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Tue Jun 17, 2008 9:27 pm

My engine didn't start 2x this past week. Both times it cranks over great. The first time ,it didn't start,it sat for 2 days and then it started right up like always. Drove it for 2 days. 2nd time it happened cranked great but didn't start.Seemed like no volts to the engine. I checked the + side of the coil and I had 12 volts. So when I tried starting it again I did not heard the hum of the fuel pump before the starter turned. Took off the hot wire on the pump and stuck it back on. I also wiggled the connectors in the engine bay. Then it started. It seems like my problem is in the powder to the fuel pump. If there is no power to the fuel pump will that circut not send current to the engine? Thanks guys

Glenn

Thu Jun 19, 2008 9:18 pm

little bump

Fri Jun 20, 2008 9:06 am

seems like maybe a ground issue??

I replaced my fuel pump a few months back and then started having problems... I replaced the fuel filter and checked all the grounds and cleaned them up.

That got it started without any problems.

Fri Jun 20, 2008 9:30 am

The fuel pump relay and the ECU power relay get their power from the small red wire on the starter. The path starts at the starter, makes it's way to the black box on the forward left firewall, on up to the fuse/relay panel and then back to the double relay box (left side engine compartment) where it powers both the fuel pump relay and the ECU power relay.

If the ground is not the culprit, I would check all of the connections along power route for breakage, loosness or corrosion.

Fri Jun 20, 2008 9:56 am

Something worth doing.

Hot wire the fuel pump. (as per P 20.19 in Bentley. For the Digijet anyways.....) If the pump works each and every time you do this, then the motor in the pump is likely ok, and likely the connections at the pump are ok.

This may also help narrow down where to look along the circuit as loogy has laid out.

Do you have a Bentley? Most helpful! :)

Neil.

Fri Jun 20, 2008 4:56 pm

Thanks guys.Yes I got my Bently but getting the laymans terms of how things works is very helpful.

Fri Jun 20, 2008 8:21 pm

My starting went intermittent, seemed to not like hot starts, cleaned off all the grounds (when the guy put in my new longblock he didnt bother) hasnt missed since.

Sun Jun 29, 2008 3:40 pm

I have a 91 Carat doing the same thing. It just started a few months ago. Replaced the fuel pump & filter, but still having the same issue. I have good spark, great fuel pressue, but still wont start after it's warm. Could this also be a grouding issue to the ECU?

Sun Jun 29, 2008 8:07 pm

70coupyel wrote: Thanks guys.Yes I got my Bently but getting the laymans terms of how things works is very helpful.

Well in terms of what I was suggesting, basically, if you remove the FP relay and "hotwire" the B+ "in" wire on socket to + "out" wire, it will send B+ to the positive connection at FP. This way you bypass the relay. i.e You are connecting positive (+) more directly to the + side of the fuel pump. (assuming ground is ok to FP) That way if the pump spins each and every time you do this, the fault may lie in the relay, or the connections to/from relay, and not in the FP itself.

If you wire B+ directly from the battery, then you are eliminating a larger "chunk" of the electrical system between the positive side of the battery and the positive side of the FP. BUT, this means more trouble shooting.

Hope that helps,

Neil.