When I turn my A/C on my engine stumbles intermittently. It doesn't always start doing it right when I turn on the A/C, sometimes in can take a while but it eventually happens. If I am at idle it will drop the revs down to around 500 RPM for a second or two and then go back to regular idle. It will idle fine and then repeat the problem 30 seconds to a minute later. If I am driving I can feel the revs kind of drop and the engine stumble a bit. This problem also occurs when I have the defrost on (but I'm guessing that's only because when the defrost is on the A/C comes on too). Any suggestions?
Engine stumbles when A/C is on
- Thread starter igidy
- Start date
You are correct, with all system when you turn the front defroster on it does activate the AC compressor. Now there are a couple things tocheck, does your engine drop rpms when you turn your head lights on? I had a similar problem in my old P5, turned out it was my alternator.. I am not sure how mechanically inclined you are but you can check the volts comming off the alternator very easily with a multi meter. As well check your battery.
so, driving home from work i didn't notice a thing. its 100 outside and I had it full blast. during lunch it was doing it quite a bit. I notice when the problem comes on that my AC does not come out cold. and the stumble happens at regular intervals... not just randomly. i think the EGR would do it all the time right? not just when the AC is on.
tweety2300
Member
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- 2001 mazda protege mp3
My car does the same thing I though it was normal? All the cars I've ever had have done it. It just does it onces the ac fan will turn on but itl go back to normal within a second or 2
i had the same problem, what i did was clean the battery terminals and connectors, it actually helped a lot! the car would basicly fall on its face when i was idling with the ac on... now rpms still drop a tiny bit but its almost hardly noticable at all! but since it still does it a little (and my windows seam like they are tired when i open all of them at the same time) i am going to install a full ground kit...
there is a write up in the how to section that ima follow step by step
there is a write up in the how to section that ima follow step by step
When your AC compressor cycles on and off it will initially rob a few ponies to get going. Feels like ignition miss. (miss fire or stumble) These little 1.6L,1.8L, 2.0L just dont have the HP (most of you 130hp or less) for you not to notice the compressor. Try to duplicate with AC/defrost turned off.
the thing is that its not just when i turn my ac on. in fact it doesn't happen right when i turn my ac on. it happens after driving for 5-10 minutes after warm up. it happens at all revs(idle up to redline). and when it does happen, it happens at regular intervals. you could probably count regular intervals between each engine stumble. it goes on and for about 5 minutes at a time. then takes a 5 minute break...and comes back. when it is doing it i notice that the AC is not cold.....any ideas?
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Does it happen when the AC/Defrost is not on at all? Turn everything off and see if issue persists. If it persists you may have missfire under load and need to start looking in that direction. If it doesnt I would say that your AC comp is on its way out or you may have a blockage in the AC systyem. Regular intervals might mean when the comp cycles on and off
Have you cleaned the EGR and IAC? Have you seafoamed the engine lately? Maybe you have a short in a wire somewhere. I had a very similar problem and turned out to be a short in the wire goin to the IAC. Car would stumble intermittenly until I replaced the wires and plug
It was actually rite at the plug where the wires went in. Give it a try, then u can at least rule that out. Just let the car idle and gently wiggle some wires
so i figured it out (i think). it only occurs when my A/C is set to level 2. one day i noticed when i switched over to level 2 the green light on the switch indicating that A/C is on on went off. it soon came back on. while i was driving i noticed that the green light would flicker every now and then. when it would flicker i would notice the stumble. so basically the problem is that my a/c is literally going off and then back on which is why it is stumbling. i'm guessing the problem is in my control knob itself but i have not verified this yet. this only happens on level 2. as a temporary "fix" i have just been using all other levels. if anyone has any experience in checking the function of the knob i would love to hear about it. Thanks
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- 2010 Mazda5 GT
You know about the infamous A/C issue with the fan dial right?
http://www.mazdas247.com/forum/show...ion-To-Flickering-Fan-Speed-2-Or-3-A-C-PART-2
http://www.mazdas247.com/forum/show...A-C-compressor-problems-at-fan-speeds-2-and-3
