Everytime I start slowing down to come to a stop and put the car in neutral and start braking, the RPMS surge. they'll fall to where they should be initially, but then they'll surge to 1500-1650 and come down to 1100-1200 rpm then bounce back once more before eventually stabilizing.

Why would this be happening? I initially thought it was because of the cold weather but it was 75*F today and it still did it.

Any suggestions?

 

ISC motor could be on its way out.

 

I have this same problem. I think its a programming issue

 

ISC Motor? What's that?

I'm wondering if cleaning my MAF could help.

 

Idle speed control motor. Had the same problem in my DSM as well as other Evo owners here.

 

Where is that actual part? Is it the same as the Idle Air Control on the throttle body?

Thanks

 

Anyone?

 

Yes its the same

 

I also have this same problem if anyone has any other insight?

 

No more ideas/suggestions?

 

I'm also having real rich idle, around 10.9-12.0. Anyone have any ideas?

 

boost leak test, I recently developed idle surge, and discovered I have a big boost leak. I'll be fixing it and fixing my idle surge at the same time

 

I did a 25psi boost leak test (rather Zeus did ) and we found 2-3 very small leaks all of which we fixed.

I am really hoping it's not the Idle Air Control valve not on its way out, because that thing is $$$$$

 

The surging never happened when my iac went or was on it's way out, rather quite the opposite. The ix has a different stepping program for the iac to compensate for in between shifts if I remember correctly. I would speak to your tuner.

 

this happens to me in one situation everytime

going down my driveway in first gear...turn to back in my garage...put the car in neutral...stop...then reverse

while the car is in neutral the rpm go to about 1300 and come back down to 900

weirds me out