Don@STaSIS

Haven't had a chance to diagnose fully yet, but either the second idle switch in 3 months has gone out or the ISV's electrical side has gone kaput. Found when cold the car liked to not let off throttle 100% on decel, but once warm that stopped. Replaced the idle switch and throttle potentiometer with known good units about 3 months ago after the problem got much worse, letting off the throttle at all below 3k rpm the car would like to cruise on it's own, dangerous for snow driving as you have to use the brakes a bit more, and it makes shifting a nightmare as the rpm's hang. Problem solved with those two components. Yesterday problem comes back worse than before, decel above 4k normal, the second it hit 4k the car immeadiately went onto cruise, any shifting below 4k became near impossible as rpm's stayed put slowly creeping downwards. Popped the ISV plug out and found the situation gone, cleaned ISV (old style) and found it to be very clean, valve side functional and easily moved. Put ISV back in with no change, unplugged and turned the idle screw out a half a turn, idles at 9k rpm and doesn't threaten to stall at all, actually steadier than before. I am thinking it's probably the switch again, but since this motor doesn't have much more use coming it's way why bother fixing. Just curious if anyone has run with the ISV disconnected for a longer period of time.

Cheers,

QCRAZY

If you can get the car set to run right with the ISV unplugged you won't do any damage to anything.

Merkin

yup, btdt

Don@STaSIS

Found the car won't stay running when cold, so plug ISV in, let warm up, pull plug and go. Tonight at the garage, plug ISV in, start the car, idles fine for the first min, hop inside to get some stuff, spent a few min talking, go back out to hear the engine at 3k rpm. Coolant gauge approaching the TOO hot zone, oil at 90C and climbing, header GLOWING red, unplug ISV, heat on full blast, and drive. Geez the idle valve is jealous of the other 20 I guess