GamblySmurf

The idle on my 2001 XJ fluctuates. It runs at around 600, then clicks and runs at around 800 for a few seconds then back to 600 for a few seconds, and so on.

I bought it used and it has done this since I bought it. I had it tuned and a vacuum line was replaced as well, but it still does it.

Is this just normal?

bluj99

my 99 sport does this as well and it really ticks me off. I have 2 fans one is the raidiator and the other i belive is a engine block cooler. when I have any heat or ac on my rpm's fluctuate as well as a drop in bat volts. I think it has something to do with the nessary power to drve the motor for the heat and to turn the fan to keep the engine cool. I must also say that when my heat or ac is on, fluctation accurs about every 10-15 sec's untill i shut off the heat controler.

best regards
Mike.

stumper

normal operation, see "Electric fan acting wierd" on the other page. a/c is cycling in and out, normal.

NozzleHead71

I have a 00 sport, and I had the same problem. Check the battery first, if it's low, it will make your IAC (intake air control valve) reset, and not read well. If your battery is fine, take your throttle body off, easy enough with the 4 10mm bolts, and then to take the IAC off, you will need a size 20 star drive. Get some cleaner, I used MAF cleaner from shucks, since it's not harmful to plastics. Clean the whole damn thing, throttle body and everything. Make sure you do not twist the little arm of the IAC, or press it down, you'll have to buy a new one (about 112.00 OEM) It worked for me just fine. Hope this helps.