1984tecate

Hey guys,
I've been having an issue starting my car.
1988 GTA with the 305 TPI t5
Wednesday night I filled up the gas tank and went home to park it for the night. Thursday morning I started it and it ran for 4 minutes and then stalled. It would not start but only crank. Later that night I tried again to start it but the battery was too weak.
Friday: I pulled the alternator because i figured that it may have gone bad causing the car to run off the battery. I had the alternator tested and found out that it was bad.
Tuesday: The new alternator came in and I installed it. The car started up and ran for 30 seconds and then it stalled as if I turned the key off. I kept trying to restart but I ended up flooding the car. I pulled one of the plugs and it was soaked with gas. I was able to change 2 of the 8 plugs since I cant get the other ones without the car being jacked up. Later that night, after letting the car de-flood, it started up and ran for a minute and then stalled. I started it up again and it ran for 30 seconds and then died as if i turned the key off. It started again and ran for 30 seconds and did the same thing. Then it would not start.
Wednesday: I bought a new battery and installed it. The car started up and ran for 30 seconds(running rough) and then it died. It would not restart. I was going to move the car so I could get it on ramps to change the rest of the plugs.

It's not giving me any engine codes, and I'm not sure what to do next.
Anyone have any ideas? Could it be the plugs or some sort of sensor?


Thanks,
Kyle

Tuned Performance

iTrader: (92)

Tbi, tpi , carb ? It might help the diagnostic if you state what your working on.

1984tecate

Its a 305 tpi with a t5

Tuned Performance

iTrader: (92)

Do you have spark ? Sounds like you have injector pulse if it was flooded .

1984tecate

It does have spark, just not sure if it loses spark after its running for a minute.

zed-028

i would now be looking at getting the ICM tested

Tuned Performance

iTrader: (92)

or check for rapid fuel pressure drop for stuck open injectors. Checking for spark while cranking and the accelerator pushed to the floor. This puts the ecm in clear flood mode and disables injector pulse.

1984tecate

just tried to start it. It only started when i had my foot all the way down. It started and ran on its own for 20 seconds and then tried to kill itself, i could keep it alive if i stayed on the throttle. Sounds like it could be an injector problem.

Tuned Performance

iTrader: (92)

You can pull the vacuum line going to the fuel pressure regulator . Look for it being wet. If that’s the case it’s a ripped fpr diaphragm. If not than do a pressure drop test. If the pressure drops rapidly after prime than its a injector stuck. I would replace the whole set if one is faulty and change your fuel filter at the same time.

1984tecate

Im still waiting on getting a fuel pressure gauge but I checked to see what kind of injectors i have and they might be wrong. I got the numbers D1810ba FJ25 off of the injectors, i did a quick search and it showed that they are 24lb's. If they are 24lb, is it possible that the cold weather has caused the car to not want to run if the car was never tuned? The car ran decent in warm weather but would serge and backfire if I came off of the gas to slow down.

Tuned Performance

iTrader: (92)

A 305 untuned with 24#hr injectors would run rich. There is a table in your tune for %change to air fuel ratio in open loop.

zed-028

plugged cat is also a possibility. eliminate the easy stuff first

1984tecate

So the fuel pressure gauge came in today. I hooked it up and turned the key on and it jumped up to 40 psi or so. It was losing pressure pretty quick, it was down to 20 psi within 3 minutes. I tried to start it but it wouldn't start. After that, when the key is off it is at 0 and when i try to turn the key on to prime it, the fuel pump turns on for a split second and raises the pressure to 20 psi and the quickly goes back down to 0.

Tuned Performance

iTrader: (92)

You might want to check pressure running, with as rich as it is sounds like leaking injectors.

1984tecate

What do you think would be causing the fuel pump to only kick on for a split second and the shutoff. When it comes on for a second it jumps to 20psi and then back to 0.
When i get the car to start ill check the running pressure

Tuned Performance

iTrader: (92)

There is a 2second prime each time the key is cycled.

1984tecate

So I was able to get the car started today. I turned on the key and the pressure read 40psi. It started up and the psi dropped to 32 psi. When I hit the throttle it would jump up a little. After it stalled, it lost all pressure. I turned the key on and it jumped to 20psi for a second and then to 0psi. Here's the video

1984tecate

Update: I found that the fuel pump relay plug was really greasy. I replaced it and the car started right, now the car idles around 250-400 rpms barely staying alive and it sounds like its running on 4 cylinders. It also backfires like crazy, but it starts up right away every time I turn the key. When I prime the car I hear no noise at all and my fuel pressure gauge is reading 0psi when primed and when the car is running. Does anyone have any idea what it could be? is it a very weak fuel pump?

zed-028

could also be an incredibly clogged fuel filter