|
Ok, either the ISC is working, or it isn't.
Does the Idle Surge right after the car has started, or after it has been run?
Did it come on all of a sudden, or gradually?
If it surges right after you turn the car on, you most likely need a new TPS, if it surges only after it has run for a while, your ISC is either Fouled of going.
To clean the Throttle Body and ISC, you should remove the Throttle body and ISC, then spray them with carb cleaner untill all deposits are off of them (about 2 hours of work).
Your car is listed as a TSI. TSI equals Turbo, which means you have a Mass Air Flow Sensor (MAF or MAS). Only the 2g NT's have the MAP sensor, because they don't use a MAS. There ecu's adjust the fuel according to throttle position, manifold pressure, and the voltage coming from the o2 sensor. While 1g's and All Turbos adjust fuel by the amount of air entering the engine through the MAS, and the voltage coming from the o2 sensor.
If you have removed all of the honeycombs, or opened flow around the upper honeycomb (through the bottom) too much, it will cause this idle surge, because the engine is running lean (more air is getting in then the engine accounts for), and then the voltage at the o2 sensor is wrong and the ecu is scrambling to fix it. Giving you an eratic idle.
Let me know how things go.
xhypno
|