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Re: Random idle issue question (Mk1Power)

Sounds like an O2 sensor. When I got my 16v rocco, my car did the same thing, drove me nutz. I cleaned the idle stabilizer with carb cleaner, replaced the plugs, wired, cap, rotor all kinds of normal tune up stuff.
Eventually thought maybe the fuel/air mix was off, read about how to set it and when I hooked the voltmeter up, I found a bad setting which lead to a bad O2 sensor. I replaced the sensor and some ground wires and the problem went away. Untill I cracked the downpipe due to bad motor mounts and now the O2 doesn't get enough exhaust gases to make it work right and I have light hunting at first start.
If you haven't replaced the O2 sensor, then chances are it's original and way past it's end of life. They arn't cheap, but you can get one at http://www.oxygensensors.com for a bit less price. Don't fool with the generic ones that don't come with the full pigtail/plug. Those are cheap, but you will have to solder the proper connection on. If you're real good at that, then go for it. If you can't solder, then pay the extra and get the full sensor and plug.
Just incase you don't know, the O2 sensor is under the car, and screws into the catalitic converter. It's a pain to get at, but can be done. The wiring goes up and behind the intake manafold. There are 2 seperate connections (electrical) to the sensor.
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