I have a 2000 Honda Civic 1.6L iSR MTX that I bought recently and replaced the engine in. Haven't driven it much, but got the impression the A/C was not working so well. However, I took it on a long trip recently, and on the first 230 kilometers the A/C worked beautifully. Then I stopped someplace, got back in the car to drive again and saw the A/C wasn't working at all. As in the A/C indicator light comes on, air blows, the A/C radiator fan comes on, but the air's not being cooled at all.
What I noticed was that when I engaged the A/C, I didn't feel any additional load being put on the engine. Normally, I would expect to see and feel a slight dip in rpms as the compressor comes on, but before the IAC opens up to compensate.
This lack of any noticeable additional load and the fact that the A/C operated beautifully for the first 230km of the trip makes me suspect the compressor clutch isn't engaging for some reason.
Does this seem like a reasonable guess, how can I verify this, and what are my repair options? Is this a diy kind of job?
I just took the car for a drive and decided I'd try the A/C again just for the heck of it and it started up and gave me nice, ice cold air. When I stopped to park, I did a little test where I turned on the fan full blast, waited a few seconds for the rpms to settle, then turned the A/C on. This time I could feel and hear the compressor engage with a kind of clink. Yesterday when it wasn't working I had the hood open and was standing right over the compressor when I had my wife turn on the A/C, and I didn't hear anything.
So it seems like I've got some kind of intermittent compressor issue. Maybe a loose wire preventing the clutch from engaging? What should I check?