rough idle and a/c problems
#1
rough idle and a/c problems
I have a 99 civic DX that recently started idling in a surge-like fashion. This only happens when the a/c is on, and when I am parked, i.e. at a stoplight. It also is intermittent.
Since it only happens with the a/c on, it should be noted that my a/c only blows cool air when I am driving. If I stopped - no cold air. I had this problem with another car and found it to be my electric cooling fan motor, I am guessing it is something similar, but my experience with Hondas has been much less, but I want to figure this out.
Any help would be greatly appreciated.
Aaron
Since it only happens with the a/c on, it should be noted that my a/c only blows cool air when I am driving. If I stopped - no cold air. I had this problem with another car and found it to be my electric cooling fan motor, I am guessing it is something similar, but my experience with Hondas has been much less, but I want to figure this out.
Any help would be greatly appreciated.
Aaron
#2
#5
Yes this sounds like a problem with the condenser fan. When the fan does not work the condenser overheats and the condenser pressure rises to an abnormal level. That requires the compressor to work really hard and overload the engine. Then the A/C starts to cut on and off to protect itself from high pressure, giving a surging effect.
When you are driving, the motion of the car forces air through the condenser even without the fan working, so the A/C works normally.
Most cars have one or two fans that cool both the radiator and condenser, but the 1992 to 2000 Civics have completely separate radiators and condensers with a dedicated fan for each.
When you are driving, the motion of the car forces air through the condenser even without the fan working, so the A/C works normally.
Most cars have one or two fans that cool both the radiator and condenser, but the 1992 to 2000 Civics have completely separate radiators and condensers with a dedicated fan for each.
#8
I turned on the car, turned the a/c on full blast, the fan is not turning on. Is the next step the relay? how do I check it out? The fan will spin, by hand, freely - so I know the fan motor isn't seized up. The fuses, under the hood are fine too.
#9
here is the manuals for your car download it. it will explain everything.
http://hondatech.info/downloads/Auto/Manuals/Civic/
http://hondatech.info/downloads/Auto/Manuals/Civic/
#10
First check that the A/C ground wire is in place. I think it comes up from the wiring on the condenser fan and grounds to the radiator support.
Find the 2 relays near the condenser. One is for the compressor and one for the fan. Swap them. If now the fan works but the compressor doesn't, it's a bad relay.
Unplug the fan and use 2 wires to jumper it to a car battery (can be the one in your car). If it does not run the motor is bad.
Find the 2 relays near the condenser. One is for the compressor and one for the fan. Swap them. If now the fan works but the compressor doesn't, it's a bad relay.
Unplug the fan and use 2 wires to jumper it to a car battery (can be the one in your car). If it does not run the motor is bad.