2000 Silverado dies

[landerson]

2000 Silverado
5.3
260k miles

A while back the truck died on me driving down the road. It just stumbled a few times and then shut off. Acted like it was out of fuel. Drug it home and still would not start. Put fuel pressure gauge on, 0 fuel pressure. Bled gauge then cycled key to prime pump. Gauge read 40 psi, low but its something. Try to start truck and it fires right up. Assuming fuel pump is bad I go ahead and change the pump. All is good ~50 psi of fuel pressure.

Fast forward about 6 months and 10k miles to today. Same symptoms. Shuts off going down the road. Will not restart. Figure i would see if there is fuel pressure before I bother dragging it home again so I open the schrader valve with a small screwdriver and get a trickle of gas and a pssst. Try to restart truck, fires right up and drove it home. When I got home I put a FP gauge on it and fuel pressure is good. Ran fine all the way home.

What gives, some sort of weird vapor lock/air in fuel line? Truck gives no codes/ warning lights. It does occasionally buck a little when trying to accelerate at low RPMs. (for example when in overdrive at ~45-50 and try to accelerate it will buck slightly) Its been doing that for years so I'm not sure if its related. Otherwise it runs good.

Any ideas? I'm going to go ahead and change the fuel filter as its due anyway. Otherwise I'm stumped.

[j cAT]

fuel pressure must be above 53 psi. engine running. key on engine off 60-62 psi is what you should get. this is higher because the regulator has no vacuum. should not drop off on pressure quickly when key off.

with 50 psi you get loss of power and delayed starts. below 50 psi its dead.

with no codes this is what occurs with a fuel pump issue.

since it has a lot of miles and 13 yrs old replace the fuel pump relay.

replacing the fuel pump with some airtex etc type pump this is the normal failure of these defective pumps.

get a delphi or ac delco pump. make sure the wires to the connectors are soldered and sealed properly. replace the fuel filter.

[landerson]

Right now I get 51 psi engine off, key on. 45 psi engine running. Will drop slowly key off, takes maybe a couple hours to go down. This is the 3rd fuel pump for this truck. All three were Delcos purchased from the dealer.

Is it common for these trucks to eat fuel pumps? I got maybe 10k miles out of this last one. The original made it to 150k. Is there anything I need to look for?

[j cAT]

Originally Posted by landerson

Right now I get 51 psi engine off, key on. 45 psi engine running. Will drop slowly key off, takes maybe a couple hours to go down. This is the 3rd fuel pump for this truck. All three were Delcos purchased from the dealer.

Is it common for these trucks to eat fuel pumps? I got maybe 10k miles out of this last one. The original made it to 150k. Is there anything I need to look for?

sorry to hear of that failure rate. replacing the fuel pump with this amount of miles/age the fuel pump relay and filter must be replaced.the wiring at the pump must be properly soldered and the joints sealed [heat shrink].

keeping the fuel tank above 1/4 at all times. this should keep the pumps lasting like your original did. most times they fail around 170,ooomi area.

the dealership pumps could be chinese made crap. [clone copies]

the ac delco or delphi pumps most members have found to work quite well.

your pressures are low and match whats going on with your engines performance with this amount of pressure generated.

I would install a delphi pump.

how much did the GM pump cost ? what is the warrantee period ?

[ColoradoSilverado]

I replaced my fuel pump three times by now, first one was one of those cheap ones which failed within 30K miles, second was a Delphi which failed just after the one year warranty..., last one I got a Delphi again. I replaced the fuel filter all three times but never replaced the relay. Just turned past 242,000 yesterday and although this has been a very reliable truck to me (except for getting stranded twice because of the fuel pump) I will not buy another Silverado, the 2003 model is just plain ugly and technically the same as my 2000 model and the 2007 model.....no, just not my taste. Depending what the next model looks like I'll probably switch to Ford.....

[landerson]

Originally Posted by j cAT

how much did the GM pump cost ? what is the warrantee period ?

If I remember right the last one was about $350. I didn't pay attention to the warranty. It said ac delco on the box.

Thanks for your help. I'm going to go ahead and replace the relay as well.

Is there a good online source for the Delphi pump?

[j cAT]

Originally Posted by landerson

If I remember right the last one was about $350. I didn't pay attention to the warranty. It said ac delco on the box.

Thanks for your help. I'm going to go ahead and replace the relay as well.

Is there a good online source for the Delphi pump?

make sure that the ground is removed cleaned and secured next to the frame rail. low voltage or a bad ground can cause a pump motor to fail.Relay contacts get pited just like points in a distributor. then you get a voltage drop. the top of the tank is a bad spot for corrosion so the wire slicing must be perfect.

look inside the tank to be sure its clean. 350.oo is alot for that pump. you should find a delphi for around 200.00 or less. It has a one year warrantee that I have seen. even the dealership gives a one yr warr. I think .

[777stickman]

This is a good site for AC-Delco (GM stuff). Need to e-mail them your VIN so they can match a pump to it. As j cAT says, wiring connections and grounds are very important. These pumps need clean voltage to them and back to ground.


http://www.gmpartsdirect.com/