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No Power Under 2500 Pms

Dank Xploidz

By Dank Xploidz
in Ask A GM Technician

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Dank Xploidz Enthusiast

Dank Xploidz

Posted
Posted

Ever since I have had my truck is is very weak on the lower rpms. It sounds like its bogging out but it doesn't want to cut off, just struggles to go, when I accelerate. When I accelerate it struggles but when it hits 2500 rpms it seems to go fine. It struggles to go up bridges and to pass people. I have changed a lot of things in the truck that could be the problem. I'll list them. Please help! Thanks.

 

I've changed the spark plugs, spark plug wires, fuel filter, distributor cap & rotor, O2 sensor, and sea foamed it. even tried to find vaccum leaks. It will crank up and idle fine, drives amazing other than that problem. Please help me

Stevens03 Senior Enthusiast

Stevens03

Posted
Posted

Welcome to the site. What gears do you have in your truck? You can find out in the glove box by looking at the RPO codes. GU6 = 3.42, GT4 = 3.73, GT5 = 4.10. A custom tune or a handheld tuner will help your flat spot alot.

 

Check out Diablo, Superchips, Blackbearperformance, and GoWheately for more information.

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

This truck has TBI right?

 

I think you may have an injector problem. Pop the air cleaner off and have a look at the spray pattern of the injectors...bring up the idle very slowly, and make sure its a nice fan pattern, not dribbling, or spraying off to the side or anything.

Stevens03 Senior Enthusiast

Stevens03

Posted
Posted

oops, didn't realize it was a '95. You'd need some kind of chip in that case. I know Jet chips work really nice.

 

What about clogged cats? That will cause a power loss :lol:

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Also make sure that someone didn't install an aftermarket TBI spacer -- they absolutely kill low-end power on these.

Dank Xploidz Enthusiast

Dank Xploidz

Posted
  • Author
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Do they come with stock spacers? Mine has a spacer, but without it the air intake wont go back on. I dont have a cat, my o2 senor was before it so it doesn't affect the power.

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

yeah...TB spacers are a good thing on a TBI vehicle and a carbureted vehicle...actually the only engines they do work on.

 

Anything that the TB only draws in air is where they don't work and kill low end. So 1999 and up for our trucks.

 

 

I would say check your timing.

10* BTDC at 2000 rpm is the right setting. Someone could have tried to advance it some more and screwed it up.

Do you have a timing light?

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

No no....a timing light is a tool....

Bring it to a shop and get the timing checked. Or if you have a buddy that knows what they're doing, have him check it. It takes about 5 min

Nytemare Senior Enthusiast

Nytemare

Posted
Posted

Low Power.

Especially if its too far advanced, it would have low power under 3000rpm.

You "may" also have rough idle if its way out.

 

you could also have pinging in the higher rpm range.

Nytemare Senior Enthusiast

Nytemare

Posted
Posted
Thanks, do you know if advance auto parts can check your timing?

No Idea...if they have a shop they should be able too...but I'm Canadian...we don't have Advance Auto Parts here...or if we do...not where I'm from.

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