Tonight I cleaned out the IACV when my 2000 RX started to idle a little sluggishly. I removed the valve from the throttle body and cleaned it thoroughly and assembled it back together exactly the way it came apart, but now the engine is laboring when in gear and the check engine light is flashing when I accelerate. I'll take it in when the shop can fit me in. But do the experts on this forum have any idea what might have gone wrong?

Thanks in advance.

 

Well a flashing check engine light might not be symptomatic of a bad IACV, but rather a misfire. I know about 4 years ago when I had my last misfire (back in Mexico) that was exactly what occurred and luckily I was able to modify a Toyota Camry coil to fit until I could get one that was precisely the same for the RX300 (they can work, but there are slight differences). I am pretty sure when they read the OBD2 code it's going to say something like P030X with the X being the cylinder number. If you are looking at the engine from the front of the vehicle, the ignition coils behind the engine block will be numbered 1, 3, 5, so if you had P0301 that would mean the passenger side rear coil, a P0303 would be just to the right of it. The front coils (underneath the engine cover with the little Lexus L) are numbered 2, 4, 6 from passenger side to driver's side. That's why I always recommend getting a cheap code reader (look on Amazon or even at Costco as they have some under $40 and you don't even need the new CAN protocol to read the codes on these vehicles

The coils are held in by a single 10mm bolt and go on top of the spark plug (you won't need to deal with the spark plugs, just the ignition coil). I highly recommend sticking with the original Denso ignition coils and not going for a cheaper aftermarket (same goes with a MAF sensor or the A/F sensors), but I am not original parts on everything and I'd give you my opinion depending on the problem.

 

For emission [fuel, air and spark] related stuff, let the OBDII do the diagnosis. There is no guaranty that the diagnosis will be complete and accurate, but it will give you pointers.

If the RX is dirveable, get it read. DIYers should have the reader as a tool.

Salim

 

Thanks to Lexmex and Salim!

 

if it comes down to it ... i have a spare brand new IACV available..... pm me if you need one....