Hello Guys,

I need your help to try and figure out this electrical problem I have. The details are as folllow:

- 1998 Cavalier Z24
- When the ignition is in the ON position with the car off, the relay for the fuel pump
flutters (buzzing noise)
- The connectors on the fuel pump were cleaned and are tight fit
- The problem was present before I replaced my fuel tank
- I tried replacing the relay (interchanged with the A/C relay), no difference
- Once the car is started, the problem is no longer present
- I tried to fidel around with the connections under the fuse box to see if
a difference in the noise would be noticed. Unfortunately not

Anybody knows what the source of the problem could be?
What electrical connections should I look at, what sensors?
What's the next step to try and identify the problem?

Thanks!



SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -

sounds like a coroded wire between the relay and the pcm......a relay "flutters" because of low voltage or a bad ground. The PCM is the ground source, and the fuse to battery is the power source....check those two circuits first, you can use a DMM and measure resistance to ground from the PCM output trigger....should not be more that 2-4 ohms. and the battery feed should read battery voltage. if either is off, you found the problem circuit....start tracing wires!


If at first you don't succeed, destroy all evidence you tried!

Thanks Lousound,

This morning I had not time to take the air assembly out so using the ohm meter and other tools was not possible. I've attempted to locate the problem by wiggling wires in hope the car would NOT start. Once I would simulate the issue again, I would try and wiggle one wire at a time to locate the problem. It would seem the wires on the PCM side were my best bet. I will get more into this on Saturday. I'm hoping to find someone that has done car electric troubleshooting.

If anyone lives in the Acton area (close to Milton, Ontario) and would like a few cold ones, a meal and maybe a little money, I would sure love having you around.




SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -

Hello Guys,

I've spent some time on the car and the more I work on this issue the more I am lost. Yesterday I had to go to work, so I had to start the car. I turn the key to on and then try to start. No go, cranks but does not start. I then go to play with the wires and try again. No go. So I decide to turn the key to ensure I can hear the pump go. No I can't, so I keep going from off to on and off to on. Every 4 or 5 turns I get the pump to run. After having the pump go on 3 times, I decide to crank, and voila it starts.

Well this problem is anoying and there is an engine code that came up this time. Is there a methode to read the code without a OBDII scanner? Some cars have a combination of buttons you press to cause it to give you the code by blinking sequences or sometimes through the odometer.

Any clues you can provide me will be very appreciated.
If you know how to retrieve codes without a reader, let me know
If you live in GTA and feel like make a few $, having cold ones and a nice meal, let me know and I'll have you come here



SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -

Anybody knows if the fuel pump electrical system would be random if on the way out. Would it not work a second and then once the car started work normally?

Does anybody know what orders the Fuel Pump Relay to close the circuit?



SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -

what is your fuel pressure while cranking? does this only happen after the car sits?




1979 Impala Sport Coupe Aeroback

I haven't checked it because it happens even if I just had the car running.

Basically, get the car started, run for 5 minutes, stop, and try again. It will be to start again.

Idieally I have to turn the key to on a few time and wait for the pump to start. If it does not, I try again and once it does it, it usually starts.



SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -

i did not read your post well enough to see that the relay flutters KOEO, the relay the is ground all the time and the PCM supplies 12v to close the relay(grey and white wire). I would back probe the that wire with a test light and see if it flashs KOEO.

If it does the only thing left is the PCM but before replacing it I would check your powers and grounds with a volt meter. To test your grounds you must back probe the ground wires with your volt meter and go to a known good ground, If you have more then 0.2v droped on the ground circuit it is bad and that can cause a computer to do weird things and obviously make sure you have a good 12v to the PCM. Do this test KOEO.




1979 Impala Sport Coupe Aeroback

Great information.

I'm not sure what KOEO is. Can you tell me what that stands for?

I don't usually troubleshoot electronics so I'm learning as I go.

Thanks!



SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -

Sorry, I get it

Key on, Engine Off.

Eheheh



SoupMan

- and no, 'Soup' in SoupMan does not stand for Soup Up but for 'Soup' as in Lipton 'Soup'. -