1999 2500 with 5.7 Stumbles at idle

This is a new engine and has 13,000 so far.

It has plenty of power and pulls heavy loads fine but runs "rough" or "stumbles" at the idle. This only occurs at very low RPMs.

(I know that is a lousy description)

I thought maybe a bad plug or wire but that does not appear to be the problem.

It's very apparent when I shift into reverse for a slow backup but I don't think that has anything to do with the problem.

I thought maybe the fuel system but that's a WAG.

Any thoughts what to do next ???

Reply to
Pat Barber
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This is more of a S.W.A.G. since you only mentioned that the engine has 13,000 miles on it. You didn't say whether the fuel injectors came with the engine or whether they were transferred from the original engine.

So, my guess is that the fuel injectors need cleaning - rough idle would definately be a sympton of dirty fuel injectors.

Chevron Techron is a good fuel injector cleaner. Chevron recommends that you fill the tank about half full, dump in the contents of the bottle and then finish filling the tank to get a good mixture. General Motors has used Chevron Techron for a number of years, first just relabeling the Chevron Techron bottle and then under it's own packaging.

This is absolutely the best fuel injection cleaner on the market:

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The AMSOIL Performance Improver will do much more than just clean the fuel injectors.

Reply to
Steve

How many miles are on the injectors??

Reply to
Ashton Crusher

Pull the air intake hose from the manifold and clean out the built up gunk with carb cleaner or equivalent.

Reply to
scrape

I thought about the injectors myself.

The injectors came over from the old engine and as far as I know, have "never" been cleaned.

I need to get some of that Techron...

Who normally carries the stuff ???

How many "treatments" do I need ?

Steve wrote:

Reply to
Pat Barber

Reply to
Pat Barber

Does that work with the "throttle body" type fuel systems ????

A few other folks recommend injector cleaner.

scrape wrote:

Reply to
Pat Barber

Yes.

Do both. Total of about $3.00 and 10-15 minutes of your time for both.

Reply to
scrape

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