surging 91 200q

["Mike Miller (Volt Comp)" <a-mikemi@microsoft.com>]

While helping a fellow list member troubleshoot a problem on his car by
swapping parts (fuel pump relay) betwixt the two, a problem has surfaced
on mine. Attempting to dump the diagnostic fault codes (3B engine) by
putting the fuse in the fuel pump relay for 4 seconds+ then removing it
had no effect. The diagnostic mode never started. We retried this with
ignition off, on and car running. After trying it with the car running,
the check engine light is always on. Putting the original relay back in
had no effect. It occasionally ( 5 - 10 minutes) "blinks" off
(momentarily dims - *not* in diag mode) and comes right back on. Also,
while slowly depresing the accelerator pedal and letting the rpms rise
to  about 1300, the rpms hold at 1300 for just a tad more pedal, then
rise to about 1500 and start cycling (2-3 seconds) between 1000 and 1500
rpms while holding the throttle steady. Applying more throttle and the
rpms increase as they should. Unplugging the idle valve and the ISV with
the car running has no effect on the problem nor the way the car runs.
Anyone have any ideas?

mike miller
91 200q