I was leaving the post office and the truck started to sputter. Seemed like it was out of gas. Then it was having trouble idleing and it wouldnt get up to speed. i had to barely touch the gas to get it going otherwise it shuttered like crazy. what do you think, blown spark plug?

Thanks
Mike

 

sounds like an iac problem, any tapping or exhaust leak noises?

 

It did sound like there was an air leak of some sort. Its stock accept for 3/4 belltech and 20's

 

Can't you tell if it's a plug by popping the hood and taking a peek?

 

Sticking IAC Motor or fuel pump hose came undone. Its one of the 2 I would get the truck to act up and tap on the IAC valve with a wrench if it stops running crappy theres your problem.

 

99 Ls are known to have a potential fuel pump problem where one of the lines blows off of one of the pumps. If it's starving for fuel, then that is a likely suspect.

If you here an exhaust-type noise, then it's probably a plug. Don't drive it either case as you could ruin(if not already) the head and you wouldn't be able to drive it safely if either one is the problem.

A dirty or worn IAC normally justs gives you a 'hunting' idle but drives OK above idle.

Dan