96 S-10 bad fuel pump?

[Hobbes9112]

I have a 96 S-10 4.3 with 136,000 miles on it. Friday when I tried to start it, it wouldn't. It has power and tries to turn over, but you have to crank it four or five times to get it to start. Once it starts it runs fine. I talked to my mechanic on the phone and he thinks it is a bad fuel pump. I tried replacing the fuel pump relay and it still acts up. I am just confused because once you get it to start, it runs just fine. I figured that if the pump was bad, it wouldn't run at all. Could the pump just be on the way out? Is there anything else I should check before spending $250 on the fuel pump and pulling the bed off to replace it?

I have to get this thing fixed so I can sell it and pay for the 85 Jimmy I just bought! Any help will be greatly appreciated!

 

[86chevybanshee]

does it have cpi

 

[1979jimmy350]

it sounds like a realy you might want to check the one you got because it could be bad if not that you could have a short or open someware

 

[Hobbes9112]

Do you think I should try another relay? To test the fuel pump wiring, do I just disconnect the wiring to the fuel pump and put a meter on it?

 

[1979jimmy350]

it would be a good idea to try another relay. The way the system works is if the fuel pump relay won't work the oil pressure relay will not kick the fuel pump in until it reaches 4 psi which leads to longer cranking times. One way to test your fuel pump relay is to start the truck then unplug the oil pressure relay if the car dies you have a bad fuel pump relay. As for testing the wires i don't know exactly you might want to get a wiring digram and go off that

 

[Hobbes9112]

Well it has been a long week without my truck and I hope to tackle this job on Saturday. The relay I bought at the auto parts store is a lot smaller than the factory one, but it has all of the connectors. The original one is a large Bosch connector that clips to the firewall. I am going to try to get one of those from the dealership and see if that fixes things.

Before I try that, I want to try pulling the oil pump relay. The problem is that I don't know which one it is. There are four in a line on the firewall. My manual doesn't tell me which one it is. All I know is that the second one from the left (pass side) is the fuel pump relay. Anyone know which one is the oil pump relay?

Thanks a lot!

 

[dave_90_blazer]

there is no oil pump relay

you need to get a fuel pressure gauge on it to help diag

 

[Hobbes9112]

Fixed!!!

Got the truck fixed last weekend. I was so busy trying to end the massive oil leaks in my 85 Jimmy that I forgot to post back. Luckily it was just a bad fuel pump relay. I am very happy that I only had to spend $15 instead of $250! Thanks for the advice guys!

Brian