humpster

I have a 1992 GS300 turbo with a very irritating intermittent fault. The engine will not restart after a run of says 20min. This doesn’t happen all the time, just most of the time. The engine will turn over and cough into life but will run very roughly for about 45 sec then die. Or, the engine will run sweetly for 3-6 sec then die.
I have replaced the fuel filter, map sensor, fuel computer, engine computer, and fuel pressure regulator. None have solved the problem.
Currently the fuel pump is powered by a 12volt supply from the air purifier located in the boot. I have put a voltmeter across the plug terminals of the fuel computer and have noticed that there is a large voltage drop when the pump dies and I think it’s from the main 12v feed to the fuel computer.

My question is (and I hope like hell that one of you will know). Where is the fuel relay? I’ve got this funny feeling that the fuel relay could be the culprit. Why? Cos the other day my friend suffered the identical problem in his BMW E36…. the fault was a dodgy fuel relay.

Any help would be dearly appreciated

Jmai22

1992 eh?? must be the beta version of the car. lol j/k. well even though the gs only started production in 1993. i'm not really sure what the problem of your car is. it doesn't sound like a electrical issue to me though. sounds more of a mechanical issure. something to do with heat. when it cools down it will run.

humpster

Yip she's a genuine late 1992 Japanese import Aristo into New Zealand. It's definitely electrical cos the voltage drops away to the fuel pump to zero. Maybe.......a mechanical malfunction has caused an electrical component to produce faulty data to the ecu. It's got me beat?

2Lexos

have you checked the fuel pump? that's what could be causing the voltage drop.