Ac causing surging idle

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Ac causing surging idle

Post by mr.blub.blubs142 » Sun Aug 05, 2018 4:01 am

So I just developed a very odd problem and I’m hoping someone can lead me in the right direction. When my car is in park with the ac on, it idles super smooth. Once I put the car in drive, however, the idle becomes EXTREMELY rough, to the point of almost dying. The Ac still blows cold while this is happening. I had my girlfriend shift my car so that way I could watch what was happening under the hood, and I could visibly see the compressor rapidly turning on and off while this was happening. Is my compressor going bad, or is this a undercharge type of problem?

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Re: Ac causing surging idle

Post by Legacy777 » Tue Aug 07, 2018 5:40 pm

You really need to see the pressures in the AC system with a set of gauges to know what's going on.
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

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