Matt300ZXT

iTrader: (2)

It's not technically about an ES300, but a Toyota Avalon that uses the same engine, so I figured you guys would have a good idea as to what's going on.

My gf has a 96 that has a high idle problem. When she first starts the car, it idles at about 2000 RPM and when she drops it into gear, it idles around 1500 when in drive but stopped at a light or whatever. She says when the car warms up, it'll drop down to just below 1000 when stopped at a light, so still a little high but not as bad as when it's cold.

She took it to someone to have them look at it, some mechanic friend of hers I guess, and he says he thinks it's the throttle position sensor, but she said he didn't hook it up to any sort of code reader or anything.

So my question is, to you mid 90s ES300 guys, if you've had any similar problems, what did it turn out to be? She lives across town and my car is in the paint shop right now so I can't exactly drive over there with my ohm meter and check out the resistance across the terminals, but if I have a definite yes that the TPS is the problem, then I can hook up the ohm meter and start checking it out and adjusting or cleaning it when I have her bring it by here.

GS4_Fiend

iTrader: (22)

IACV passages clogged or defective. Common problem.

Matt300ZXT

iTrader: (2)

That's kinda what I was figuring from just the way other engines of mine have worked. I'll check into a cleaning procedure for that. Thanks!

Matt300ZXT

iTrader: (2)

Update....cleaned the IACV valve, soaked the hell out of it with throttle body cleaner and moved the little switch back and forth until the fluid ran out of the bottom of the valve about as clear as when it was sprayed in. I also replaced the PCV valve and grommet for maintenance reasons.

Hours later when it had cooled outside and the engine was definitely cold, she fired it up and still idled at 2k. Before it had a chance to warm up she thew it in gear and it dropped right down to just above 1k and she put it back in park and it immediately shot back up to 2k. Stayed there for a couple seconds then dropped down to 1400-1500 and stayed there until she left.

LeX2K

Your next step should be to look for vacuum leaks. A temperature sensor may also be at fault.

Hayk

iTrader: (1)

Try cleaning your MAF sensor. Otherwise, maybe somebody messed with the throttle cable. You could try to use an OBD2 scanner or a resistance meter to find out the Throttle Input(percentage) at idle.

Steelfan

I take it it isn't throwing any codes. Have you hooked it up to a scanner? Might want to run by an Autozone or Advance and borrow their scanner just to see.

My 2000 was doing something similar but it would pulsate at a stoplight and the idle was high. I was throwing codes though and had to replace both A/F sensors and that fixed it.

PS - anyone know what "normal" idle is for the 2000 ES300? I am running about 800 rpm, I believe.

hypervish

750 rpm is normal.

SC400slide

iTrader: (11)

^Definitely check the throttle cable...also since it is intermittent it might be the TPS at fault. And also clean the MAF like MrBooby suggested.

Matt300ZXT

iTrader: (2)

Does anyone have a walkthrough on checking the TPS? I checked and only found something on Auto Zone's page about testing it but it involves applying vacuum to it and checking resistances, but I don't really have any tool for applying vacuum.