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Computers and Control Systems: Adjustments

1. Run engine until it reaches operating temperature. Ensure cold start cable is not pulled out. Turn all electrical accessories off.
2. Place engine RPM sensor adapter tool No. VW 1324 or equivalent, on cylinder head cover and connect to battery.
3. Install positive lead of tester tool No. VW 1367 or equivalent, to adapter tool No. VW 1324 or equivalent, and negative lead to ground.
4. If idle speed is not within specifications, adjust as follows:
a. Loosen idle adjusting screw locknut.
b. Adjust idle speed screw, turning clockwise to increase RPM or counterclockwise to decrease RPM.
c. Tighten locknut.