When i come to a complete stop my truck sounds like a diesel

[BigSur]

I have had some rough idling lately but my RPM's haven't changed at all. I have replaced the fuel filter and air filter and checked for vacuum leaks. Nothing came up. My truck sounds like a diesel engine when i come to stop lights. I can't figure out if my belts are causing this or what. My gas mileage has actually gone up since i have replaced those two filters so it seems as though the engine is running good.

With the truck running i popped the hood and took a listen...it seems as though all my pulley's that are holding on the belts are squeaking but i wouldn't think a squeaky pully or belt would cause rough idling. I am kinda at a lost.

OH...this is on a 83' FJ60.

 

[fsusteve]

Adjusted your valves lately? Even when their right, solid lifters are noisy. Could account for rough idle too. If the belt squeaks, replace it and be done with it.

 

[Frederik]

check if all the sparkplugs are tightened! had it once with my (ordenary) car, and it sounded just like that.

 

[Jman]

Make sure the check valve on your air rail isn't creating huge exhaust leak in your engine bay.

 

[BigSur]

I have not found any vacuum leaks anywhere and the squealing sound won't go away. If i take a good listen it almost seems like the squealing is coming from the belt that goes around my power steering pump. But my steering is fine and it isn't leaking anywhere.

 

[60wag]

Squirt some water on the belts. If that affects the squealing noise, I'd just replace the belts. The belts shouldn't affect the idle unless one of the belt driven devices is on the verge of seizing. When the belts are off, spin each pulley by hand to check. Also check the ilder-like roller on the AC belt. The bearing in it can make some really weird noises.