I am having problems with my RX300, year 2000. Engine Idles at about 1 then jumps to amost 2 and back down to 1 every 7 seconds. I tried changing idle air control valve / catalyc converter / 02 sensors. But that did not solve problem. Did this happen to any one else and what was the fix. Please help

 

Do you have any CEL's? Rather than throw parts at it, let's try to get down to the source of the problem.

I suppose you cleaned the throttle body while you were in there? Did you unplug the battery to reset the ECU?

Does this happen on a cold idle? Or, will it happen after the car is warmed up as well?

Any vacuum leaks?

 

cleaned Throttle Body and also replugged battery.
Thx for the quick reply

 

have you pulled any codes,if so what are they,you can have the code pulled at autozone or advanced autoparts for free

 

you verified you could turn the IACV without much resistance?? i know you replaced it but maybe the assembly needs cleaned.

 

If he just replaced it, certainly it wouldn't need cleaning already. Pull to the side of the road and clean it every couple of miles? I don't think so.

 

Did you ACTUALLY throw all those NEW parts at it? Seems like it would have been cheaper to at least pay to have it professionally diagnosed, since those are not cheap parts. I do hope you used OEM parts. Back when '47 chevy's were the thing, I think aftermarket parts were fine, I generally wouldn't trust most aftermarket parts on todays highly complicated and sophisticated cars at all. Some may work fine, some may not, and then you've got a nightmare, unless you don't consider chasing your tail a nightmare. That's a strange problem and with an '00 still having mechanical throttle, that makes the problem even more puzzling.

Edit: You should be able to remove the 2 screws that hold the black "bake-a-lite" (sp?) piece that contains the magnetic fields and actually run it and turn that little round piece on the end of the air intake vane and see what you can do with the idle. See if it turns free and if you can simulate the same idle fluctuations that it does with that on. You don't have to take anything else apart to do that. You should even be able to take the screws out and turn the part with it still on and connected. There is a small adjustment available with the screws in, but with them out, you should be able to turn it unlimited, to see if that makes any difference.

 

Did you change the air filter before all this started? Perhaps you forgot to replace a vaccum line? Also did you clean the MAF???

 

Thanx for all the help. I will put it on machine and get codes. All parts were new, but not bought from Lexus.