Philip Kwasinski

I recently got the air conditioning recharged on my 1996 Jeep Cherokee (all stock). Since then there has been an aggressive humming sound coming from the passenger side under dash when the A/C is engaged. Anyone have a fix for this?

PatHenry

So you're hearing the compressor kick on. Did whoever charged the A/C mention any concerns about the compressor (they would have definitely heard the compressor operate as they did the charging)??

If it's just a louder sound, but doesn't squeal, whine or growl, it may be normal.

I'd just double check with whoever did the recharge or swing it by a competent A/C shop and ask them how it sounds.

Red1992XJ

I put a new compressor in my other car, that seemed noisier than the factory compressor, so it may be normal.

Also, if the compressor is overcharged, I think it could make noise as well.

PatHenry

Don't forget to let us know how it turns out. Even if it's just worrying over nothing - your experiences may help the next guy.

Corky

Sounds bad doesn't it...One of the problems with having an older xj is the foam insulation that is placed in various areas of the AC system {blend doors,housing joints, etc...} begins to break down and ends up being ground up by the fan then shot out to what ever vent is convenient at the time...I'll bet you've got a big piece in there grinding away on the fan...See any small foam particles behind the vent grilles ??? Sometimes it flies out onto the seating compartment and you're left wondering just what it is and where it came from..I've been in a few XJs that sound like a harley when the AC was turned on !!