ISC stuck closed?

[emd645e3]

Another thread about my idle surge! YEAH!

Anyway, is it possible that my ISC is stuck closed if the engine stops surging when I take off the brake booster vacuum line and let it suck in air through the inlet? It seems like more air is better for the surge, and that it has to be caused by lack of air if more air helps.

 

[DoctorMofo]

Unplug the ISC and see if it helps otherwise test the isc with a volt meter and see if it is within spec.

http://dmtalon.v8eaters.com/ISC.html

 

[emd645e3]

I already checked it, and it is within spec. I just thought maybe my volt meter might be giving me the right readings and all the coils are fun, but the thing is just stuck closed or in some restrictive position? I'm going to take it off and check it again, but I'm just seeing if anyone thinks its possible?

 

[emd645e3]

Also, when I unplug my ISC and idle switch, shouldnt the RPMs stableize? Because they don't.

 

[kottyking]

With idle surge it can be a number of things. I replaced all my sensors and biss screw the whole 9 and it still didnt fix it. I replaced my whole throttle body/ and gaskets and it solved my problem. It's different for everybody though.

 

[emd645e3]

With idle surge it can be a number of things. I replaced all my sensors and biss screw the whole 9 and it still didnt fix it. I replaced my whole throttle body/ and gaskets and it solved my problem. It's different for everybody though.

Do you know what role the TPS could play in it? Because I was told by a mechanic I trust that if I disconnect the TPS, the idle should change somehow, but it didn't. I'm looking for a test procedure for the TPS, but is it possible that this might be part of the problem? Yes, it is very different for everybody. Its like a pheonomenon, so many possible causes for one simple problem.

 

[kottyking]

yea i unplugged mine and it didnt change. I'm not saying that it is the same for you but for me i just bought a used throttle body and replaced all the SEALS and it went away.

 

[DoctorMofo]

Do you have a datalogger? Make sure the TPS is at 10%. Do a boost leak test cause alot of the times leaks are form the throttle body seals. Also you can the the FIAV blocked off which 99% of the times solves the idle surge.