romanianfury

First off let me say I have been a long time member of ltxtech and have exhausted all the advice from the forum members there; so I decided to come here and broaden my horizons in my reach for help. I really hope there is someone here that can help me figure this problem out. Thank you all in advance. And before anyone flames me, i did put a scanner on it and it said that the computer was not responding. I will list the story below and ive uploaded a video of the problem.

Story:

car is a 1994 camaro z28 m6. odometer reads 234,000 miles on it. was told by previous owner that the motor had been replaced. about three months ago i replaced the opti spark, water pump, and wires. checked the plugs and they were a bit black but i ran out of money so i kept em in. now on to the problems. the car seems to stumble throughout the entire rpm range. its not a misfire or a pop but more like hesitation. This happens regardless of throttle input. the stumble is similar to when someone lets out the clutch too soon in 1st and it jerks. now, when the car is at full operating temps and idles, it holds 20psi oil pressure or so but starts to bounce around up and down. ok update time. i checked and had one of the wires unplugged. put that back on and tested fuel pressure. with the key in "on" position, the fuel pressure read 38psi. with engine on idling it read 39-40psi. when the engine turned off it read around 30psi and fell very slowly. it still seems like the idle is weird, choppy, and weak. then at times the car turns over but won't start, during this time fuel pressure reads zero at shredder valve.

http://www.youtube.com/watch?v=NL1sBilhpR8

romanianfury

no one?

GreenBlood55

iTrader: (1)

Sounds like your having a fuel delivery issue. How old is the fuel filter? 234k miles and the fuel pump may be checking out. Check the fuel pump relay. etc..etc..

romanianfury

i just recently replaced the fuel filter and the fuel pump relay. i can hear the fuel pump prime every time i go to start it and can hear it operate as the car runs. im getting all kinds of opinions on this issue from bad maf or tps, to bad fuel pump or injectors, to even a bad pcm or ignition switch or bcm. any way to pin point an issue? i tried to pull codes today with an obd1 scanner and it said the system was not responding.

DisasterFormula

iTrader: (1)

There's a vacuum hose that comes off the fuel pressure regulator and plugs into the side of the intake on the passenger side. Pull that hose and check for fuel dripping out or a fuel smell. If you have either of those, your fpr (fuel pressure regulator) probably needs replacing.

warriorcustoms

iTrader: (10)

lt1 fuel pressure should be 43.5 @ idle & 50lbs a WFO I would say the fuel pumps shot USE A/C Delco all others will leave you stranded 200k+ on the stock pump is a lot lol most go out way before that IF you want an upgrade for mods later on get the Walbro 255lph w/ Racetronix hotwire kit & then your good for 500 to 600hp

romanianfury

I have pulled the vaccume off while running and it was at like 43psi and holding. I didn't see fuel coming out of it but didn't smell for fuel as the shradder valve had fuel around it any way. I will check on this and also pull the rail to see if injectors are leaking. What looks to be the problem though in the video? I will keep everyone updated. Thanks guys