Help! '93 Es300 Iacv Question

[Olnick]

Hi all. I know next to nothing about Lexus (other than they are beautiful, well-respected vehicles!) Am trying to help a family friend with the infamous "won't idle" problem.

It's a '93 ES300 with, according to the owner's manual, a 1MZ-FE engine. Studied everything I could find here about IACV cleaning. But this morning when I dove under her hood I found a totally different IACV unit than expected.

The IACV is NOT the rotating cylinder type that mounts under the throttle body. It is a "worm-rod driven plunger" unit that mounts on the side of the TB close to the firewall.

I removed it and cleaned it up (it didn't really look too dirty!) and in the process I depressed the plunger. Put it back together, test started the car and it idled perfectly. So I shut it off, cleaned up under the hood and got ready to take it for a test drive.

When I started it again there was absolutely NO idle. It wouldn't even fire up unless I kept my foot on the gas.

Any suggestions about this type of IACV? Is the "stepper motor" bad? Anyone know what pins I might check in the electrical connector? Could it be as simple as a blown fuse?

Appreciate any input--our friend has already spent a lot of money trying to make this car dependable and safe and I really want to help her out.

[Olnick]

A follow-up:

1) After more research, this is obviously the 3VZ-FE engine. Looking at replacement IACVs on the web, that's clearly the model that matched.

2) The owner's manual was not original, it was obtained for her by the dealership. The cover says "1993 ES300" but the spec page lists the engine as a "1MZ-FE." Go figure!

3) None of this matters anymore! Our friend went and started the car later this afternoon and it idled, rough at first then it smoothed out. She even came by the house so I could take it for a spin.

It's running as smooth as a . . . Lexus!

Thanks for your interest. Aloha.