Low idle

I have a 1999 prerunner with 145,000 miles. When cold it will crank and idle around 800 rpms. After driving 30 miles or so it will not idle. If you remove your foot from the gas pedal it will go dead. I cleaned the throttle body and mass air and now it will idle at 200 rpm when hot. Any thoughts?? These parts are high and I don't want to start just throwing parts on it.

 

No engine light-It has a V6, that's about all I know. It's a 99 with auto.

 

Since it is a V6, when cold, it should run at just over 1000 RPM's. Closer to 1200. If it is already idling at 800 cold then it is probably dropping the 500 RPM's after it warms up. Try to adjust your throttle with the set screw and see if it will idle after doing that.

 

I would almost say seafoam it and put some new spark plugs in it. Mine was idling over 1000 rpm's when cold but when it got hot it would idle very rough around probably 500 or so and sometimes it would die.

I put new plugs in and seafoamed the intake, oil, and gas. It seems to have cured my problems and it only cost me around 20 or 20 bucks!

 

I cleaned the Mass air and sprayed in intake and put a can of seafoam in the gas. It will idle at 1000-1200 cold and 200-400 hot but it seems to getting better. Today it ran around 1200 cold and 1000 hot. I appreciate your advice. It is not giving a check engine.