I'm going to make this short and sweet.

What's happening?
When the ignition is on II, the fuel pump doesn't prime right away when the car has been sitting for several hours. When warm, the pump primes normally.

What I did to troubleshoot:
- New the spark plugs/wires
- Tested the fuel pump and the motor runs fine when hooked up directly to a 12v battery
- Took out the fuel filter to check the flow (ended up getting a new fuel filter)
- New main relay

What else is there to do? Any help is much appreciated.

Thanks

 

Any CEL codes? When the pump won't prime, does the CEL remain on steady with the key in ON(II)?

Have you tried cleaning and tightening the G101 ground wire attached to the thermostat housing?

 

No CEL codes, and the light stays on when the pump doesn't prime. I'm actually going to check that ground G101 right now.

 

When the CEL remains on steady, it generally means that the ECU has a power or ground problem. If G101 is fine, then check whether hood fuse 31 or dash fuse 24 is loose or damaged.

 

I had a little trouble finding the G101 ground. I took a picture of where I'm looking I will upload in a second.

 

Sorry for the newb question, but I checked both fuses 24 and 31... Fuse 24 I'm pretty sure is under the kick plate dash, and then you said hood 31.. I checked the fuse box under the hood and none of the sockets have a number next to them like under the dash steering column. Either way, the only fuse that's bad is the 12v cigarette outlet fuse.

 

 

 

Thanks, going back out to check the ground now.

 

I must be blind. I did not see any grounds on the thermostat. My car has a swap in it so I'm thinking the guy rigged it or put the ground G101 somewhere else?

And hood 31 fuse is supposed to be a 15a, and there is a 20a in there... Does that matter at all?

 

Post some clear pictures of the thermostat housing. It's important to find the ground location as this may be the problem.

Install the correct 15A fuse into the #31 slot.

 

I don't see any grounds on the thermo, and please disregard the hydra hoses going everywhere. I know the heater hose is kinked, but I don't even need the heater right now and my mechanic said that hose is useless.

 

If it's just missing the ground... wouldn't the car not run at all?

I have a P28 ecu maybe that's causing the issue like you said the ECU might have a power issue.