The intermediate shaft is used only on the M20 engine. The shaft rotates in the cylinder block parallel to the crankshaft. It is driven by the timing belt and its only task is to rotate the oil pump.
1. Remove the timing belt (see section Repair work carried out without removing the engine from the vehicle).
2. With the belt removed, unscrew the bolt securing the toothed wheel to the intermediate shaft and the front cover bolts.
3. Remove the oil pump drive shaft (see Part Repair work carried out without removing the engine from the vehicle).
4. The shaft is held in the cylinder block by a plate with two bolts. Remove the bolts and pull the shaft forward out of the block.
5. Inspect the bearing surfaces of the shaft and the gear at the rear end that rotates the oil pump shaft for signs of abnormal wear. If the bearing surfaces in the cylinder block are worn, a mechanical workshop should be consulted.
(The text is based on materials from the website: bmwman)