Volkswagen AMM Up for sale is a Good working Bosch Volkswagen 4 cyl AMM. This fits many 8 valve VW's from 84-93 as well as some other cars - Ford Escorts for example. Be sure to check the part number off your original to be 100%25 sure. These units are extremely expensive to buy a proper factory Bosch unit!Unit is used from a collision salvage car and is in good working condition. Flap works freely output signal looks good. I will warranty it for 30 days after purchase. I bad AMM can cause a lean running condition, loopy idle, no start, runs but has no power, random stalling, excess smoke, pinging, or any other strange running conditions. This is CHEAP compared to new or rebuilt, even at wholesale prices! As with all these flaper type Bosch air flow meters, you may need to do the basic setting adjustment (controlled by the tension screw) in order to dial this in properly for your car. See your cars service manual.