Sputter, Sputter, Buck

[lasergst]

I just bought a 92 GST, titled as a Laser, and it runs pretty good if you turn quarter throttle or no boost. As soon as you add any boost to the motor, it sputters and bucks, the more boost-the more bucking. I put brand new NGK 6ES spark plugs,brand new wires, and brand new fuel filter. When I took the old filter out, I blew almost purple, muddy, liquid out. Any ways I have an aftermarket FPR, not sure what kind and not sure how to use it. It was on 4 on the guage when i brought it home, i took it up to 6 and it didn't get any better, but I could see the gas hand coming down. I need some help, I just bought this dsm and never had one, i have always had mustangs and camaros. Any help will be greatly accepted

By the way I have a aftermarket fuel pump and blue tip injectors, what size cc's are those I was told they were 450, but who knows if the guy I got the car from knows what he is talking about

Jonathan

 

[snailed]

yes the blue tops are 450cc, sounds like a its too rich. How much boost are you getting? I would first check for boost leaks by pressuresingthe intake system. when you leak boost the ecu enriches enriches the mixture according to the ammount of pressure you are supposed to be getting and if it doesn't end up in the cylinder hen you have a shitty mixture and it bucks like crazy.

cheers

 

[blackGSX2g]

What do the numbers 4 and 6 mean on your FPR? Are you looking at the fuel pressure gauge? Base fuel pressure on a stock 1g should be 37-39psi. You should have a pressure gauge on it, if not get one and set it so base pressure is 37-39psi.

Do you know what kind of fuel pump is in your car?

Also you should run a boost leak test on the car as well.

Yes, stock 1g turbo DSMs with a manual transmission came with 450cc blue top injectors.