Just wonderin if anyones got some ideas on a noise my 91 has been making. Usually when warmed up.....and I'm in parking lot or just barely onthe gas(very light)....there's a tapping/clicking sound(not exhaust leak) coming from engine. If I step on the gas any harder it doesn't do it. This only happens under very light throttle such as goin thru parking lot. It is coming from engine thats all I know. Car has 194k miles....Runs very smooth and quiet otherwise.

 

could be an exhaust leak from your manifolds, did you check that? I can't really think of anything else it would be but I dont know all that much

 

valves possibly?

 

The valves would make this kind of noise? What causes this? its only under VERY light acceleration and at 1k-2k rpms.

 

Sounds like you're having a rough idle. There's another thread with the similar problem
http://forums.maxima.org/showthread.php?t=290424
Hope this helps..

 

Check your exhaust manifolds. Mine had pulled away and I thought the valves were loose. Low and behold, they're not adjustable. If its the front manifold you may not smell exhaust fumes. Look for missing studs. Also when you start it up put your hand next to where the manifold mates with the head, with the other hand rev the engine. If you feel any air at all against your hand, then it is leaking. As the engine heats up the manifold expands against the block so it doesn't allow the gas to leak. High revs will make it go away, too, though I don't know why that is.