My QX4 idles at very high speed and makes a high pitch noise. It does not improve durin or after driving it for a while. Can anyone tell me what it might be that cause this noise? It just started happening two days ago.
Thanks
99 QX4 is making very hgih pitch noise
Re: 99 QX4 is making very high pitch noise (qx4choi)
Welcome to NICO. The worlds ultimate resource on things Nissan!
Get a Factory Service Manual while you are waiting.
http://www.phatg20.net/modules...id=63
Sounds like Idle Air Control Valve is stuck or dirty and possibly a belt pulley for the noise or the belt itself is my guess. Could be the bearings on one of your accessories like power steering pump, alternator or air conditioning compressor. You could try cycling the AC and see if the compressor is more noisy when the clutch is engaged or not. Is it more noisy when you turn the steering wheel from lock to lock?
Hopefully a real tech will chime in and give a better answer.
Modified by burijon at 10:52 AM 2/16/2007
Get a Factory Service Manual while you are waiting.
http://www.phatg20.net/modules...id=63
Sounds like Idle Air Control Valve is stuck or dirty and possibly a belt pulley for the noise or the belt itself is my guess. Could be the bearings on one of your accessories like power steering pump, alternator or air conditioning compressor. You could try cycling the AC and see if the compressor is more noisy when the clutch is engaged or not. Is it more noisy when you turn the steering wheel from lock to lock?
Hopefully a real tech will chime in and give a better answer.
Modified by burijon at 10:52 AM 2/16/2007
Re: 99 QX4 is making very high pitch noise (burijon)
After further investigation based on your comments, I found out that noise drops significantly when I turn on AC. Also, it idles at above 1000 RPM. Any other suggetion.
Re: 99 QX4 is making very high pitch noise (qx4choi)
Sounds like you need a new clutch for the AC compressor or the bearings are bad.
Question for anyone reading this; are the bearings replaced with a new AC clutch? Does he have to replace the whole compressor?
qx4choi, you could call an AC shop and verify if the bearings and clutch are one and the same. If they are then it's a one stop fix. If not then you probably need a new AC compressor.
http://www.rockauto.com/catalo...up,24
In regards to the high idle, it may be that there is so much drag from the compressor that your engine is compensating. Fix the AC first and see if the idle sorts itself out. It's always a good idea to clean out your throttle body however.Good luck!
Question for anyone reading this; are the bearings replaced with a new AC clutch? Does he have to replace the whole compressor?
qx4choi, you could call an AC shop and verify if the bearings and clutch are one and the same. If they are then it's a one stop fix. If not then you probably need a new AC compressor.
http://www.rockauto.com/catalo...up,24
In regards to the high idle, it may be that there is so much drag from the compressor that your engine is compensating. Fix the AC first and see if the idle sorts itself out. It's always a good idea to clean out your throttle body however.Good luck!
Re: 99 QX4 is making very hgih pitch noise (qx4choi)
I had a high pitch noise at idel. Could not figure it out. This car was a mid west car so it pickup a bit of rust. The Main belt pully that to the connects to the crankshaft had rusted through and was squeeking like a stuck pig. Something else to look at. All in all the best car I have ever owned.