Truck air compressor busted?

December 28, 2006 8:25 AM

The air compressor on my 2002 Ford Ranger is making a really loud clicking sound every ten seconds when the heater or AC is turned on. The mechanic says this is normal. Is this normal?

1) I've been in a lot of cars and I have never heard a sound like this in a before. It's loud enough to hear going 70 on the highway. Both the heater and air conditioner work great.

2) I can see an air compressor turning on and off, but every ten seconds?

3) I don't think the air compressor is supposed to come on when the heater is turned on.

4) My regular mechanic is out of town, and I think the guy who looked at it is the "intern".

I'm pretty sure something here is not right. Does anyone with car smarts have any suggestions?

posted by worstkidever to grab bag (7 comments total)

I believe it's normal. My 2006 Mustang does the same thing.
posted by matty at 8:34 AM on December 28, 2006

your a/c compressor should not come on with the heater unless you have the window defroster on. Likewise, if you have the defroster on, and the compressor is rapidly switching on and off, that could indicate low refrigerant.
posted by M.C. Lo-Carb! at 8:55 AM on December 28, 2006

My 2001 Ranger does not (and did not) have that clicking sound. However, the a/c no longer works (leaks) and I am not willing to spend the $$$ to fix it. So, maybe it broke because it did not make that sound? Doubt it.
posted by JohnnyGunn at 8:58 AM on December 28, 2006

This may be related - but I haven't noticed any drop in RPM when my 'click' happens...
posted by matty at 9:55 AM on December 28, 2006

My '99 Ford Ranger did not have a clicking sound before or after I paid the $$$ to fix the AC two years into owning it.
posted by iurodivii at 10:04 AM on December 28, 2006

Matty, you put me on the right track. A couple of searches revealed that it is normal. It seems to be especially loud in the certain Fords. Also, in most cars, the compressor would not be engaged when the heater is on, but this model is wired differently. More details.
posted by worstkidever at 10:45 AM on December 28, 2006

I have an 02 Ranger and it bugs me. I was driving a 94 Explorer before this and it had a button with the Heat/AC control to manually engage/disengage the compressor.
If you wanted AC you had to engage it as well as set temp and vent selection. Sounds like a hassle but it was handy when the compressor went out and locked up, which temporarily locked up the motor. With the press of a button I could still drive unlike what I would have to do with the Ranger.
posted by sailormouth at 2:50 PM on December 28, 2006