Surging when cold just started

[volcomsnow245]

Hey guys my car just started to surge when I first start it after it's been sitting over night but it doesnt do it if i start it back up after its been run. I checked most of the stuff but the FIAV anyone have this problem and know how to fix it.

 

[boostedbill]

iv been have the same problem with my tsi. it has a 6 bolt swap and i cleaned out the iac and used a test light to test my tps swith and it ended up being the iac and i also grounded the intakemaifold to the fire wall. hope it helps

 

[92AWDHX40]

[email protected]


mine used to until i changed my isc.

 

[OMFGeofffff]

It is most likely the FIAV. It affects your idle when coolant is cold vs. warm. A lot of people have problems with the fiav so they just buy a block-off plate.

 

[troppo loungo]

I would go with FIAV as well.

 

[steve]

While it's clearly the extra air that the FIAV bypasses when cold that is pushing you into surging, it's not clear or necessary that the FIAV is bad. Try adjusting the BISS to spec and see if it still surges. Make sure your ISC is functioning correctly. If the BISS is too far out and the ISC is largely closed at normal temps you can see surging when cold.

 

[miguelmcv]

I would go with ISC,
If it is not working properly it will give some big headaches.
Test it and see if all coils are good.

I just changed two.
One had one coil bad, and the other was throwing 44 ohm on all four coils,,,, Lucky me, it didn't fry my ECU.

 

[bertrenolds]

IACV, or a boost leak. Do a leak down or pay $100 at autozaone for a new IACV.