Another rattle thread

[Sportrods]

I've searched a bunch of threads for this, but nobody is close to the same problem... This is on a friend's '92 Red MTX.


Car runs great, pulls nice, and drives fine. Fuel mileage is good, and it starts fine. BUT.... While driving(wont do this in neutral), any gear, between 2900 and 3900 RPM, there seems to be a light rattle. It sounds internal, but can't tell because I can't get it to do it while sitting still. It only happens under very light acceleration. Push gas harder, gone. Take foot off gas, gone.

What could it be?

 

[SASHO91]

how many miles are on the car???
what is the condition of the clutch, TOB, and what brand?
also, has any maintance been done to the car?
it could be rod bearings, but they normally make that sound at a little lower rpm....2500-3200 or so... IIRC.
without having known the maintance records, those would be my first guesses....

 

[Sportrods]

Excellent maintenance, 60k done at 71k and 128k, car has 135k on it. Clutch has 6k on it, and was done by a very reputable trans shop. The same place did the clutch in my SHO. It has a CM Stage I clutch.

 

[SASHO91]

It might be rod bearings....
can you describe what side it is coming from? or can you feel it in the floor boards??

you said the clutch is fine right? no hard shifting or anything???

 

[Sportrods]

It shifts kinda stiff, but it was checked by the trans shop again, and everything looks good.

It sounds like its coming from the drivers side of the car, but real close to middle. Dont really feel anything, its just audible. Thats why I was thinking that it wouldnt be rod bearings.

For notice, mine has similar maintenance schedule, and 131k, and I drove it at lunch and its doing almost the same thing, although much less and nowhere near as audible. Mine has a CM stage III in it. Could it just be a CM thing?

 

[Sportrods]

Well, I got ahold of a stethescope, its top end. Sounds like its coming from the valve train area. looks like someone forgot the stuff on the 60k! Looks like I got 2 to do!

 

[foshotime]

I have the same exact problem... CM stage I, 60,000 done a month ago, it clicks when i hit the gas real easy, or when i shift. I also have a blinking oil light. People say it is definetly my rod bearings.