Car Won't Build Any Boost Without Stumbling/Breaking Up BAD!

[holmesboy]

Hi All. Having the hardest time with my 84 GN. Car will absolutely not build boost without stumble and falling flat on its face. The setup is 42lb. Injectors, TT Chip, Delco CR43 gapped at .32, Walbro Pump Hotwired, 86 ECM, stock MAF (was working fine), all Powerlogger numbers look good. Pulled a spark plug and it was black with soot after less than 5 miles on them. The car was running fine with about 10 psi of boost, then I added the Walbro so I could turn up the boost. That when the problems started. I verified fuel pressure on my Bosch 237 (looks about 41, line on) and it looks good, even rose with the barely 3 psi of boost I am able to get, then that's when it bogs out. Switched ignition module and coil, checked for vacuum leaks (none), not gonna change plug wires because the may be bad. The shortest tested about 2.5-3K ohms and longers tested 1.5K? Any other suggestions? Please help!!!

 

[BRAD_PADGETT]

Hi All. Having the hardest time with my 84 GN. Car will absolutely not build boost without stumble and falling flat on its face. The setup is 42lb. Injectors, TT Chip, Delco CR43 gapped at .32, Walbro Pump Hotwired, 86 ECM, stock MAF (was working fine), all Powerlogger numbers look good. Pulled a spark plug and it was black with soot after less than 5 miles on them. The car was running fine with about 10 psi of boost, then I added the Walbro so I could turn up the boost. That when the problems started. I verified fuel pressure on my Bosch 237 (looks about 41, line on) and it looks good, even rose with the barely 3 psi of boost I am able to get, then that's when it bogs out. Switched ignition module and coil, checked for vacuum leaks (none), not gonna change plug wires because the may be bad. The shortest tested about 2.5-3K ohms and longers tested 1.5K? Any other suggestions? Please help!!![/quote

Fuel pressure should be 43 line off with a TTchip. Spark plug wires have to ohm out within 10% of each other. The coil pak needs to ohm out between 10000 and 13000 across each tower. Do some homework and repost. Brad

 

[holmesboy]

New coil pack tested good. Will install new plug wires tomorrow. I will verify FP tomorrow, but I figured FP was close enough to 38 psi with line on. Could these few points off in FP be enough to cause what I am experiencing?

 

[holmesboy]

Hi again anyone who reads and can maybe offer any help!! Today, I verified fuel pressure, dead on 38 line on, 43 line off on Bosch 237. Taped FPG to windshield to monitor and pressure does rise smoothly up to the 3 or 4 psi of boost before bad stumble or stall (but car doesn't cut off), just no power and I have to let off throttle and ease back into. I have installed new plug wires, no change, uplugged cam sensor while running, no change, reset ECM, no change, tested all vac lines etc with carb cleaner, idle stayed the same. New I am posting two PL files on i tried to do a couple WOT pulls from a roll. While doing these pulls I noticed that I could kinda hear or feel air from turbo spool under the car dumping maybe? Again the last thing I did before this was install new Walbro FP, but it seems to be OK. I did notice that the MAF isn't near 255 ever. Please any suggestions would be greatly appreciated.