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Need Help. 2000 Mirage Surges when AC is on

I have a 2000 1.8L Mirage that has started surging when I try to run the A/C. I can feel the engine power drop and hear the A/C clutch engage and disengage when I try to accelerate. It was OK when I was only idling but the other day I sat in a parking lot and it would do it then also with the engine in park. I had attempted to recharge the A/C with a DIY kit (134a) that had a small guage inline with the dispenser. It read about midway in the good area. After that was when I noticed the severe surging with the engine. Any ideas about what it could be or where I need to look?

Thanks ahead,

JTMcD.

Reply to
John McDougald
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My guess is you have overcharged your AC. I believe the only way to properly charge a 134a system is to compare condenser discharge temp with high side pressure. Those hokey recharge kits sold a Walmart and other retailers that have only a low pressure gauge are a WAG at best. If your AC is overcharged, then the compressor's discharge pressure may be so high that your ECU is shutting it off to prevent damage. Some systems have pressure limit switches on the compressor that will open the circuit to the clutch coil. The higher the compressor discharge pressure, the greater the burden on the engine. If the clutch is being cycled on and off under these conditions, it seems engine idle speed would vary greatly. If the clutch is cycled at a fast enough rate, the ECU might not be able to keep up making the RPM swing even worse.

HTH Gyz

Reply to
Gyzmologist

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