Air conditioner rattling

[Car-Dog]

when I turn my air conditioner on any setting it rattles like crazy. The odd part is that if I put the car in park it stops. It only does it if the car is in drive or reverse. At first I thought my tranny had just self destructed but When I turned the air off the noise stopped. Any Ideas?

 

[Car-Dog]

Bump?

 

[Car-Dog]

No one knows why my air con might be rattling itself to death?
I know nothing about air conditioners so I am kind of lost.

 

[rhauf]

take a video and post it on youtube. i can probably figure out what it is if you do that. be sure to walk around the vehicle with the camera, so i can hear where the sound is coming from, what it sound slike in different places, etc. also slowly raise and lower the RPM and shift in and out of drive etc.

without the video ill take a couple guesses....

if the rattle is coming from the compressor, you may just need to add oil to the refrigerant (oil charge)

if the rattle is coming from somewhere other than the a/c system, it probably just puts a slight load on the engine, changing it's "vibrations" or whatever, exciting some resonance in a loose part, heat shield, or something and causing it to rattle.

 

[mbagley]

compressor rattle

check the four compressor mounting bolts, that attach it to the bracket. I had a 94 Ranger that did the same thing and drove me crazy until I bumped the compressor one day and saw it move!

 

[Car-Dog]

Thanks. Ill check that stuff out and try to get a video of the problem.

 

[Car-Dog]

Well I finally got a video of the rattle, and it almost sounds like it is coming from the Alternator. Anyone recognize this sound?

 

[Car-Dog]

know one knows what the rattle might be?

 

[ratgp]

yup, check you belt tensoiner and idler pulley

 

[Car-Dog]

I checked the tensioner, and even swapped it out for another tensioner i had, but it is still rattling. It really sounds like the alternator is rattling. is that possible? has anyone ever heard of a rattle in an alternator?

 

[ratgp]

yes it is possible that the alternator has a bad bearing,i would pull the belt and check each individual pulley for roughness or movement

 

[Car-Dog]

So I replaced the alternator (it had been making odd noises for awhile) hoping that it was what was rattling. I checked all of the pulleys their all fine( I replaced the idler and tensioner a few months ago) it still rattles just as obnoxiously as before. At this point I I am lost as to what it might be. and am getting ready to take it to my mechanic. Unless someone here as a brilliant idea in the next couple hours.

 

[Car-Dog]

I watched a couple videos on youtube and I am now convinced that my timing chain is what is making the noise. what do you think?

 

[ratgp]

ok car dog,first step,does it make noise with the belt off running,that`s how i would test it in our shop,if it doesn`t rattle, then it won`t be timing chain,next step would be to find someone with a special stethescope to pin point the noise, if you can`t find one of them i can suggest a lenth of garden hose around 18 inches long,put on end to your ear and start placing it be the alt a/c ect... to see where it`s the loudest,i hope this helps you find the problem

gary

 

[Car-Dog]

Thanks for your help, but I wound up taking to my family's trusted mechanic. I go back to college on monday and just ran out of time to do it myself. Once I start school again it has to running great or i am screwed because I have a daily 2 hour commute. I did try taking the belt off but the noise only occurs if you allow the engine to idle for 5-10 min and I didn't think my battery would like that very much. I also tried the old use a screw driver as a stethoscope and as far as i could it sounded like it was coming from the alternator I really appreciate your input and will post on here when I find out what the problem is. Oh and welcome to the board!

 

[nguyen_3]

I have the same problem. I have replaced the alternator twice (first alternator is a Duralast reman part, the second alternator is a New Duralast part). It's definitely the alternator, because when it rattles, I unplug the alternator wire harness and the rattle goes away.

Please help. Is it the cheap Duralast alternator causing this problem?

 

[hanibal21]

I watched a couple videos on youtube and I am now convinced that my timing chain is what is making the noise. what do you think?

the alternator is not original fordalternator by testing it,if you unplug it ,then turn on the car then the ac ,and noise is gone .

 

[nguyen_3]

I even got a used original Ford alternator, but the rattling is still occurring.
Car_Dog: I will try your method: unplug alt, turn car on, turn A/C on...I'll let you know what I find out.

 

[mamabear3]

Ever figure your problem out because my 2014 is doing that exact thing you described, especially when in reverse but only when the ac is on! So strange