The dealership told me I need to replace the serpentine belts on my 2002 QX4? (drive belts).

So, I went to Advanced Auto - they said it was a pretty easy job and sold me two Dayco belts.

I was able to loosen the tenionser pulleys, then release the tension from the bottom screw. After that it was fairly simple - just taking off the old belts and putting the new belts on - then tightening what I untightened.

The first day the belts chirped when starting the engine, so I went back under and tightened the belts and the chirping went away.

2 days later I'm noticing that when the car is in park or idling that the RPM's are at about 1,200 --- they drop down to about 700 when I put the car in gear --- however it seems to lurch and make noise - like it's causing the car stress to go from high RPM's in park to low RPM's when putting it into drive.

I know this can't be good for the car ---- what could the problem be? Are the belts too tight? I read something that maybe I could be off a groove on the belts? But they look correct....
Modified by gcjazz12 at 6:58 AM 3/9/2010

I've never been under the hood of a QX4, but I know that if you accidentally bump a vacuum line and it becomes disconnected it can result in a high idle. Sorry I can offer anything else, but I'd give a good look at the plugs and vacuum hoses where you were working.

WD

I think I may be imagining things.

It's revs high on first startup --- but it remains low throughout the rest of the drive, including stopping and putting in park along the way.

I do hear a squawking noise coming from the rear breaks when I come out of park into drive, or drive into park ----

My last visit to Nissan they said my brake cylinders needed replaced ---- so I'm wondering if something is up with the brakes....

Well if it only rev's high when cold then that's normal operation.