Misfire when car warms up

[slayer650]

I have a 91 Talon TSI AWD. The car runs great when the car is cold, but as soon as it starts to get to normal operating temperature it starts missing, it gets worse the warmer it is. after it gets to normal temperature it won't rev past about 3000rpms without missing. If i keep the throttle held down when it starts missing it will shut down until i let off the throttle.

The ecu has just been rebuilt, it has new plugs and plugwires-both are ngk, i've changed maf's, and i've done a boost leak test. i keep getting a check engine light for my tps, but doesn't stay on all the time. The car is stock except for exhaust.

anyone have any ideas?

 

[sergiosdsm]

Since the check engine light is coming up with a TPS code I think the wisest thing would be to check that first. heres how you test to see if its good and to adjust it.

http://www.plymouthlaser.com/tps.htm


hope this helps

 

[ivanr4g63]

Even if the TPS is bad, it should not cause that bad of a missfire when warmed up, or at least it didn't in mine even when I had it unplugged one time for other issues I once had.

I would've suggest looking into your fuel pressure, but you said it runs fine when cold, though it may run rich when cold since the ECU compensates for the warm-up mode, and leans out as the car reaches normal temp, with this in mind is your timing way too advanced maybe? do you have a timing gun handy, try that and see what it does

also let me ask you: Did the car did this before you changed plugs and wires? did you gap to the right setting? are you using stock bpr6es?