pathfinder engine help

independent361

New Member
Joined
Nov 19, 2007
Location
Greensboro, NC
I have a 1990 nissan pathfinder 4x4 and when im sitting in my driveway in park just idling my car revs up to 2000 rpms, then as soon as it hits 2000 drops down to about 1500, then raises back up again and drops back down. does this constantly when sitting in pack idling.

Any ideas??

Thanks, joey
 
Probably a muffler bearing going bad.....or, its trying to find itself.

Go to the Zone and have them look for any computer codes. That would be a good start.
 
Idle air control valve if it has one, or muffler bearing, muffler bearing are alot cheaper.

It could be intake leak.


The zone can't pull codes on pre obdII vehicles.
 
Hmm, I'm leaning against the muffler bearing. That will lead to a bit of a rattle when it tops to the high RPMs. Unfrtunate since the fix is easy and cheap.
IAC good possibility, definitely soudns like a vacuum pressure/regulation issue of sorts.

More in favor of the carb belt, a chronic problem on this year of vehicle.
Easiest test is to put one foot on the brake, press down hard. Now put it in gear, and give it some gas. If this makes the whole vehicle shake and lurch, you've got a problem.
Good luck.

EDIT - I see this post was just moved to a new locale.

Independent361, I'm going to suggest you search around to find the most common solution for these problems.
 
I dont know man, it sounds like a muffler bearing to me...

maybe just needs a good tune up? My 4runner use to do the same thing but stopped after a full tune up.
 
Back
Top