Hey, me and my friend turboed his sunfire (60 trim). Everything was going fine but then we ran into this problem. Once the car gets into high rpm's with boost the car seems to misfire, the car pulls fine up to this point with no knock, and even when it starts there is still no knock unless you stay on it and you get small 2-3 degrees. I dont think its anything internal with the motor because it drives completly find up till 5000 or so rpm and has no idle, knock, tap or any other metalic noises. At this point im thinking fuel, the car seems to be a bit leaner then before 12.x instead of our 11.3, we had someone say the fuel pump cant keep up but its been running fine for a week or so. Also one of the brackets on the fuel rail has an issue, maybe boost could be pushing the injector outwards under boost? would that cause this? any insight would be great. the car has no problem getting into the high rpms out of boost. we are also still on the stock pump but any other opinions ideas would be greatly appreciated.
I also thought about spark blowout but we are running pretty low boost and we are gapped at .035 and for a week or so it was running fine.
Thanks!
|Forged 8.9:1 Wiseco Pistons|Forged Eagle Rods|HPTuners|60trim|Tial Wastegate|
|Precision Intercooler|2.5" Exhaust|2.5" Charge Pipes|630CC Mototron Injectors|
|Stock: Fuel Pump, Transmission, Manifold, TB, Head, Head Gasket, Ignition, Suspension...|
Same thing is happening to mine. Follow my post about it...some people have suggested a few things already and I'm sure there will be more responses.
This is the post
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450WHP Turbo Ecotec swap in the works...
what size injectors are you running?
i am using megasquirt and even with 300cc injectors 5 psi of boost is pushing the limit of the fuel injectors at stock fuel pressure.
shoot me an e-mail and we'll talk
2.2 L Ecotec, P&P Head, Stage 3 Comp Cams, Supertech 76 lb Spring kit, Supertech Oversized Valves, Wiseco 8.9:1 CR Pistons, Eagle H-Beam Rods, Home-Built Turbo Kit T3/T4 57 Trim Intercooled, 78 lb/hr Racetronix Hi-Z injectors, Aeromotive FPR, Racetronix f body fuel pump,MEGASQUIRT MS3 + MS3X Finally street tuned on 21 lbs! Now if only I could get it to hook....