Hi all.


Have a 95 E250 6 cylinder. Tried starting vehicle one morning and it wouldn't start. Had ignition module checked, checked good, but noticed fuel pump wont shut off. Checked fuel pump relay, checked good. Tested voltage at relay receptacle, and noticed 12v will not go away with ignition on.


Tested fuel pressure, pressure is up to specs, with ignition on and while running. Removed air intake assembly, sprayed some fuel in it, vehicle will start and run, but attempt to accelerate while standing still, produced fuel starvation, but will keep running when taking the accelerator off. Can run rpm to a reasonable amount, but pressing accelerator quickly will produce stalling.


Suspect engine control module. Removed ecm and found no obvious component problems, all electrolytic caps look ok, no hot spots anywhere.


I'm an old automotive tech from the 60's 70' and 80'. I'm also an electronic tech.


Does my sucpicion of bad ecm, sound reasonable ??


Also forgot to mention, I cant read ECM with OBDI reader, or manually by jumping at connector.


Thanks for reading.


Roy

 

Maybe I can help, MAYBE !
When you turn the key on it is supposed to energize the EEC relay which supplies power for the fuel pump relay, but the computer (ECM) provides the ground to pick the fuel pump relay for 2 seconds unless it sees an RPM signal from the dist when cranking. It may be possible you see 12 volts at the FP relay because you are seeing the power supplied by the EEC relay. The FP relay when the pick side is grounded manually should cause the fuel pump to run. That does not seem to be the problem from what I gather.
A shorted or weak coil will break down under load and produce the symptoms you are seeing.
A plugged fuel filter will also do a similar thing, have you checked if the fuel filter is plugged ? As you know, pressure can be there , but volume can be insufficient.
Don't feel bad, we all need reminders and in my case , Often!

 

Ok it was what I analyzed and suspected, the new computer fixed it.


Now I still have a 99 that I rebuild the injectors and installed new pump and tank, but still has something not right, starts ok, but acts like it has a bad accelerator pump if it was carbureted.


Need to look to see what code it pulls.


And I got a 2000 that's been sitting a long time, that probably has a screwed up fuel system, dang alcohol fuel.


Thanks for the help.


Roy