Idle Speed Adjustment

PROCEDURE

Bosch Pump Manufactured Before September 1985

PROCEDURE 1. Warm up the engine. Oil temperature must be 50–70 °C.

2. Switch off all electrical consumers (headlights, radio, etc.). Make sure the starting device control knob is not pulled out. 3. On vehicles with automatic transmission, move the selector lever to position "P" and apply the parking brake. 4. Connect a diagnostic tachometer to alternator terminal "W" (indicated by the arrow in fig. Alternator Terminal "W"). 5. Adjust the idle speed using screw 6 (see fig. Bosch Fuel Pump Control Linkage) to 850±100 min-1 (850±30 min-1 for engines with a catalytic converter). 6. Secure screw 6 with paint. Bosch Pump Manufactured From September 1985

Bosch Fuel Pump Manufactured From September 1985 1 – idle speed adjustment nut; 2 – screw used for idle speed adjustment before September 1985; 3 – minimum engine speed limiting screw; 4 – engine speed limiting screw

Since September 1985, the idle speed adjustment has changed. For this reason, do not change the position of the screw that was used to adjust the idle speed before September 1985. PROCEDURE 1. Warm up the engine. Engine oil temperature must be not lower than 80° C. 2. Switch off all electrical consumers (headlights, radio, etc.). 3. Connect a diagnostic tachometer to terminal "W" of the alternator (shown by the arrow in the figure Alternator terminal "W"). 4. Briefly increase engine speed to 2000 min-1 several times. 5. Check the idle speed on the tachometer. It must be 850±30 min-1. If the speed differs from the specified value, adjust it with nut 1. Turning the nut clockwise increases the idle speed; turning it counterclockwise decreases the idle speed.

CAV fuel injection pump

Idle speed adjustment on the CAV fuel injection pump 1 – locknut; 2 – idle speed adjusting bolt; 3 – lever stop

PROCEDURE 1. Warm up the engine. Engine oil temperature must be not lower than 80° C. The starting device linkage must not be extended. 2. Switch off all electrical consumers (headlights, radio, etc.). 3. Connect a diagnostic tachometer to terminal "W" of the alternator (shown by the arrow in the figure Alternator terminal "W"). 4. Briefly increase engine speed to 2000 min-1 several times. 5. Loosen locknut 1 and turn adjusting bolt 2 to set the idle speed within 850±100 min-1.