Originally Posted by clinebarger
Sounds more like the Fuel Pump relay has given-up, These cars have a relay bypass built into the oil pressure switch......Once oil pressure builds to over 4 psi, It will send power to the fuel pump.
Yes , I discovered this , looking at the wiring schematics .
Locate the Fuel Pump "Prime" Connector (Red wire with a black plastic end on it) located near the fuel pump relay, It won't be connected to anything & it's sometimes taped to the outside of the harness.
Yes , I used this when I was diagnosing the failed fuel pump .
Start the engine. If the relay is operational....There will be NO power present at the Prime Connector!
OK , with the engine running , check from the priming connector to chassis ground ? If the relay is good , zero volts at the priming connector ?
*If it does have power, The relay is faulty or you have a wiring issue,
So if 12 volt + is present at the priming connector , then what is happening is the oil pressure switch is supplying 12 volt + to run the fuel pump . After the engine has cranked sufficiently to build up good oil pressure ?
Would be nice if it is just a bad relay . I have no problem with replacing it .
Along the outside chance of a faulty ECM.
Never considered a faulty ECM . Engine runs fine after it starts .
*Don't bother checking fuses as the power for the fuel pump comes from the same fuse regardless of the switch being used.
I have noticed the exhaust smells rich , until the engine warms up .
I have considered the 2 injectors may be leaking down over night . I ordered 2 rebuilt injectors , but have not swapped them out , yet .
The car starts normally , all day long , after the initial startup . If it was a bad relay , does that mean the engine is maintaining sufficient pressure to satisfy the oil pressure switch , all day long ? Vehicles I have owned in the past , that had real oil pressure gauges , the pressure appeared to drop to zero , soon after the engine was turned off .
Thanks ,