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isc not working

Brunoboy

Well-known member
Joined
Apr 25, 2008
Messages
2,880
Location
San Bruno,CA Home of SFO
So replaced the ISC after my last ecu blew a driver, I replaced the ecu and rewired the pump as some of you may remember, I have a bad idle surge now, and I adjusted the biss all the way in and still idles and fluctuates around 12-1600 rpms, The ISC I pulled out to see if it'd move with the key in the on posistion, and it doesnt, the isc doesnt move either, so Im wondering what else it could be?, Do you think the ECU is messed up still? I had it checked and he said it was ok, maybe he missed something?
-Shane
 

SouthCaliVR4

Well-known member
Joined
Jul 31, 2010
Messages
984
Location
North county San Diego
check the o-ring on the biss, clean all the conections & disco the battery turn the key on for thirty sec, turn key off reconect the battery. it's worth a shot, did you get a "new" isc or source a used one? is your closed throttle switch connected & working, other vac leaks?
 

Brunoboy

Well-known member
Joined
Apr 25, 2008
Messages
2,880
Location
San Bruno,CA Home of SFO
it didnt surge before the replacement of those items, the isc is from dsmisc.com or something, new or rebuilt, but yea, what do you mean disconnect the battery and all that? My isc o ring is new as well and biss o ring is new, the isc doesnt move at all when the key is in the ignition.
 

Massive vacuum leak? Have you checked for that? So the problem started before you replaced the ISC and ECU? Or is this a new problem that developed after? Just trying to clarify and get myself up to speed cause I missed earlier modifications issues etc.
 

So have you tried another known good ecu? Known good isc? check for vacuum leaks(carb clean), and put in a new o-ring on the isc.
 

Brunoboy

Well-known member
Joined
Apr 25, 2008
Messages
2,880
Location
San Bruno,CA Home of SFO
new oring, no other ecu, ima have the drivers looked at, and i had two isc
 
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