FrankieP

Replaced the alternator yesterday. The replacement was relatively simple. When I put everything back together and started the car, I noticed a couple of things: I noticed that the car was running quiet because the idle was around 500rpm. That bothered me because it seemed really low. I checked the forums and was told that the ECM needed to figure out where the idle needed to be... It is still around 650 but I think it's fine now. Drove about 100 miles today and had no issues.

Next there was a clicking sound under the hood. Sounded like a solenoid attempting to engage about every 2-3 seconds. I'm not sure where it's coming from - it is near the fan motor and alternator. I think... When I increased rpm, the clicking went away. Since the battery was really low, I thought there simply wasn't enough voltage to actuate some solenoid. After driving several miles today, I went into my office for about an hour. When I came out, I started the car and heard the clicking again. More rpm and clicking goes away... The outside air temperature was between 108-110 today and the AC was on. When the AC goes on is the cooling fan supposed to come on? Even if the car is relatively cool? I refer back to the lower idle. I mentioned that the car seemed quiet. When the AC compressor is engaged, the cooling fan is not running. The engine temp is where it always is. Just curious if anyone might know what the clicking sound is under the hood. It sounds a little like the AC clutch when it engages... Besides that everything is normal - output from alternator is in at 12.7V and there is good ground on the alt. Testing the housing I get about 0.3V and 0.5V with a load. I think everything related to the alt is working fine.

If anyone has any ideas or advice, I'd be much obliged! No apparent issues other than noise. I hate noises.

HomerJay

What is the voltage at the battery with the engine on? 12.7 volts is too low, should be in the range of 13.5 - 14.3 volts (approx)

FrankieP

Sorry. Fat fingers... 13.7 volts.

speedkar9

Cooling fans should be running when the A/C clutch is engaged. Clicking could be the compressor trying to turn on and off due to low refrigerant, or the fan relays. Check the fans to make sure they are working properly and nothing is lodged in them or disconnected.

Does the A/C cool the vehicle sufficiently at idle?

FrankieP

Thank you for your response. The compressor engages and cools the car at idle. I checked the refrigerant and the pressure seems good - living in this God-forsaken desert, I always make sure my A/C is healthy! Cooling fan doesn't always come on when the compressor is engaged though. They spin freely and there is no visible obstruction... I'll check the fan relays. I appreciate your input.