Engine click sound followed by RPM's dip to almost stall.

CFL-ERDAVID

MEMBER
FORD EXPLORER

1997 Ford Explorer SOHC 3.0 V6 w/ 195000 miles. Run's well except recently I noticed that at idle I hear a loud click followed by a dip in rpm's to the point of almost stalling. Then it comes back up and about 5 seconds later it does it again. I held engine rpm's at 2500 in my driveway to see if it did it at higher rpm's and it did but click was faint and rpm dip not so drastic. Does anyone know what that is?
One thing to add. It seems to only happen when I turn my heat on. I turned the heat off yesterday afternoon and it stopped doing it.
Please and thanks.
D

1 Reply

CFL-ERDAVID

MEMBER
2 POSTS

Hi,
It runs well. Starts well. Hot or cold. It really sounds like my AC unit motor is trying to kick on. Even though I'm trying to use heat. I can't switch from hot to cold air. I think that motor/switch just doesn't work anymore. So heat is on all the time. I can turn the other dial to off though or I can set it to lower vent, upper/lower vent, AC, defrost, etc. When I set that dial to anything but off or lower only vent then that click sound starts with the rpm dip. That's the best way I can discribe what its doing. The same way an ac unit sounds when its kicking on. I think I might disconnect the ac unit and see if that helps. Since it doesnt work anyway in the sense that there is no cold air. Motor works though.
Does that make sense?

Thanks.D