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I got wett 1bar chip, since I put it in, everything is great, after a month, the problem is exists, the engine can't keep idle at the first start. Thanks for anyone can provided infomation.<br>

... a bad sensor or a vacuum leak. Previous model years of Audi's had problems with idle stabilization. If I remember correctly, two culprits need to be looked at: check all hoses to make certain there are no tears/cracks and all are connected or plugges at either end. Use the air conditioning controls to check for codes (see FAQ for instructions), or use the various tools or your dealer. If a sensor (i.e. throttle position, temperature, oxygen, air mass, etc.) is sending erratic data, this could cause the problem.<p>All above IMHO and is worth exactly what you paid.<p>AlexS