WTF idle RPM surges

[qbano65]

As of late my Gn has been having rpm surges at idle. About every 5 second or so the rpm's will go from about 750 to 1250 and then immediately back down. It's very annoying and has me concerned. Today I noticed that before it would surge I kept hearing a "click" noise. After inspecting under my hood I realized it was coming from the alternator. Whatever it is that is on the bottom wheel(pulley) of the altenator is what's making the clicking noise. When it is not spinning the rpm's are normal, then it clicks and starts spinning and the rpm's go up. I don't have any idea what's going on . Help me out guys!


Thanks in advance,
Carlos

 

[Jimn8or]

Any chance that this is the air conditioning compressor clutch cycling in and out? Maybe you are on defrost or have AC selected on the dash controls. It cycles when the selected temperature is attained...OR when it cannot be attained due to low Freon levels in your A/C system. This unit puts such a load on the engine that it has to speed up to maintain idle rpm and if it unclutches right after the signal to clutch [low freon] the engine will receive opposing idle rpm commands right after one another.
HTH
Jim

 

[qbano65]

Genius freakin genius, I went out to my car fired it up, turned the defrost off (cant remember why it was on, but it was)and it went right back to that idle I've come to know and love. Man I love this site. Muchos Gracias Jimn8or


Carlos