Removed chip-now no idle!

[spartanpride]

I purchased my Mustang with the mods in my sig (well most of them) already done including the chip. I thought maybe the chip might be programmed for wrong MAF and TB than I have and it might be hindering rather than helping so I took it out just to see. BIG difference believe it or not! Better than before. However now I have no idle! Just sitting in neutral it just dies. Rolling down the road at like 30 with the clutch in, it also dies! I unplugged my battery thinking my computer might "relearn" or something without it. Still no idle!
HELP ME OUT HERE FELLAS PLEASE
And Thank you!

 

[HISSIN50]

Do you know what is on the chip or what parameters were changed?

You might have issues trying to run that combo without the chip (assuming the MAF and EEC are on the same page for the 24's in the first place). You'd not be the first to have issues with the idle and that cam.

 

[spartanpride]

Unfortunately I dont know what the chip has programmed on it Any fixes without putting the chip back in? Perhaps do you think it's a MAF calibrated for my 24's that will fix my problem or what?

 

[HISSIN50]

What MAF is in the car now? The stock MAF was also used on Cobras (with 24's), so it's adequate and might still be in the car (the chip might have been what told the EEC about the 24 pound injectors if you don't have a Cobra EEC in the car).

So if you have a GT EEC and stock F2XX Maf, the EEC won't know about the 24's (it will assume 19's). And the cam might still be an issue.

The place to start is pulling codes.

I would see about having the chip read (if you want to know what's on it) and then reinstalling it so the car at least idles. Anything else is not likely to be correct for the components in the vehicle. For information's sake, here's the idle setting procedure:

Ford Mustang Base Idle Reset

 

[jrichker]

See the "Surging Idle Checklist for help with all your idle/stall problems.

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.

 

[vristang]

I purchased my Mustang with the mods in my sig (well most of them) already done including the chip. I thought maybe the chip might be programmed for wrong MAF and TB than I have and it might be hindering rather than helping so I took it out just to see. BIG difference believe it or not! Better than before. However now I have no idle! Just sitting in neutral it just dies. Rolling down the road at like 30 with the clutch in, it also dies! I unplugged my battery thinking my computer might "relearn" or something without it. Still no idle!
HELP ME OUT HERE FELLAS PLEASE
And Thank you!

I don't get it...
So it idled and ran pretty well with the chip, but you decided that the chip *might* be programmed for the wrong MAF... so you pulled the chip?

Put the chip back in... problem solved.


Getting more serious...

Why did you pull the chip?
What problem were you hoping to resolve?

Post the following...
Catch code of the ecu:
Injector size:
Part numbers on MAF:
Aftermarket MAF?:
Description/brand of chip:

Pics may help as well.
Gotta know what you have before you can decide what to change.

Pulling codes would be nice too... both with and with out the chip...

 

[Mustang5L5]

Is this a off-the-shelf chip??? OR a custom burned chip?

 

[spartanpride]

"custom tuned" SCT. In the car when I bought it, don't know what it has programmed on it however. 24lb injectors stock TBand MAF. I pulled the chip to see if perhaps it was hindering more than helping, my hunch was right it was hindering performance. I reset my idle like HISSIN50's link said and idles great and runs great! Thanks all!

 

[2000xp8]

"custom tuned" SCT. In the car when I bought it, don't know what it has programmed on it however. 24lb injectors stock TBand MAF. I pulled the chip to see if perhaps it was hindering more than helping, my hunch was right it was hindering performance. I reset my idle like HISSIN50's link said and idles great and runs great! Thanks all!

The chip was probably done in the first place because whoever had or worked on the car didn't know how to get it to idle properly.
Just another case of using a chip to bandaid a mechanical problem.
I've said it 1000 times, it's almost impossible to beat the stock computer for power and driveability.

 

[Mustang5L5]

The chip may also be there for the injectors, and a general tune.

The OP did state the car has 24# injectors, and a stock MAF. Kinda makes sense there. I bet if he were to swap to 19's, it would probably run well.

The mods don't really justify 24#ers yet