Because a/c takes more power to run it. Try cleaning throttle plate on both sides and iac hole with choke cleaner see if that takes care of it
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Sunday, January 24th, 2016 AT 10:44 AM
MARIOC68
MEMBER
120 POSTS
I had already done that a few days ago but makes no effect. When the A / C is off smoothly all is well.
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Sunday, January 24th, 2016 AT 10:51 AM
MHPAUTOS
MECHANIC
31,937 POSTS
There should be an idle up for the A/C normally should be a vacuum switch that bypasses the throttle plate with the a/C on to idle up and help maintain a smooth idle
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Sunday, January 24th, 2016 AT 12:43 PM
MARIOC68
MEMBER
120 POSTS
TPS is normal that produce noise as hits such as tic tic tic. Sometimes?
Could be in need of a valve adjustment as I hear a lot of clacking goin on in video or sticky valves which I doubt or worn valve guides. Due to mileage it could be any of those
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Sunday, March 6th, 2016 AT 11:02 AM
MARIOC68
MEMBER
120 POSTS
Without a / c on, idle and then accelerating a bit and then releasing the accelerator:
IAC has any effect the control valve when idle when the A / C is turned on?
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Thursday, March 17th, 2016 AT 7:55 AM
HMAC300
MECHANIC
48,601 POSTS
Everything yu are showing on vacuum gauges are normal have you even tried adjusting valves or still questioning what we have suggested. I have no further comments.
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Thursday, March 17th, 2016 AT 9:26 AM
MARIOC68
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120 POSTS
I managed to repair the unstable idling.
The thermistor a / c each as active time on and off the compressor. Mine does about every 10 seconds.
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Saturday, March 26th, 2016 AT 8:59 PM
KEN L
MASTER CERTIFIED MECHANIC
47,536 POSTS
Hi I have seen this problem before and never found out what was wrong did you get the problem resolved?