I need some help figuring out my electrical problem.

My fuel pump relay buzzes for about 5 seconds and then I get a high pitched whine when I put the car into the ON position.

Car is a 2001 auto with an LS2 swap. It was running fine last year until it was leaking oil at the rear main at the end of an open track day.

I drove it a few days later with no problems but some burning oil smell.

I filled it up to park it for the winter a couple months later but forgot the stabil. I added the stabil to a full tank and idled the car for 15 minutes to circulate to the other tank.

I drove it about a month ago and it was difficult to start but drove ok except at idle it was bucking a little bit like it was going to die and it was shifting harshly. I thought maybe the trans fluid was a bit baked from the track day and was shifting weird. I parked it for another month.

I then started it up to move it to my new place and it was again difficult to start. I got to the corner and it died. It took quite awhile to restart but then ran ok up to the gas station. It was a little over half a tank and I filled it up.

It restarted and I drove it to the new place ok and parked it in the garage.
Now, it won't start at all. It just turns over but won't fire. I changed the plugs thinking they were fouled.
I then got a Charge System fault message but I have no stored codes for my scanner. Using the forum I checked the connections at the starter, the wires under the battery tray and took the battery and alt in to be tested.

After putting it all back together I noticed the buzzing sound. I yanked the fuel pump relay in the main box and the buzzing went away when in the ON position. I swapped the relay with the RTD relay and the FPMP relay position still buzzes.

What would cause this?

Is my fuel filter plugged up and over loading the pumps? Changing that was going to be my next step.

Thanks much for any help on this.

 

I think I want to check out the fuel pump ground also. Can anyone tell me which ground location that is?
Thanks.

 

The ground for the fuel pump is back there close to it but truly, I don't know the exact position. I would imagine you should be able to follow the wires to it.

 

WHEN ANY RELAY BUZZES IT INDICATES THAT:

It is Bad or going bad... You swapped it out so that eliminates that issue.

It is NOT getting enough voltage to operate! That would be my first suspect. Meaure the voltage at the fuel pump fuse. On top of all the fuses, there are two test points. Measure both of those test points to GROUND! You should read full battery voltage on both of those TPs

If you read LESS than full battery voltage,, you eiher have a bad ground (located on the frame rail inside the drivers side rear wheel well. )

OR

The Ignition Switch output for that fuse is FUKED! (COMMON ISSUE) See what the fuse voltage is when you hear the BUZZING!


-C5 ignition Switch repair - http://forums.corvetteforum.com/c5-t...ch-repair.html

BC

 

Thanks Bill.

I measured voltage last night from the contact points in the fuse box for the relay with the relay removed and the 20 amp fuse for the pump directly to the battery ground. I got just under 7 volts.
Some other fuses I checked had a full 12 volts.

I sprayed the intake with some cleaner and it did fire over. So it's definately a fuel issue. I checked at the schrader valve with the car on and got a little "pift" of air but no fuel.

I got mideval on the passenger headlight ground connector and replaced all 9 wires with ring posts since I didn't know which location was for the fuel pump. Now I know it's out back thankyou I'll look at that. I know exactly which one it is. I think that location is too exposed to the elements in the wheel well so I'm not suprised.

I then tried to turn it over and it fired up and ran for about 30 seconds on its own and then died. I got low votage and charge system error displayed.

I decided to throw my large charger on it instead of relying on my built in trickle charger. It said the battery was about 40%. I let it charge for the next few hours and it was at 100%. It is a red top optima.

I'll need to get a helper to check the fuse voltage when buzzing.

I was going to pick up a fuel filter tonight since it's original anyway but I'll definately look into getting a new ignition switch or troubleshooting that if the filter, cleaned rear ground and charged battery doesn't work.

Thanks for your help. The weather is getting nice and I'm itching to drive it.

 

ITS NOT A FUSE ISSUE!!! Its the voltage that is coming out of the cefective ignition swith that your issue!!

Replace or service that ignition switch.

BC

 

Thanks Bill. I ordered a new switch yesterday.

I failed miserably at replacing the fuel filter but got plenty cut up in the process and lost a plastic fuel line disconnect tool either on top of the trans or in the metal under tray of the fuel tank. So it's a good thing it's the switch.

 

Got my new ignition switch installed. Hardest part was getting the center cover back in without scratching the dash or shift boot. Not difficult at all.

Car fired right up and ran great.

I took the old one apart based on Bills sticky. Sure enough the corner contact was almost completely black with carbon and the others had some spots.

I sanded them with some 600 sandpaper wrapped on a flat file and they cleaned up quickly. It was easy to take apart and put back together. I also added some more tension on the springs that push the fingers down.

If anyone has these symtoms don't bother to buy a new switch. It was easier than I thought it would be to clean it up. I could have been done within 2 hours start to finish with no new parts.

Thanks again to Bill for his insight into this issue.