fuel pump

I have a 99 Blazer 4dr 4wd w/ 108k miles. Last night i went to start my car and it just cranked and cranked. It had driven fine earlier in the day. I tryed again to start it this morning and it still just cranked. I did notice that the usual sound of the fuel pump priming wasnt there anymore. I heard someone so on here that sometimes the pump will get into a dead spot on the gear or something? So i kicked the full tank 5 or so times and what do you know.. the car started and the sound of the fuel pump priming came back :eek: How long do you think this temp fix will last? Is it possible to just replace the sending unit and not the whole assembly? Thanks

I have a 99 Blazer 4dr 4wd w/ 108k miles. Last night i went to start my car and it just cranked and cranked. It had driven fine earlier in the day. I tryed again to start it this morning and it still just cranked. I did notice that the usual sound of the fuel pump priming wasnt there anymore. I heard someone so on here that sometimes the pump will get into a dead spot on the gear or something? So i kicked the full tank 5 or so times and what do you know.. the car started and the sound of the fuel pump priming came back :eek: How long do you think this temp fix will last? Is it possible to just replace the sending unit and not the whole assembly? Thanks

Yes, you can buy just the pump motor. You'd have to get it from a dealer, as most parts stores will only sell a complete aftermarket pump assembly.

Check www.gmpartsdirect.com for just the pump motor, about $90.00.
You'll still have to drop the tank and remove the whole assembly.

You know, in my op if ur gonna spend $90 and still have to drop the tank , why not buy a whole new pump? same amount of the labor

Not long. Once they go they go fast. I replaced my 1997 last year. Its a combo fuel sender and pump and its going again. Also, you have to drop the tank. Depending on how corroded the tank strap bolts are you may need them as well. Mine snapped off and I had to fabricate my own because it was a Sunday.....

Anyway. I just stated working for www.rockauto.com I know advertising probably isn't allowed in the threads but you can reach me at 866-762-5288 x231 and I can help you find a new pump if you like. I'm only posting this because I feel your pain!

There is also a test lead in the engine compartment to apply power to the pump if it does go bad again you can test it to make sure its the pump and not the relay or something else. The lead is on the drivers side. You'll have to dig for it. I know this from the chiltons manual I have....

Good luck/...

Thanks for all the quick replys. I think i am going to just replace the pump because i am kind of tight on money right now. Is this a easy job to do? I havent really done anything like this before. Biggest thing i have done is a water pump and wheel bearing assembly. But the fuel tank doesnt look like it would be to hard to get out.

Took me a whole day. Make sure your tank is near empty. I used a floor jack to lower it. Hoses can be hard to get off. IE Fuel filler hose. Don't break the connectors to the pump.

good luck.

I just tryed to drive the car up to the store. I turned the key to "ON" and heard the pump prime up. It started up fine. But when i was driving, if i took the rpms above 2k it would start to hesitate and act like it was going to die. Also when i would come to a complete stop the rpms would drop like it was going to die. Does this sound like my pump is just partially working? I looked for that test lead but couldnt find it. I want to be 100% sure its the pump that is bad before i go and drop the tank. Thanks

that lead is in there. I can't go out to my car to look right now but It's a single wire along the drivers side fender wall. Dig around a little more I'm sure you will find it.

When my pump went it did was yours was doing. I got lucky and it quit permanently in my driveway....

a whole day is way over exagerating... i did it in about 2 to 3 hours... not really a big deal.. the hardest part is getting it back it and lined up with the straps... ohhh and a big one, DO NOT FORGET THE EMISSION RELIEF VALVE AT THE FRONT OF THE TANK ON THE TOP has a small vac looking line running to it...

its almost impossible to see and will snap very easy.. and is 25 bucks at the dealer.

2 people is a for sure on this and a floor jack

I was one person, a floor jack, corroded strap bolts, closed autoparts store on a Sunday....hence the whole day....

:)

I was one person, a floor jack, corroded strap bolts, closed autoparts store on a Sunday....hence the whole day....

:)

As stated above about breaking parts,this will make the job go faster the next time. I got the whole process down to 2 hours by myself (taking the tank down 3 times, next time I'll do less than 1.5 hours):wink:

changed the fuel pump but it isn't pumping. Do I have to reset the computer or something? If so, how is that done?

Make sure your wiring didn't come disconnected when you hung the tank.

I would check your fuel pump relay in your glove box. There are 3 of them. You can swap one for another and see if it works. Then get a new relay if that's it. Check your fuses too.

Its gonna suck if that's the problem and you changed a pump for nothing....

changed the fuel pump but it isn't pumping. Do I have to reset the computer or something? If so, how is that done?

Find the TEST wire under the hood along the driver's side fender by the firewall. It's a red wire with a .250. insulated blade terminal on it. Put 12V directly from the battery Pos. terminal to it. You should hear the pump run.

Next,check you fuses (especially the ECM fuse).
Then as stated by 97Blazerlt, swap those relays around to elliminate them.

a whole day is way over exagerating... i did it in about 2 to 3 hours... not really a big deal.. the hardest part is getting it back it and lined up with the straps... ohhh and a big one, DO NOT FORGET THE EMISSION RELIEF VALVE AT THE FRONT OF THE TANK ON THE TOP has a small vac looking line running to it...

its almost impossible to see and will snap very easy.. and is 25 bucks at the dealer.

2 people is a for sure on this and a floor jack


HAHA i found my relief valve about 12 sec to late, I get the tank in teh postion to drop, and did just that, it ripped the end right off it. Luckly at the time i worked at a dealershiped and picked one up for 5 bux