Looking for some guidance on a fuel system issue:

I just had the fuel pump relay replaced on the JBE, but there is still no voltage coming off the pins on the JBE.

I’ve checked all the fuses and other relays on the JBE and the DME.

There is power going to the JBE because all of the other electrical systems appear to be functioning correctly other than the fuel system.

What started as a high pressure fuel pump issue per the initial code has sent me on a wild chase that’s now four months old.

Any help would be greatly appreciated.

Aaron

 

Have you checked the voltage at the in-tank fuel pump? Make sure power is getting there. No power at the tank, no fuel.

 

If you have power at the JBE, have replace the relay, and still aren't getting power out to the fuel pump FROM the JBE...I'd suspect that the issue is the JBE itself.

 

njaremka,

I had already checked and knew there was no power at the tank, which is why I was asking about the voltage coming off the JBE.

Turns out there is a grounding issue between the JBE and the DME, which was preventing voltage engaging the fuel pump relay. I was able to hotwire the ground and get power to the low pressure fuel pump.

However, when I try to start, I'm still not getting fuel to the HPFP and have this message: Engine operating at reduced output.

Now, I'm left wondering if the DME is bad.

 

Post all current fault codes that repeat after clearing codes with a scan tool. Did you directly measure pressure at the fuel rail or does your scan tool read 0 psi at the fuel rail?

 

4th Gear,

The original fault code was 2C03 High Pressure Fuel, Plausibility Too Low. In order, I replaced the fuel rail sensor, HPFP, LPFP, and then the fuel system relay on the JBE. I knew there was no fuel pressure because I was not getting power to the LPFP.

It turned out to be a grounding issue between the DME and the JBE. When I "hotwire" the fuel circuit, I now get voltage to the LPFP.

Now my concern is the DME. Does anyone have any sure-fire ways to test the DME? When I try to start it, I continue to get this error: "Engine operating at reduced output."

I'm hoping to learn a way to confirm the DME is faulty before I send it off too.