Adjusting the idle speed of the engine of the K-Jetronic system (BMW 5 Series E12)

The carbon monoxide (CO) content in the exhaust gases is regulated by screw 1 (see photo) with a hexagonal recess for a key, closed with a plug. The CO content is reduced by tightening screw 1 with the KOEP 6.35 device.

Note: Do not increase the crankshaft speed with the KDEP 6.35 key inserted into the screw, as this may bend the air flow meter pressure disc lever.

The idle crankshaft speed is adjusted by screw 2 of the idle mixture quantity. Turn screws 1 and 2 alternately until the CO content is less than 3% and the idle crankshaft speed is within 900±50 rpm.