Any thoughts. Thinking could possible be the IAC but not sure. TIA Nolan

What year and which engine? Have you tried a cylinder decarb on it? The IAC tends to have more of an effect when the engine is cold. I'd be more inclined to think possibly fuel pump, but would try a decarb first.

-Rod

03 V6 What exactly is a decarb.

It's to make sure your car doesn't get any ideas of going back to a carburator:) No:( It is the removing of carbon buildup on top of the piston and clinder as a result of incomplete combustion. I assume Rod was suggesting you get a fuel additive specifically for removing the carbon buildup. Your not having any engine pinging or knocking are you? I think Rod will correct me if I'm wrong you don't have to have a ping or knock just because you have enough carbon to cause other problems.

No there is no pinging just stuttering. I never thought about putting a bottle of fuel injector cleaner.

As tripledaddy suggested, I was referring to an additive to remove carbon in the combustion chamber and on the valves. What I've actually had good success with is the 1/3 can of SeaFoam. There are instructions on the can on how to do this. It basically involves getting the engine up to temp, then slowly pouring in 1/3 can of SeaFoam through an intake vacuum port. After you've poured in the 1/3 can, then shut the engine off and let it soak for 5 minutes (or is it 15 minutes?). Open up the doors to your garage if you're in the garage, start the engine after the soak, and walk away until the smoke clears (literally). If you get a lot of smoke, you had a lot of carbon and this make fix the sputtering.

Fuel injector cleaner as a preventative is also something I'd recommend, although there are differing opinions on this.

-Rod

Try the Sea Foam with the warning it'll smoke like a mother. Let it sit 15 or more in the warm engine. The start it and go for a spirited drive. You'll feel like James Bond with a smoke screen.:iceslolan

Is there anything harmful in doing/using that? I have two vehicles with carbs that I'd like to try that. Where do you put it in those? And, does the dose matter for 4 and 8 cyl engines? A mechanic friend of mine said I could slowly trickle water into the carb while its running to get rid of the carbon that the engine supposedly has, based on its poor performance and knocking on low grade and dieseling. After my arm got tired, I gave up and the problem persists.
Thanks for your input.

Being you have carbs you can pour it right down the carb's throat. You can get CEL after using these products but they usually clear after driving.

I think the only way it would be harmful would be if you poured the cleanser in too quickly. In that case, you could potentially hydrolock the engine and bend valves, but I don't think that would be too likely. The engine would probably stall out before that happened.

And yes, misting water in the carb would do a similar thing, although probably not quite as effective. That can be one indication of a bad head gasket. If you have a head gasket leaking into a combustion chamber, and it's leaking coolant, that cylinder and spark plug will be abnormally clean, no carbon whatsoever while others will have a definite carbon build up. The coolant leaking into the cylinder cleans it up quite nicely.

-Rod