Stumble, spit pop!


Active Member
Ok, I am ready for someone that knows more than me about these damn cars...I have been fighting an issue and I can't figure it out. As soon as my car comes up on boost it starts stumbling and acts like it is dropping a couple of cylinders. Fuel pressure is strong and steady, I have a Scanmaster but I need someone that is willing to come out here and drink a few beers and he me sort this out. Anyone in the Houston area (I am south in Angleton) willing to come hang out in my airconditioned shop and he me diagnose this thing?


Active Member
Start with checking the coil.
I have a spare coil, the one that is on there is brand new and it was running perfectly until I tore up my rear end. It sat for a few months while I figured out what I wanted to do with the rear end...I finally decided to replace it with a Moser M9 and installed that. As soon as I went out for a test drive it started acting up like this. It would be strange for the coil to just go bad while sitting there but anything is possible. These old school coils are certainly unreliable.


Designated LSX Hater
when this was occuring on mine I solved mine by moving the cam sensor further into the operating window of voltage. Under load it was moving itself out of the signal window and would consistantly pop sputter backfire with any sort of boost but otherwise drove fine.
If computer lost power,
I would check IAC readings, TPS readings, correct fuel pressures, plugs, plug wires. Plug wires... turn off the lights in your a/c'd garage, leave AC on and check for spark arcing off. While you are in there, check plugs for same plus inspect-wear and tear and re gap.
I'd do a new fuel filter and maybe injector cleaner. Might have gummed up.