This depends on the engine type.
The most common engine series in the Z3 is the 6 cylinder engines with dual VANOS. They have two camshaft position sensors located on the upper front of the engine. While the sensors are (barely) visible from above if you know where to look, they are much more easily located with a small mirror.
It's common for the original exhaust camshaft sensor to fail, and that's almost certainly the reason for this question. A replacement aftermarket sensor is about $40, while a BMW branded part is about $110. A new o-ring (under $1) is good idea. This sensor takes only about three minutes to replace. You'll need a 5mm hex key to remove the single screw holding the sensor clamp. Unclip the electrical connector, unscrew the clamp, pull the sensor straight out, and reverse the steps to install.
Located next to the crankshaft pulley
The 2001 BMW 325 crankshaft position sensor can be found on the back of the engine. The position sensor will be near the bottom of the rear engine cover.
The crankshaft position sensor is located at the driver's side bell housing. There are two sensors exactly alike being held with an Allen bolt. The one sensor closest to the front of the car is the speed sensor and the one closest to the rear of the car is the crankshaft position sensor. Hope that helps...
The crankshaft position sensor on this car is at the front of the motor on the passenger side. It is forward of the water pump inlet on a little mount. The toothed wheel it monitors is attached to the crankshaft behind the pulleys.
if you are facing the engine it will be on the left upperside of the crank pully, on a target wheel. is it hard to remove and replace
The 1996 BMW 328 camshaft position sensor is located on the front of the cylinder head. The camshaft position sensor should be labeled as such.
Its at the backside of the engine..look in the area of were the starter is.you will find it there
we cannot locate the crankshaft sensor for our 316 BMW petrol manual
It's on the drivers side of the engine, against the trans, under the starter. It usually has a 4 pin connector on it and the connector is facing the front of the vehicle.
It gauges the revs of the crankshaft (thats the rpm you see on your speedometer)
It is on the n/s of the engine just below the starter motor. It's a real hassle to get to. I am trying to do one at work at the moment. If I take out the starter I might be able to get at it.
The sensor is located at the front of the engine near the oil filter housing. To the left of the housing. 2.5 Z3