I've got a 90 4Runner, V6, Auto, and lately it's been dying at stoplights and such.

It idles way too low (~300-400 according to the tach, I don't even know if that's possible) and is in high rev "warm up mode" for way too long after start up.

I thought it was supposed to idle somewhere around 800 rpm.

I had some work done on it and the mechanics found a fuel leak, a vacuum solenoid problem, worn timing chain, and some other good stuff to make it run as bad as it did.

I think the last thing that could be wrong with it is the TPS...I'm thinking about taking it off and cleaning it up like this. Does this seem like a good diagnosis? Would it be worth the time? Thanks.

 

It is supposed to idle at 800rpm. So, you're right.

It's possible you have more than one thing going on, but I'd look at the auxiliary air valve first. That controls the fast idle during warm up....which you are apparently having problems with.

There's a test in the '93 FSM that you can run. It should apply to your throttle body design, though. PG- 239 under air valve inspection.

http://personal.utulsa.edu/~nathan-b...93throttle.pdf

Wouldn't hurt to clean the TB, either....if it's never been done. That's cured a lot of idle ailments for people.

Cleaning and testing anything is never really a bad idea. Unless, you do it wrong, of course. So, the TPS would be worth the time. Might even be part of your problem.

 

Something else to possibly look for are any loose grounds or connections on / around the ignitor / coil and distributor.

 

Thanks for the advice. I'll take off the throttle body and clean'er up real good later this weekend. And check out the wiring and stuff.