1G Backfires after fmic

[pauleyman]

Was this a backfire or simply fuel cut? Is the car otherwise stock?

 

[1990TSIAWDTALON]

I have had a TB act sticky before after a rebuild and you just loosen up the nut under the TPS a bit and it will loosen it up. Just an observation from what I have had happen. ALSO, if the throttle plate reinstalled incorrectly it will hang on you.

 

[curt-s]

You should fill out a full vehicle profile so that way we know what you have, modified or not.
Have you even checked your fuel trims for signs of fueling/oxygen sensor issues?
It might have happened while you were putting on the FMIC, but it could have been completely coincidental.
Or, you could have hit something and accidentally damaged it, cut a wire, or who knows what..

Because, as you said, you did a proper boost leak test and have ruled out the possibility of any leaks.

 

[dsmBear]

Added a build profile like you recommended, backfires like it's an srt4 but not as bad or loud

 

[mercaholik]

Back fires out the exhaust, if it backfired up the intake it would be quite noticeable. Usually that backfire between shifts is from a richer a/f ratio. Do you have a way to check your a/f ratio, w/b perhaps? It is possible the ecu's injector drivers were damaged, but most likely it's not.

 

[dsmBear]

Update: re preformed
Boost leak test found a little leak at a ic coupler, fixed and is a bit better but still leaked. Did blt again and no leaks in fact the part of my tester where the valve is popped off from the pressure. So the intake system is good? Must be leaking at the turbo deals ?