zrs6v4

I have a 95 SC300 with 138,500 miles on it, and its an auto. I am having a very annoying rattling/knocking noise coming from the timing belt area. I was wondering if this symptom is a common issue with the 3.0 engines? here is what is going on-

1. I removed the timing cover and saw no issues with the timing belt and no lose plug wires either.

2. It really reminds me of a timing chain rattle known in Nissan 240sx engines.

3. It only occurs when car warms up to regular idling RPM's and when I rev the RPM's the noise mysteriously disappears and will reappear at idle only.

4. I carefully inspected the timing belt, fan, and pulleys and it doesnt appear for there to be any unusual contact.

5. There is no engine light or any unusual running issues.


any advice is appreciated.

zrs6v4

could this be the tensioner?

RyanV

iTrader: (9)

This is probably the serpentine tensioner.

Engine running-
take a screwdriver and put the tip against the serp tensioner and put your ear up to the screwdriver you'll probably clearly hear the tensioner spring giving up the ghost, which is common.

Its easy to replace, but don't over torque the 3 bolts. I think its 14ft lbs

zrs6v4

awesome thanks