I have a 97 150 w 180,000 miles and i pulled in the driveway the other day and heard a clicking noise...popped the hood and noticed the compressor was engaging disengaging rapidly, like every second. It stopped the noise the next day at idle, but when I drive it, and usually at accelerating, the truck shudders, and wont stop unless I kill the a/c. (still does it a little, but not as bad as when the air is on) I am wondering if the compressor is going out, and will it lock up even if the air is off. I use this as a work truck and dont want a severed serpentine belt, a repair bill, and a towing charge. let alone deal with tools in my truck at the time of failure....inside the air works fine, the pressure was checked a few months ago, and is at the proper level, do I need to start searching for a new part now, so I dont have to deal with what I have read on FTE dealing w metal shavings everywhere?

 

so many views, but no responses? very suprised! I hit the front of the compresser w some WD, hoping that will help, seems ok so far...

 

Just because pressure was ok a few months ago does not mean its still ok. Have it checked to make sure you're not low on freon.

Just out of curiosity, is the Check Engine Light on?

 

gang, no response is normally due to conflicting data. I dont see how a compressor cutting in and out would cause the truck to vibrate. How about pulling the power cable off the compressor and driving the truck for a day. No vibration that day ? If so, then i guess your right, the compressor has a problem. Sometimes the air gap on the clutch is not right and the magnet will not hold the clutch closed. It might jump in and out... but i dont see that causing a vibration.

 

How many miles ago did you change your spark plugs.

 

alright, I will try and answer all the questions... My check engine light is not on, and for the most part the truck runs great. I doubt it is low on freon because the air runs very cold. I changed the plugs about 8,000 miles ago, it got a nice full tune up, and new coils.
I havent seen the compresser click like I did the other day. It was seriously engaging, disengaging rapidly. But it still shudders when I give it gas, say going 45 mph steady it shakes, like front to back...not side to side. It has a nice new set of pads, and freshly turned rotors on the front. When it shudders, my engine isnt hesitating(figured thered be a check light on) and the fan speed on the air doesnt change. Thats why i am baffled. I hope this isnt transmission related...last month I changed fluid and filter, and tranny worked nicely. Just find it weird that the shuddering im feeling almost disappears when I turn the air off...and I cant do 45 down the road while watching the compressor (when I first noticed, and seen the compressor doing what it was, when id hit the gas, it would start clicking more the harder I pressed on the pedal..but almost stopped when I let off) Sorry this was alot to type, but im trying to be as descriptive as I can. Thank you everyone for your input and questions