ok, so i adjusted my idle to where its supposed to be... 850rpm warm.. and last night i drove on the freeway, and then when it would idle it would idle at 1500rpm. so i start it this morning, its idling at damn near 2300rpm! i adjusted the idle again, and it stayed at 1000, then just suddenly died. so i have it set back so it will run. any ideas? the haynes manual doesnt say anything

 

i had kind of the same problem, it was like my Dashpot Diaphragm. and it located on the throttle on the engine, it like a little rod with a boot on it and it sits against your throttle, and mine was not going completely down and thats why it was idling so high, and there is like a little Airfilter. i took it apart and stuff and put it back together but it was still happening so i just got a spring and hook it onto my throttle so it pulls it back to idle.

In the Haynes Manual its on Page 6-23. hope this helps if your having the same problem.

 

in a nutshell summary like thing- what's all been done to your truck, checked, verified, replaced, etc.?