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2006 Ford Focus with a 2.0L L4 DOHC 16V engine. Idle slows down with AC on.
This vehicle rpm slows down and sometimes dies with Air Conditioner on. Only just after a cold start. Runs fine when warm with AC on. NO codes. Any ideas for testing?
The following user(s) said Thank You: aboudi.naddaf
Does this car have a throttle cable?
Sounds like it could be just a dirty throttle body. The IAC is already going to be open more during cold start anyway. Then it needs to open some more to make up for the drag of the A/C compressor. If The IAC is already near it's max open position because of dirty throttle plates/air bypass tube, it won't have enough left to keep the engine running with the extra load on the engine.
You can prove it by looking at IAC% on the scan tool. (Section 20 if you've got the book, or want to check out more videos)
Here's a ScannerDanner video on a different Ford with an IAC problem.
"Ground cannot be checked with a 10mm socket"
The following user(s) said Thank You: moggie4312, aboudi.naddaf
As above AC puts a relatively heavy load on the engine, it might be worth also checking the battery condition as a battery that is past its best can put a big load on the alternator immediately after a cold start.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
The following user(s) said Thank You: moggie4312, aboudi.naddaf
My friend got her car repaired. I didn't have enough time to really go in depth in to her car. The car was at her work ( parking lot) and not in my garage where I had more tools and time. She had been taking her car to a well known auto repair location and they took several weeks time to diagnose the problem ( no charge to diagnose). The shop told her it was a bad AC compressor and they did show her the worn parts. $600 repair cost. But that was one of the questions I asked her when I saw the car that one time. She said her AC was just fine cooling the vehicle.
I know its after the fact but I'm thinking it was just clutch.
The following user(s) said Thank You: aboudi.naddaf
I just went through a similar problem on my 1998 Nissan 200SX 1.6L. The compressor was going bad and I noticed increased drag on the engine , as well as some increased noise. The IAC did seem to compensate OK at idle, though, and it was only in the higher RPM's where I noticed it. It was also building high pressure at higher RPM's and clicking off...another indication of compressor coming apart and contaminating the system. I was reading through this thread and thinking it could be the compressor itself and then got to your last post where you said that was, indeed, the case. So, ti's possible it wasn't the clutch but the compressor itself.
The following user(s) said Thank You: moggie4312, aboudi.naddaf
Andy.MacFadyen wrote: Auxilaries can have a big effect on engine load Paul's MINI alterntor video is worth watching.
I've run into a few Lincoln Town Car and Crown Victorias that have come to the shop for engine replacement only to discover the alternator is seized up and holding the engine from cranking...
"Ground cannot be checked with a 10mm socket"
The following user(s) said Thank You: moggie4312, aboudi.naddaf
Andy.MacFadyen wrote: Auxilaries can have a big effect on engine load Paul's MINI alterntor video is worth watching.
I've run into a few Lincoln Town Car and Crown Victorias that have come to the shop for engine replacement only to discover the alternator is seized up and holding the engine from cranking...
"Ground cannot be checked with a 10mm socket"
The following user(s) said Thank You: aboudi.naddaf
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