd, and not a vacuum leak...

edit: just saw that it runs good with the other tunes, so what reason would you need to swap back to the stock tune?

 

The original reason for swapping it back to stock was because I dropped it off to have it worked on and didn't want them messing with the car while I wasn't there. Call me paranoid.

 

cant you set the rev limit on a modified tune? then just set it to something like 3000 rpms lol. valet mode.

 

Yeah, I can set the rev limit on my tuner. I don't know much about this tuner so I don't feel like going into it a messing with things until I learn a little more. Knowing my luck, I would probably mess something up and won't be able to fix it.

 

lolz @ 3k gov'na.