I just installed a painless 60510 engine harness in my fully-stock 88 GT. When I turn the key for the fuel pump to prime, it doesn't stop after the usual 3-5 seconds. The pump stays on and there's a constant hissing noise from the lower intake passenger side fuel rail. I removed the upper intake thinking that It was a stuck open injector on cylinder 1 or 2, but I stuck a rod with a towel on the end down each lower intake port (all 8) to check for gas while it's priming and no wet gas spots from any of the injectors from inside the intake port. I was having issues figuring out how to wire everything with the inertia switch and kept using the old fuel pump relay circuit in the factory spot while having a new fuel pump relay provision included in the new harness. I finally got the pump to prime because I connected the red/black wire that comes from the inertia switch to the green 8 pin plug by the ECU to the injector power source wire. It now primes and I get fuel to the fuel rail because I pushed the pressure release and fuel came out. But again the pump doesn't turn off and I have that hissing noise until I shut the key back off.
Can using both the new and old fuel pump relays cause the pump to stay on? Does the fuel pump stop after the ECU sees optimal psi? since the injectors haven't sent any fuel into the engine, a stuck open injector couldn't be the culprit. I'm thinking that if the ECU needs optimal psi to tell the fuel pump to turn off. Could the hissing noise be an air leak causing the fuel system not to build up enough pressure, therefore, keeping the pump on? I also see 30psi of fuel pressure at the Schrader valve so I'm stumped.
I would send a video of the hissing noise from my phone but It doesn't allow or I just didn't figure out how. All replies are appreciated.
Thanks.
Can using both the new and old fuel pump relays cause the pump to stay on? Does the fuel pump stop after the ECU sees optimal psi? since the injectors haven't sent any fuel into the engine, a stuck open injector couldn't be the culprit. I'm thinking that if the ECU needs optimal psi to tell the fuel pump to turn off. Could the hissing noise be an air leak causing the fuel system not to build up enough pressure, therefore, keeping the pump on? I also see 30psi of fuel pressure at the Schrader valve so I'm stumped.
I would send a video of the hissing noise from my phone but It doesn't allow or I just didn't figure out how. All replies are appreciated.
Thanks.