# A/C Compressor or tensioner?

**URL:** <https://community.cartalk.com/t/a-c-compressor-or-tensioner/64111>\
**Category:** Maintenance/Repairs\
**Tags:** chevrolet, suburban\
**Created:** [April 27, 2011, 12:07am UTC](https://community.cartalk.com/t/a-c-compressor-or-tensioner/64111 "2011-04-27T00:07:15Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![v1v2fly](https://avatars.discourse-cdn.com/v4/letter/v/90db22/32.png) [@v1v2fly](https://community.cartalk.com/u/v1v2fly)\
**Post date:** [April 27, 2011, 12:07am UTC](https://community.cartalk.com/t/a-c-compressor-or-tensioner/64111/1 "2011-04-27T00:07:15Z")

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I have a 2000 Chevy Suburban. 229k well maintained. I had her (Buttercup) recently tuned up and drove on a trip of 1000mi. I started noticing a “rattle” in the range of 17-1900rpm after 500miles. The “rattle” sounded like a rivet gun being held against the engine block at the specified rpm. Additionally, the motor runs slightly rough at idle rpm all systems running. If I unload the a/c the motor runs smoothly @650-700rpm. The mtc rep said the compressor is failing and I should replace it immediately to the tune of $1500.  
  
  
  
 There’s one check they didn’t do and that was to check the tensioner to see if it had failed. The way I see i, if the compressor is failing, I would see it throughout the rpm spectrum…I don’t. Further, the a/c runs normally thoughout, even through the “rattling” phase.  
  
  
  
 What’s the probablity of the tensioner failing and the compressor is ok? I haven’t replaced the tensioner since I have owned her.  
  
  
  
 So, Whaddya think??

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**Author:** ![cigroller](https://avatars.discourse-cdn.com/v4/letter/c/c68b51/32.png) [@cigroller](https://community.cartalk.com/u/cigroller)\
**Post date:** [April 27, 2011, 12:56am UTC](https://community.cartalk.com/t/a-c-compressor-or-tensioner/64111/2 "2011-04-27T00:56:56Z")

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What you describe is exactly what I experienced a year or two ago in a 2000 model year GM vehicle…right before the tensioner pulley went kablooey.

Replacing a tensioner is an easy thing and not very expensive. At this age & mileage it doesn’t make much sense to not have it replaced - even if you find out it isn’t the source of the noise.

What is an mtc rep?

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**Author:** ![v1v2fly](https://avatars.discourse-cdn.com/v4/letter/v/90db22/32.png) [@v1v2fly](https://community.cartalk.com/u/v1v2fly)\
**Post date:** [April 27, 2011, 9:55am UTC](https://community.cartalk.com/t/a-c-compressor-or-tensioner/64111/3 "2011-04-27T09:55:25Z")

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Mtc rep is short for maintenance Rep. Sorry for the shorthand.

Thanks for the advice. I think I’ll replace the tensioner and the belt befor I go any further.