Author Topic: fuel pump or relay?? (Read 5563 times)

tampa e30 · « **on:** November 10, 2007, 09:44:56 AM »

Hello everyone, for a little background. I am restoring my wifes 1991 318ic which has become a slow process of late due to $$.

Anyway, I replaced the ICV this morning, went to start her, and no familiar hum from the rear. The fuel pump is not running now. So hence the title fuel pump or fuel pump relay??

I have a gut feeling it is the fuel pump but is there a easy way to check the fuel pump relay?

Thx in advance, Rich

ak96ss · « **Reply #1 on:** November 10, 2007, 11:54:14 AM »

Open the hood, remove the harness cover that runs along the back of the engine on the firewall, and pull the fuel pump relay. IIRC, it is the middle relay of the three there. Jump pins 30 and 87 with a fused switch. Turn on the ignition, then flip the switch on. The fuel pump will work now if the problem was the relay. If the pump still doesn't work, it's the fuel pump.

You can also remove the rear seat bottom, pull the inspection plate, and check for +12V at the pump connector.

You did check fuse 11, right?

RED IS 91 · « **Reply #2 on:** November 10, 2007, 05:32:54 PM »

when you put the key in the on position (the one before cranking) you should hear a click out of the relay.
If you don't then follow AK's advise.

tampa e30 · « **Reply #3 on:** November 11, 2007, 02:14:36 PM »

Thx for the responses.

Quote from: RED IS 91;37474

when you put the key in the on position (the one before cranking) you should hear a click out of the relay.
If you don't then follow AK's advise.

When I did the above, I heard 2 clicks from the relay. So that means the pump is bad??

Rich

RED IS 91 · « **Reply #4 on:** November 11, 2007, 03:36:19 PM »

If it were me I'd remove the rear seat and check for 12 volts at the pump with the key in the on position. If you have 12 volts there sometimes you can tap the pump with a non metallic (wood) object to see if it starts .If not then the pump may be the culprit.If you don't have 12 volts then jump the relay like AK said and check for voltage at the pump.
I have a feeling you need a new pump . How many miles on the vehicle?

good luck

tampa e30 · « **Reply #5 on:** November 12, 2007, 01:58:11 PM »

Yea, before I go drop $200 on a pump I'll check the voltage. The car has
120k on it.

RED IS 91 · « **Reply #6 on:** November 12, 2007, 06:25:47 PM »

Quote from: tampa e30;37541

Yea, before I go drop $200 on a pump I'll check the voltage. The car has
120k on it.

120K !!!!!!!!!!!!!! Just a baby ...............

good luck

Jimmy · « **Reply #7 on:** November 19, 2007, 10:08:20 AM »

Quote from: RED IS 91;37497

If it were me I'd remove the rear seat and check for 12 volts at the pump with the key in the on position. If you have 12 volts there sometimes you can tap the pump with a non metallic (wood) object to see if it starts .If not then the pump may be the culprit.If you don't have 12 volts then jump the relay like AK said and check for voltage at the pump.
I have a feeling you need a new pump . How many miles on the vehicle?

good luck

I had power to the pump but it was loose. When I would take corner or go over rough surfaces it would lose connection. I took off the plastic cover tightened the connector and plugged it back to the fuel pump. Works great now. I figured this out after replacing the fuel pump twice. Now I have a slightly used fuel pump reminding me to check the easy and cheap stuff first.

strad · « **Reply #8 on:** December 06, 2007, 12:23:02 AM »

Quote from: tampa e30;37541

Yea, before I go drop $200 on a pump I'll check the voltage. The car has
120k on it.

Mine got a replacement at about 170k just fyi

hoevesruperd · « **Reply #9 on:** December 06, 2007, 12:33:58 AM »

if you're going for a new pump, its worth it to buy a good one from germany. i thought i could save money by using a jobber and it lasted a month or 2. i ordered the one from bavauto with the complete harness and it seems to be good quality. though i've only put 5000km on it yet