89 4runner 3.0 V-6, manual trans with 155k, k&m airfilter
On cold (single digit to below 0 )start up accels to 3000 to 4000 rpms(guess no tach) can not bring down with accelerator pedal increases in rpms when you pat the pedal. As the engine warms the engine will step down in rpms and after 5 mins, back to its normal idle.
Here what I have done : Cleaned the throttle body took tooth brush and solvent and cleaned throughly. Checked all vacuum lines for leaks. Checked the cold start injector (within specs) Checked the cold start timer switch (within specs).Checked timing(within specs) Checked the dashpot.
Need input from you guys as this v-6 can't stay together with cold starts and 4000 rpm Idle for 5 minutes
thanks in advance

 

Mine was doing that for a bit when my thermostat was going out, revving up to 3000 though. Replaced my thermostat/coolant and it seemed to fix the problem. I'm not too mechanically knowledgeable though so...

 

Since it sounds like you have confidently gone through all of the cold-start electronics, and ruled out vacuum leaks, I would look to the AFM (air flow meter).

 

I'd check to make sure its really idling that high... Otherwise, that sounds normal to me. Its supposed to idle pretty high. Even with the IACV open all the way, I think its still engineered not to make it idle that high (3000 rpm).