Fuel Management Issues

240shadow · Dec 10th, 2003, 04:32 PM

Started having ussues with the fuel Management on my 91 240.
The Fuel pump isn't getting the electric current it needs to function.
The relay isn't allowing the current to go though, I can take the connection from the relay that goes to the ECU and ground it to the manifold and the relay functions.
Is there anything along the lines of an inertia kill switch that can keep the ECu from grounding the line, or is there anything between the Fuel pump relay and the ECU that could interupt the current?

Any help would be great.

240shadow · Dec 18th, 2003, 04:01 PM

Found out that the relay for the fule pump isn't closing the switch to allow power to reach the pump.

Getting 34 when I run the fault codes which indicates the Knock sensor.

Does anyone know what sensors can tell the ECU to cut off the fuel?
I believe this is what is happening.

Thanks for any help

Nizmodore · Dec 18th, 2003, 08:10 PM

Sorry didnt see that b4...

No the knowck sensor will not cut of fuel, it just drops the ignition timeing back a bit....

Check your fuel pump relay etc......

BlueBOB · Dec 19th, 2003, 07:58 AM

the knock sensor being bad will make it seem like you're not getting enough fuel because of the fact that it's retarding the time... fix the knock sensor and your car will come alive... trust me

240shadow · Dec 19th, 2003, 12:02 PM

I have replaced the fuel pump relay and it made no difference
If the Knock sensor dies completely, will the ECU not close the pump relay to allow the power to get to the pump?