Check your T.P.S. This is easily done with a meter to see if there are any "dead spots" in the TPS's resistance curve.

If it checks out good, do the idle air/TPS Voltage checks/adjustments. If you cycle the throttle from idle to full while monitoring TPS voltage it's another good verification of TPS linearity.

I don't have the link handy at work but do a keyword search on "TPS" or "IAC" and you'll come up with good tips on doing the checks/adjustments. Or check at the www.s-series.org 60 deg V6 forum.

HTH...........ed

'90 Troop 3.4 LS
'89 Troop RS (Has Valve Issues, needs Counseling)
HI, I'm Ed and I'm a Trooper-holic!
Keep On Troopin'......