Question about 1999 Chevrolet Silverado 1500

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Ignition miss under load

I just changed the fuel pump and filter but the problem still exists.It is like a ignition problem it will stuter and almost like a backfire through the intake.I'm gonna change the plugs but they are new too.

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  • gearjamster Feb 08, 2009

    i lose no coolant ,,my truck is new style so no distributor and it has new wires on every cylinder.I am told maybe a knock sensor will do this too.I will check my egr but i guess ultimately i need to scan to see why check engine light is on ...



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It sounds like you have some fouled out spark plugs. Sometimes when putting in new plugs you may inadvertently get a bit of grease on the electrode while installing them. It has happened to me. If that isn't it then check the rotor and cap. Theses should be changed along with the spark plugs. Spark plug wires are pretty expensive but if you have the cash then change them also. I typically change it all at the same time that way I KNOW everything is new.

Now here is something else to look for. Chevy is notorious for failing intake manifold gaskets. You can get oil into your coolant or coolant into your oil (Which is worse) or both can happen. If you have an unexplained loss of either oil or coolant (No visible leaks) then you may have a bad gasket. In many cases coolant can get into the valves, make them stick open and also foul out your spark plugs. Also look for what appears to be white grease residue in your oil. The best place would be on the bottom of the oil fill cap or dip stick. Look in the radiator for oil floating on the top of the coolant. In my case I didn't see any of these usual signs but still had a defective gasket. It all depends where exactly the gasket failure occurred.

I have had the exact same problem you are having and had to clean a white crusty substance off one or two of the same spark plugs every week or two to keep my truck running well. I had coolant leaking into my exhaust valve and fouling out my plugs. Look for this when you take them out. If you need to replace the intake manifold gaskets make sure you get the NEW and improved ones. This takes 8-10 hours if you know what you are doing. Good Luck!

Posted on Feb 07, 2009

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Check your EGR valve or your EGR sensor. That will cause those kind of problems

Posted on Feb 07, 2009


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