S-10 Fuel Pump

[bob w]

I know how to build a rat rod. But I'm completely ignorant regarding late model machines.
Today I had to have my 2001 S-10 towed home on the end of a rope after our old boys lunch.
We're thinking it's the fuel pump.
Questions are:
1. How do I test to see if it is the fuel pump?
2. Any tricks on changing the pump?

There's several auto techs on RRR & I hope someone can give me some guidance.

 

[mako4r]

testing

Check the relay/change relay.
EFI fuse check/replace.
check for fuel while rotating throttlebody valve.
Some fuel pressure lines have a test valve much like an ac line does, If you are careful and wearing eye protection you could touch lightly w an object an see gas spray. Parts stores rent out tools to test. Chiltons would pressure "#'s".
Use a little spray bottle to put a little fuel in throttle body.Then system most be closed back up to try and start.

Remove the gas cap after cranking...listen for a vaccuum. You can also here pump when you hit the key.
If needing replaced take a good look at the fuel lines before removing anything If they are rotton don't attempt to remove tank until you have a complete assembly. If tank is full I've found it easier to remove beds sometimes if bolts are in good shape.,usually 6. Are local u-pull it sell assemblys for $15.

good luck

 

[bondo bandedo]

I did one about a year ago and these are the steps i took to do it.Really not that difficult to do but pulling the bed is the easiest way to replace at least it was to me.

 

[rockabillyrat]

a gm with a bad fuel pump.... say it isnt so.

only done about 35462235634634 of these.

going to make this really easy. pull the air cleaner off. spray in some carb cleaner. if it runs of fires for a second or too. then you know you have good spark and no fuel. there is a port to check fuel pressure on the rail if you have a gauge. if not push it in like mako4r said. next check power at the pump. test light works the best since its cheap and will tell you voltage and amperage (bright light) gm if i remember is the gray wire. turn on the key and look for the light. if all good put a pump in it.

pulling the bed is the best way if you dont have a lift to work with. you dont have to pull it all the way off. just unbolt it and swing it up so you can get to the pump. use an air blower to get all the crap off the top. then knock the ring off.

oh and replace you fuel filter. alot of the times they clog up and cause the pump to run hard and burn out. also helps not to drive low on gas alot.

filters on gm suck to get undone if they are the screw on type. if so i have a great tip. use an air hammer with a sharp tip. hold the line and then hammer on the nut of the filter so the blade runns with the line. this will spread the threads out and they always come off that way. this will save alot of time. that is if you have to deal with rust the way i do in ohio.

good luck

 

[rockabillyrat]

wow i just noticed every one that responded to this is from ohio.....weird.

 

[Gearhead10]

Check fuse first. If ya can reach the connector to the tank, usually thru LR wheel well, get a test light and test gray wire. If it lights up for just a few seconds when you turn key on then relay is good. Easiest way to change a pump is to remove the bed. About 6 bolts, wire connector to taillights, filler neck screws and a ground strap. Oh yea, a cherry picker or a couple buddies to lift it off. New pump for my s-10 was 75 bucks. Don't forget to install a new fuel filter at the same time. Most pumps dont go out, they get killed because someone never replaced the filter since the vehicle was new.

 

[bob w]

Thanks everyone for the very helpful information. I knew you guys would come through.[cl

 

[pegasus]

well its about time to swich to a holly blue pumb

whats that its to low psi?
why not go carbed
and if you go carbed might as well slap a 350 in it
(its scarry how i think some times...scarry but FUN!)

 

[R Pope]

I just cut a hole in the floor and make a panel out of another bed floor to cover it, like the manufacturers should have done in the first place. On a beater I just throw a chunk of plywood over the hole. Change a pump beside the road now!

 

[HOT40ROD]

Check the reset button first. They are design to shut the pump off when they are in a crash. Sometime they well trip for no reason at all or if you hit a pot hole,
You will have to check your owners manual for it location. The older ones were located in the PS kick panel area. It is usually a little black box with a yellow or orange button on it.
Check that first It may save you a lot of work.

 

[anvil]

when my 1988 s10 died I removed the bed and yes I will do it that way every time. turned out a wire wore threw,shorted out a reley and burned out the pump.three fixes and it was not that bad cause the bed was off and I could test drive itinbetwen the fixes . Other wise the tank would have needed to come out three times.

 

[cantwell.colton]

you should be able to hear the fuel pump come on when you turn the key forward to rght before the start position

 

[rockabillyrat]

Check the reset button first. They are design to shut the pump off when they are in a crash. Sometime they well trip for no reason at all or if you hit a pot hole,
You will have to check your owners manual for it location. The older ones were located in the PS kick panel area. It is usually a little black box with a yellow or orange button on it.
Check that first It may save you a lot of work.

sorry gm never had that. only ford.

 

[bob w]

I did one of those mystery repairs. Checked the valve at the fuel rail with the ignition on. No pressure. Pulled the relay and cleaned the prongs even though they looked fine. Put it back in and the truck runs like new.[S I'm leary that it will stay "fixed".

Thankyou for all the advice and information.

 

[rockabillyrat]

check the terminals the relay go into. could have a bad connection.

but im with you i have seen hundreds of pumps go bad on these trucks. only done a few that where electrical issues.

 

[old lady's mad]

heres one test thats easy and sometimes works . wack the tank with a rubber hammer . while some one is cranking the engine . if it starts , its bad . now another thing . if its bad , replace the harness conector that plugs into the pump module . they are to small from the factory and get hot and cause a bad conection . if not replaced now there a 50/50 chance you will have to do it again . fuel pressure is easy to check with a aguage . and there is what is called a fuel pump test conctor right be side the realy in the fuse/relay box . if it has power there the fuse and realy are good . and should have power to the pump without a cut wire in between .

 

[rockabillyrat]

now another thing . if its bad , replace the harness conector that plugs into the pump module . they are to small from the factory and get hot and cause a bad conection . if not replaced now there a 50/50 chance you will have to do it again.

all replacement pumps for gms come with the new updated connector. you have to replace it to use the new pump.

 

[bob w]

My mystery repair didn't last for more than one start. Monday I dig in. Let's say I was willing to cut a hole in the bed floor. What size hole would it take? How about location? Obviously, left front, but does anyone have a more exact placement? I sent a PM to R. Pope who has done that but no answer from him yet.
Getting under the truck is very difficult for me because I get positional vertigo and get very nausous if I slide under a vehicle.
Thanks again for all the helpful responses.

 

[old lady's mad]

all replacement pumps for gms come with the new updated connector. you have to replace it to use the new pump.

all aftermarket pump's come with updated conectors . you can still get a delphi unit to go back into it that still use's the original plug . i know this because the other moron at my work prefers to use them so he dont have to change the conector and take about 20 more min's to do the entire job .

cutting a hole in the bed , humm . well it would have to be atleast 6 or 8 inch's round and without looking under the truck and trying to judge where to cut you might as well cut a 12 inch sqaure in it . and it would have to be inside the frame rail but to the left of center not exactly sure the distance from the front of the bed or before the axle