S-10 Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter · #1 ·
Have a 2000 S-10 4 wheel drive auto with the 4.3 that is having acceleration problems when cold. 110,000 miles. What I mean by acceleration problems, is that when it is cold and until it fully warms up it will occasionally stumble and generally be very doggy especially going up a hill or putting it under load. After it fully warms up it seems to be fairly normal. Idles fine- jumps up when it first starts then kicks down after a minute. I suspect that I might have an engine sensor going bad?

Also, the fuel pump is very loud- possibly louder than the engine- could the weak pressure cause it to cut out? When it’s very cold the pressure isn’t enough for a rich mixture? Fuel filter just replaced and *seems to be a little better. Starts right up, though I do always wait about 5 secs for the fuel pressure to build up before starting.

No DTC codes, no backfiring, no black smoke (at any point, even when it studders), does it while driving or while in neutral/park, so it’s not the transmission. No leaking fluids. Does have a very loose throttle cable, though I think the tps runs off of the actual throttle body so that shouldn’t affect mixture- also perfectly fine when warmed up...

Also only does it on the first start of the day, maybe more so if it’s sat for a couple of days.

Anyone out there have any ideas on what to look for and where it's located? Thanks.
 

·
B4U Task Force Admin
Joined
·
30,378 Posts
Moved to 262/4.3.

Check the sticky by Burned in this section.
 

·
Been there Done it
Joined
·
12,485 Posts
If your fuel pump is noisey you really need to test the fuel pressure. Most auto parts houses "loan" them.
Spec is 60 psi KOEO. It should hold at least 55 for a few minutes after the key is off.
 

·
Registered
Joined
·
10 Posts
Discussion Starter · #4 ·
If your fuel pump is noisey you really need to test the fuel pressure. Most auto parts houses "loan" them.
Spec is 60 psi KOEO. It should hold at least 55 for a few minutes after the key is off.
Thanks- I was thinking of just replacing it because I assume after twenty years it’s going to go out anyway. And a tow costs more than a new pump. Any recommendation on an aftermarket one? I’ve heard the OEM one isn’t the best choice.

Also I’ve seen you can remove the bed to get easy access to the fuel pump- does this work on the extended cab, and anything else I should look into while the bed is off?
Thanks!
 

·
B4U Task Force Admin
Joined
·
30,378 Posts
Thanks- I was thinking of just replacing it because I assume after twenty years it’s going to go out anyway. And a tow costs more than a new pump. Any recommendation on an aftermarket one? I’ve heard the OEM one isn’t the best choice.

Also I’ve seen you can remove the bed to get easy access to the fuel pump- does this work on the extended cab, and anything else I should look into while the bed is off?
Thanks!
20 years??? Sounds like a good pump to me. Auto parts don't last forever. the aftermarket pumps...no thanks. AC/Delco or Delphi.
 

·
Been there Done it
Joined
·
12,485 Posts
After 20 years it may not be the original pump.
If you loosen all the bolts attaching (6 or 8) the bed and remove the ones on the drivers side. The bed is easy to tilt up with a little help. There are some wiring grounds at the pump and tail lights that need to be unhooked first and the filler neck needs the 4 screws attaching it to the box taken out. The ones under the filler door.
You may have to replace the wiring connector as it was upgraded. It comes with cheap crimp connectors. I'd solder the wires and use marine shrink wrap since the connection is exposed to weather.
Don't forget the grounds when you're done.
 

·
Registered
Joined
·
381 Posts
I've been doing 14ga marine wire upgrades on alot of my pumps and other important stuff if anything looks even a little hinky. All soldiered and adhesive lined heat shrinked. I think it might have been you ODS that also mentioned this in the past. I picked up a big roll of double 14ga tinned pure copper wire on amazon very reasonable..like $40 for 100' iirc there were cheaper ones out there too but went for the speed and good reviews
 
1 - 7 of 7 Posts
Top