Jmiller10

High idle (1400 RPM) in park at normal operating temp. Symptoms are: cold start idle 1000 - 1100 RPM. As the engine warms, idle increases slowly to 1400 RPM. In gear at a stop engine idles at 1000 RPM. No check engine light. Bought 98 ES300 a couple of months ago (161k miles) and have replaced valve cover gaskets, spark plugs, wires, ignitors, water pump, timing belt, cam and crank seals, high pressure power steering hose and power steering return hose. Also replaced (not sure what its called) EVAP control vacuum rail (sits on top of the engine, above the ignitors). Bought this part used off a 2000 ES300. Have cleaned the throttle body and did a quick clean of the IACV (did not remove it). Can't find any vacuum leaks. Car runs fine, idle does not fluctuate and it does start right up. Any ideas before I consider taking it to the stealership?

ES300NZ

make sure the throttle cable is 'slack' or ... not tight.

check the timing, one tooth out 'might' cause this.

check the piping after the afm for cracks etc.

blow 'smoke, coloured air, powdered chalk + high pressure (30psi) air)' into the inlet system after the afm (requires airbox & afm to be removed and pipe sealed up) to see if any vaccum leaks show up.

lostape45

Was the idle high before you did all the repairs? Or was it like this when you bought it?

Jmiller10

Thanks ES300NZ. I'll check the things you mentioned and post what I find.

Jmiller10

Lostape45 - honestly i don't recall as I was more focused on the oil and power steering leaks I didn't get a chance to drive it that much before the repairs. I want to say it didn't idle that high before. The engine and interior are so quiet, my other car is an Integra, so I may not have noticed until now.

ES300NZ

I think you would have noticed the massive sudden jolt from neutral to drive, or drive to reverse, but if two purple midgets danced past breathing fire and riding pigs, you may have been so distracted that you didn't notice. :P

lostape45

Yeah when it idles that high, there's a huge jolt when shifting, I mean even if you have the brakes on. I'm wondering if your iacv is sticking, like the motor in it is worn out.

Jmiller10

UPDATE - High Idle fixed - Removed the IACV from the throttle body and found that the sleeve/valve was stuck. Cleaned it out following the steps in the video posted in the "--Idle Air Control Valve diy?" post and now idles fine. Thanks for all the help on this one guys - love saving money!

ES300NZ

thanks mint dude, good stuff.