Hi all.

so I think this is what's happening with my 91 V6 Firebird. On Sunday last week the car decided to not start. Or to be more precise it starts but runs for 2 seconds and dies.

I tried a few times and it's always exactly the same so it's getting fuel and spark but it's as if once the engine starts the power to the fuel pump is cut so it's just firing on the fuel that's been fed to the rail when the pump primes?

and I've got no idea where to start on this one! Any help greatly appreciated

 

Might be a bad fuel pump.

 

Sounds kinda like a VATS problem.

 

Nah I think the vats is ok as the security light goes off and the car does start and run then cuts out. I think it vats craps out it doesn't even engage the starter?

 

Well possibly. however it had a new pump fitted earlier this year. And I've had the rear carpet up and verified as he said he cut the trap door

 

Swap the fuel pump relay. It's on the firewall between the brake booster and the drivers fender.

 

What are you showing for fuel pressure at the tank and engine? Check to see if you have a fuel filter that might be the culprit, also you might have a deteriorated flex / rubber section of your fuel line choking the fuel flow.

 

Well it's running again. my friend came round and tried bypassing the fuel pump relay and it started and ran. even when he removed the wire!

Terminals on the relay looked nice and clean. put it back in and it started straight back up and every other time I tried throughout the day.

It's running pretty crap though. there a code 33, 34 and 35 lol. It's had a new IAC and a new MAP sensor but I did notice quite a few vacuum leaks. I sorted most of them. it still runs pretty crap.... yay....

 

Stick a new relay in there. They’re cheap.

 

Yeah A new relay is fine. I'm just onto all the other problems now that it's running

 

New relay turned up so I put that in today. Same again...it started and ran for 2 seconds and died. I tried again and it started and kept running though. Idle was still up and down and when I went near the throttle it died.

restarted and I let it warm up a bit and it seemed to smooth out and you can rev it fine. Still feels like it's misfiring though.

question about the IAC. Is setting one of them the same as the V8 where you switch the key on. Unplug it. Switch off then plug it back in?