I got a slight problem

[wrecking-crew]

My truck is runnin' a little lean (noticed some piston material on the insulator due to detonation) and also idles at 1200 rpm before getting warm, but only drops to 1000-1100rpm when warm at a stop. It will sometimes drop down to 800-900 after a while.

 

[jhammel85]

I would start by checking the timing and then cleaning the IAC valve. Is it getting enough fuel pressure @ the fuel rail?

 

[gaz]

Not to grasp for straws

"wrecking crew",

If you have an automatic, this sounds very NORMAL to me. Your normal idle is 850-900 but after driving and then coming to a stop your cooling system will probably be working, which is a load on the system and may keep your idle up until you drop below the "driving temp".

See if this correlates to your coolant flowing (water pump, temp gauge) at the stop light. My water pump doesn't usually run even when the temp gauge is in the middle but past that the water starts moving and the idle rises (with my automatic).

Kevin

 

[WTF]

See if this correlates to your coolant flowing (water pump, temp gauge) at the stop light. My water pump doesn't usually run even when the temp gauge is in the middle but past that the water starts moving and the idle rises (with my automatic).

His idle is no biggie. I'd be worried about the plugs being fouled and chunks of "spatter" being on the porcelain! Make sure you've got the right plugs in there to begin with then knock out the steps Hammel wrote.

 

[wrecking-crew]

I am running autolite single plats.

I also need to mess with the distributor to see if I can fix the random misfire. I will also try cleaning the IAC and if I can find a fuel pressure gauge, I'll check that too.

I don't have a good timing light and can't find a FP gauge. I did clean the IAC, and it does idle smoother and better.

 

[Dangeranger3]

Running lean I would suspect a vacuum leak. An easy test is to have the engine running and spray (anything really carb cleaner, starter fluid, propane torch, anything flamamble) all around the gasket areas as well as the vacuum lines. If the engine revs, locate the area where you spray when it revs. That is where you have a leak.