Is this idle surge? i've tried everything

[winnipegguy2236]

OK so this is for a 91 eagle talon tsi FWD. Tried everything. Just finished changing the insulators on the feul injectors but it's back. What happens is it'll idle fine until it goes out on the road. Upon getting close to a stop sign the clutch goes in and the bark is pushed. The car begins to surge from around 2k rpms down to 800 rpms rapidly going up and down, until you come to a complete stop then it stays steady at 800 rpms. Could it be caused by the canadian tire PCV valve that was put in? would i really need the eagle one? Everything else has been checked for boost leak. Would a leak between the downpipe and the exhaust cause this? it's been months and everything has been replaced. Would using rad hoses for intercooler lines matter? Everything is stock besides the custom exhaust and o2 housing.
Thanks i've tried all the FAQs.

 

[andymoraitis]

Two key things to check are:

1. ISC - test this for proper voltage or simply replace it since the car is getting on in years.
2. FIAV (Fast Idle Air Valve).
3. MAF Plug - make sure this is tight and that there are no wires hanging loose or frayed.

You may want to replace the PCV with an OEM unit, but I think your problem is more directly linked to one of the above. While you're at it, make sure the ECU capacitors are OK (no rotten egg smell) and also check the BISS screw for idle adjustment. An exhaust may cause some late spooling characteristics or to run rich (depending on where it is) and the rad hoses on the IC shouldn't be a problem as long as they're not kinked up.

Let us know what you find.

Andy

 

[winnipegguy2236]

ISC was tested properly and replaced
FIAV was looked at but i'm going to maybe try the block off see if that helps
MAF plug was never checked but i'll give it a go.
ECU is fine i even bought the new capasitors and gave that a try and nothing. Damn so angry
would you think blocking off the FIAV and EGR have an effect?

 

[andymoraitis]

ISC was tested properly and replaced
FIAV was looked at but i'm going to maybe try the block off see if that helps
MAF plug was never checked but i'll give it a go.
ECU is fine i even bought the new capasitors and gave that a try and nothing. Damn so angry
would you think blocking off the FIAV and EGR have an effect?

I've heard of people solving this issue on the 1G's by blocking off the FIAV and EGR. Since I have a 2G, I've never tried it, but again, it's worked for a number of tuners before.

Here's a link to a tech article that may get you going in the right direction:

http://www.dsmtuners.com/forums/showthread.php?t=191137&highlight=idle+surge

I hope it works for you!

Andy