[homefried1]

Coming home from Lowes yesterday with some sheetrock on my S10, and it just quit, like you turned off a light switch. I coasted into a driveway and tried to recrank it, it would turn over fine and would act like it wanted to start but wouldnt. Some really nice folks came by and asked if I needed help, they wound up calling some of their kinfolk who own and operate a rollback, we loaded up and took the truck to the shop.

My question is, will a fuel pump still make that sound they make when you switch the key on, if it aint pumping anymore? It acts just like it did when I ran out of gas recently. I'm hoping a fuel pump is all I need, that will fix my gas gauge at the same time if thats what the problem is.

 

[Tractor-Holic]

Usually electric fuel pumps work or they dont...some can be coaxed into running again by leaving the key "on" and using a mallet to give the bottom of the fuel tank a whack (fist works in a pinch sometimes too!)..

It could be you have some water in the fuel,and it froze up in the fuel filter--in that case the pump may still sound like its pumping,but it cant push the gas past the filter...it is possible for the impeller to break free from the motor shaft and let the pump run,but not move any gas also,but it doesn't usually happen frequently...but ice can make that happen..

 

[Alien5044]

With the gas line at the engine removed, the open end into a jug, key on, you should get some flow. If not, the line or filter is blocked or the pump is no good.

 

[Joelk]

My dad had an S-10 for about 15 years and I was the maintainer/repairer, and I had a couple myself. They seemed prone to Fuel Pump and or FP relay issues, poor grounds etc.

If you are in a quiet location and turn the key on you should hear the pump run for a few seconds, but only a few seconds. They are designed to only run for a few seconds when the engine is not running. If it does not run for a few seconds each time the key is turned on, it is probably the FP, fuse, relay or wiring/connection or possibly the ignition switch. Swapping in a different relay is easy/no cost way to tell if FP relay is the issue.

Depending on the year, the S-10s can be very sensitive to fuel pressure. I have seen where they would not start/run with 45 PSI, but ran fine with 55-60 PSI. Lots of stuff will run(but poorly) with low pressure, but my experience is that some S-10s don't run at all if the FP is even a little low. Fuel filter/sock could cause low pressure.

Alien5044 procedure will tell if pumping at all, but need a FP Gauge to see if making adequate pressure.

Depending on your situation, may be easier to pull bed than to drop the tank. Depends on how hard it is to remove bed bolts. 4 healthy guys can easily lift the bed off and wire harness can usually be unplugged easily.

Depending on where you are at, they can be total rust buckets and that can have a huge impact on how easy they are to work on. Take a close look at the tank, they rust out and now would be the time to replace if rusted and you are keeping the truck.

 

[dave_r]

Yeah, test and see if you are getting fuel at the engine. It may also have an inline fuel filter that could be plugged.

I know for my '04 Sierra 3500, the fuel pump can fail so it doesn't put out enough pressure for the engine to run properly.

 

[mopar65pa]

OK, well what year? Throttle body, EFI?
Go into the engine and find the fuel rail with a "valve stem" looking fitting and push the valve. Leave the door open and turn the key on to run. If you don't hear the fuel pump running for a few seconds crawl on the ground under the bed and kick the fuel tank, listen, kick again, listen. Do that 3 or 4 times. if you don't hear the pump run I suspect that is your problem.
Yes you can pull the fuel line off the output side of the pump and turn the key to see it it's working BUT you need to relieve the pressure at the engine or the ECU will not turn the pump on.

The late 80's mid 90's were bad fuel pump wise for every car maker.

 

[homefried1]

My dad had an S-10 for about 15 years and I was the maintainer/repairer, and I had a couple myself. They seemed prone to Fuel Pump and or FP relay issues, poor grounds etc.

If you are in a quiet location and turn the key on you should hear the pump run for a few seconds, but only a few seconds. They are designed to only run for a few seconds when the engine is not running. If it does not run for a few seconds each time the key is turned on, it is probably the FP, fuse, relay or wiring/connection or possibly the ignition switch. Swapping in a different relay is easy/no cost way to tell if FP relay is the issue.

Depending on the year, the S-10s can be very sensitive to fuel pressure. I have seen where they would not start/run with 45 PSI, but ran fine with 55-60 PSI. Lots of stuff will run(but poorly) with low pressure, but my experience is that some S-10s don't run at all if the FP is even a little low. Fuel filter/sock could cause low pressure.

Alien5044 procedure will tell if pumping at all, but need a FP Gauge to see if making adequate pressure.

Depending on your situation, may be easier to pull bed than to drop the tank. Depends on how hard it is to remove bed bolts. 4 healthy guys can easily lift the bed off and wire harness can usually be unplugged easily.

Depending on where you are at, they can be total rust buckets and that can have a huge impact on how easy they are to work on. Take a close look at the tank, they rust out and now would be the time to replace if rusted and you are keeping the truck.

Yeah, the fuel pump does make the sound when you turn the key on, thats why I wondered could it be the pump. Will it still make that sound if it aint working?

INCIDENTALLY, it is a 98 model with 4.3 and of course throttle body fuel injection.

 

[Joelk]

Yeah, the fuel pump does make the sound when you turn the key on, thats why I wondered could it be the pump. Will it still make that sound if it aint working?

INCIDENTALLY, it is a 98 model with 4.3 and of course throttle body fuel injection.

It could make sound and not work properly, but it means it is getting some current. Bad fuse/relay would supply no current.

I would start by checking fuel pressure(Can borrow gauge at AutoZone, etc.) and putting a new fuel filter on.

 

[homefried1]

OK, thanks to everyone for the help.

 

[homefried1]

OK, not the fuel pump! The dadblamed DISTRIBUTOR broke! The shaft in the distributor has a pressed on plate at the top that the rotor button is screwed to, it broke off the shaft! It had been making a noise similar to the sound that an old timey speedometer would make when the speedo chain was worn out, the guys at the shop thought it was gauges in the instrument cluster making the sound, and we had made plans to replace the cluster. They said that the cluster was a very common thing to mess up, in chevys.

The sound? They werent so sure why the cluster would make it but the tach jumping and the oil pressure being pegged over 80 pounds made them think that was it.

 

[Tractor-Holic]

I've read distributor failures are pretty common on older 4.3 V-6's...
Posts claim they have a plastic housing / bushing the shaft rides on that gets hogged out and causes failures like yours..the ignition module on yours probably triggers the injectors too,as well as timing the spark,either or both of the module's circuits can fail independently of each other ,or "come & go",work sometimes,then fail too..

 

[mopar65pa]