So I have an 87 4runner 22re and its been great for the last year and a half or so. But no it has an odd problem that's been bugging me for the last month or so.

When I start it up it idle's great right around 1000rpm, but once I give it a little gas then it will idle at 1500 from then on out which causes it to jerk around a little bit at parking lot speeds due to it wanting to go a bit faster than 5 mph or so. I thought this might be something with the TPS because I've had problems with it before but have been unsure due to the second problem.

This is where I'm confused, when I'm driving everything seems to run pretty well but when I go to stop it goes back to the high idle until I apply the brakes. Once the brakes are on it surges between 1000 and 1500 rpm but once I take my foot off the brakes it goes back to idle around 1500.

Anyone heard of this or can point me in the direction of a solution? Any help would be appreciated.

 

Application of the brakes makes me think that you may have a vacuum leak.
You can test for vacuum leaks via a vacuum gauge or spraying a bit of carb cleaner on the lines and listening for changes in idle.

I would say timing chain but the brakes should not have any effect on the idle if this were the case.

Lastly, Possibly a dirty/malfunctioning IAC valve be very careful not to rotate the internals or you will be buying a new one. (ask me how I know)

 

*Sigh*

Your warm idle speed is set too high. Do a search on "surging idle" it's been covered several times.

 

well said junkers.