[urq] More URQ weird behavior

martin at quattro.ca martin at quattro.ca
Thu Mar 16 08:55:21 EST 2006


Sounds like you have a relay/wiring problem.
Only time ECU would shut the pump down is for the 4k RPM shut off or for
overboost.  If it runs the ignition it will/should run the pump.

> I now have 2 issues to sort that may or may not be related.
> Whatever triggers the fuel pump - doesn't.

The ECU triggers the pump and uses the same signals it uses to control the

> I can run the pump manually and the car runs fine. Shut off the override
> switch and it immediately dies.

This means you have a non ECU related issue.

> If I don't manually run the pump, it will catch and die. I can hear the
> pump
> run briefly and then shut off.
> I replaced the RPM flywheel sensor last night to no avail.
> What sensor is read to trigger the pump circuit in the ECU?

Both for start up.  Then only the speed sensor.  However this is probably
not your problem since ignition is functioning correctly (car runs).
SOme folks would install Coupe/4kq to "fix" the overboost or 4k RPM cutout.

> I have triple checked the fuse and the relay and wiggled the wires for
> both
> while cranking.

Did you check the relay for both, correct part and function?
Wiggling might not be enough if the brake is on the ECU end.

Also, check if during cranking, the wire from the ECU that controls the
Fuel Pump Relay switches to ground.

Hope this helps.
Martin Pajak

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