Can anyone help with a 1992 Honda Civic A/C Problem?!?

Question

My '92 Civic keeps dying and runs very rough whenever the air conditioner is on. I had the A/C modified to the R134 a couple of years ago. The car runs great (37 mpg city) without the air on - but it is getting pretty warm out!! Does anyone have any idea what is going on? thanks

Answer 1

There are three common possibilities.
the first and easiest is that the car may have forgotten how to idle (it happens!). To teach the car what the idle should be, disconnect the negative cable from the battery and leave the cable off for about 10 minutes. Then, reconnect the cable and use the following procedure to 'teach' the ECM the new idle:

To allow the ECM/PCM adaptive idle speed
system to learn and adjust the engine idle speed,
here’s what you do:
• Make sure all electrical items (A/C, audio unit,
defogger, lights, etc.) are turned off, then start
the engine.
• Let the engine reach its normal operating
temperature (the cooling fans cycle twice; the
coolant temperature is about 194° F).
• Let the engine idle for at least 5 minutes with
the throttle fully closed and with all electrical
items turned off.
• If the cooling fans cycle on while doing an
adaptive idle learn, add the time the cooling
fans are on to the 5 minute adaptive idle learn
time.

the second possibility is that the idle is set too high

• Check the base idle speed setting (with the idle air control valve disconnected). It should be set at the high end of the
spec (470 rpm). Do not set it higher than the spec. You need to use a tachometer to set the idle and you adjust the idle by turning the idle set screw.

There is the possibility that there is a carbon build up in the passages of the idle air control valve. You can usually take the valve off and clean it with carburetor cleaner and a pipe cleaner.

A fourth possibility is a contingent possibility--You didn't mention if you recently had the air conditioner recharged, but if you did, another possibility is that the system is overcharged and that's causing your problem.
Make sure the A/C system isn’t overcharged. (It only
holds 21-23 oz.. If the system was recharged, take it back to whoever did it and have them remove the refrigerant and recharge it with the right amount.

I'd try the above in that order--do the idle relearn first, then have the idle set to specs, if that doesn't cure the problem, check, clean or replace the IAC valve and last but still a possibility is to have the AC system serviced and charged with the correct amount of refrigerant

hope that helps

Answer 2

There is a idle compensator that kicks in whenever the A/C is on and pumps a little bit more fuel in to counteract the load placed on the motor. This is more than likely what is wrong.

Answer 3

you probably need to idle it up.