My 90 Auto Trackers idle is driving me nuts!  If I adjust the throtle and TPS so that it idles at anything under 1300 rpm it surges between 800 and 1200 rpm and sometimes dies.  If I turn the TPS clockwise the idle raises and it runs okay for the most part other than that the idle is too high.  I don't understand why when it idles under 1300 rpm it surges or dies.  This appears to be a common problem, but I haven't read any definite answer anywhere.  HELP

ive had this problem for a year now too. ive also heard that it could be coil. so after a year or so im finally going to break down and purchase the blaster 2 coil from msd and see if that helps if not its just one more thing off the list of culprets :-/

ive had this problem for a year now too. ive also heard that it could be coil. so after a year or so im finally going to break down and purchase the blaster 2 coil from msd and see if that helps if not its just one more thing off the list of culprets :-/

Please let me know if the coil solves your problem.  I have also read it could be the fuel filter.  I will try those two next.

well i will definently let you know i should have it installed by this weekend if not sometime during next week, i bought the high vibration msd coil with the cap that will hold the wire on tightly.

Don't move the TPS, it needs to be set at
a certain spot, now you need to reset it.

there is a screw on the back of the throttle
body (8V motor) that you can adjust the idle,
also the Mikuni TBI has a fast idle air bypass
that if it gets plugged (works from the coolant)
it will stick and let extra air in and raise idle, this
is the cap with 3 screws in it, and has a coolant
line running to it, it faces the front of the truck
on the left side bottom of the TB below the EGR
stuff.

WILDGOODY TO THE RESCUE .........MAN HE KNOWS HIS STUFF......   MATTY D.  

Do a thourough check of the manifold!! I had that problem myself.  Mines a 16valve..  there was a very very tiny crack... a tiny line... when the engine warmed up and expanded.. the crack disapeared.

It would through the oxygen sensor off.  sometimes i'ld try to start it and it would just die... would never start without a little gas to help.    now that its fixed  it works great again.  for me it got worse later on.  as i would drive it would lugg down big time... then i give it a little extra gas... it would jet so fast i thought i was getting pulled by a viper!