LS1 Fuel system
Thread Starter
Staging Lane
Joined: Dec 2009
Posts: 78
Likes: 0
From: sweden
LS1 Fuel system Hi
Are there any criteria when the PCM wont send signal to the fuel pump relay?
I just connected the pump 12V through a relay, and the green from PCM operate the pump relay coil. Worked fine until today.
Are there any criteria when the PCM wont send signal to the fuel pump relay?
I just connected the pump 12V through a relay, and the green from PCM operate the pump relay coil. Worked fine until today.
If the PCM doesn't see a crank signal it will shut off the fuel pump, but I think what you are saying is it isn't even priming, correct? If that's the case, check your fuses and grounds real good, my guess is that's where your problem lies if it was working fine and then suddenly quit. Could try swapping in a different relay just to make sure it's good since that would be an easy test, but I'm still leaning towards a wiring issue.
Thread Starter
Staging Lane
Joined: Dec 2009
Posts: 78
Likes: 0
From: sweden
Hi
Checked the fuses, swapped relays. Just fed the relay coil temporary from another 12 volt source. And iengine wont start! Something else is the issue here.
It worked fine yesterday. The only thing I did was working on the turnlights. Ign was on for longer periods. But I dont see this as the problem.
Looks like PCM dont send signals. How can I check this? Remove MAF connector and force it to run in "limp home" mode? Could this work?
Checked the fuses, swapped relays. Just fed the relay coil temporary from another 12 volt source. And iengine wont start! Something else is the issue here.
It worked fine yesterday. The only thing I did was working on the turnlights. Ign was on for longer periods. But I dont see this as the problem.
Looks like PCM dont send signals. How can I check this? Remove MAF connector and force it to run in "limp home" mode? Could this work?
Thread Starter
Staging Lane
Joined: Dec 2009
Posts: 78
Likes: 0
From: sweden
What I ment to say is, maybe the PCM need to have the relay connected to even send the signal? In this case I now why the signal to pump relay is lost, and even why engine dont start. But then I need to find the issue that started this. Can I see anything of this with HP Tuner?
