Hesitation/misfire under boost

[oneSICsvt]

So i posted a thread a few days back about my car bein in the shop, TOB was replaced now the car runs like shit. I was told maybe a pinched wire or unplugged O2 sensor or something along those lines.

I didnt drop the tranny but i reached behind the motor and checked the connectors i could reach and they were fine. I changed my spark plugs, I changed my air filter, I cleaned my MAF sensor, and its still running bad. But after further tests i found that it only does it under boost

When i accelerate normally without hitting boost the car runs smooth as pie, but once i hit boost the car shutters or shakes a little bit and it feels like theres absolutely no power. On my boost guage i am getting full boost, but it feels like there is no power. The odd part is if this is a misfire its not throwing a code. There is no check engine light on but under boost it hesitates. Does anyone know what the problem could be or has anyone experienced this.

Thank you in advance for your help. I need to get my baby back on the road

 

[04SolidSnake]

What are you plugs gapped at? How much do you trust your shop not to beat your car? Could be a blown FRPS, which is causing too much fuel to be dumped into the cylinders preventing it from igniting.

Do you have a tune in the car? Sometimes tuners will disable the CEL altogether..

Does the oil smell like gas? That'll be a good indication of too much fuel being delivered. If that is the case, you can pull your plugs out and check to see if one cylinder is more fouled than the others, and you can narrow it down. Could be as simple as the coil not making good contact with the plug..

Good luck!

 

[oneSICsvt]

What are you plugs gapped at? How much do you trust your shop not to beat your car? Could be a blown FRPS, which is causing too much fuel to be dumped into the cylinders preventing it from igniting.

Do you have a tune in the car? Sometimes tuners will disable the CEL altogether..

Does the oil smell like gas? That'll be a good indication of too much fuel being delivered. If that is the case, you can pull your plugs out and check to see if one cylinder is more fouled than the others, and you can narrow it down. Could be as simple as the coil not making good contact with the plug..

Good luck!

I gapped them at the factory gap that i looked at on alldata. And i know for a fact they didnt beat on my car because its a dealership where i work and where i bought the car. I do not have a tune in the car its bone stock performance wise. And i have heard about the FRPS before, how can i tell if its bad. And where exactly is it located. Also how much is it to buy one, maybe i can just try that if theyre cheap just to see if thats the problem.

thanks for the help

 

[04SolidSnake]

I gapped them at the factory gap that i looked at on alldata. And i know for a fact they didnt beat on my car because its a dealership where i work and where i bought the car. I do not have a tune in the car its bone stock performance wise. And i have heard about the FRPS before, how can i tell if its bad. And where exactly is it located. Also how much is it to buy one, maybe i can just try that if theyre cheap just to see if thats the problem.

thanks for the help

Take a sniff of the oil from the dipstick.. If it smells like fuel I would think that would be it. On a stock car though, it sounds more like a loose connection or a vacuum leak somewhere..