Crank pulley dowel

Post Mon Feb 13, 2012 4:14 pm

I have a pre-facelift 325i cab that refuses to start. I have looked at a few posts on here and have noticed that the dowl pin that is supposed to sit in the crank pulley to trigger the crank sensor is missing. Is there any way I can get this pin? I have checked real oem and cant even find it on the drawings! Thanks

Post Mon Feb 13, 2012 5:32 pm

I think you've got mixed up.

The dowel pin that goes AWOL is not on the pulley, it's on the flywheel in the gearbox bell casing, and that is only on "real" pre-facelifts.

Your cab, despite having chrome bumpers, is probably only doing an impression of a pre-facelift (understandable) and really will have Motronic 1.1/ 1.3 with a toothed flywheel mounted next to the pulley.

What year is you car?

Post Mon Feb 13, 2012 6:52 pm

My cab was built 07/1986. It looks like it has a cps on top of the crank pulley. The pulley itself is completely smooth apart from a small hole about 2-3mm in diameter and 5mm deep. Im guessing it may be the older L-jetronic system? The Car was running fine 10 days ago but now will not start!

Post Mon Feb 13, 2012 6:53 pm

also the ecu number ends in 073

Post Mon Feb 13, 2012 7:05 pm

Do you mean this ?

Post Mon Feb 13, 2012 7:17 pm

jimjim wrote:My cab was built 07/1986. It looks like it has a cps on top of the crank pulley. The pulley itself is completely smooth apart from a small hole about 2-3mm in diameter and 5mm deep. Im guessing it may be the older L-jetronic system? The Car was running fine 10 days ago but now will not start!

Sounds like you have M1.0, some very early cabs did have this. There is no CPS on the front pulley, it is on the flywheel like in Petes pic.

If you have a CPS on the front pulley it would look like this;

This is the pulley it would have, not the smooth one you describe;

If someone local has an ECU they can lend you that'd be the first think i'd try.

Post Mon Feb 13, 2012 7:19 pm

jimjim wrote:My cab was built 07/1986. It looks like it has a cps on top of the crank pulley. The pulley itself is completely smooth apart from a small hole about 2-3mm in diameter and 5mm deep. Im guessing it may be the older L-jetronic system? The Car was running fine 10 days ago but now will not start!

Sounds like you have M1.0, some very early cabs did have this. There is no CPS on the front pulley, it is on the flywheel like in Petes pic.

If you have a CPS on the front pulley it would look like this;

This is the pulley it would have, not the smooth one you describe;

If someone local has an ECU they can lend you that'd be the first think i'd try.

Post Mon Feb 13, 2012 8:47 pm

073 ECU is Motronic 1.0 so it is a real pre !!!

The "CPS" you can see against your smooth pulley is nothing more than a (very basic) diagnostics sensor and does nothing for or against the running or not of the engine.

If you have lost the dowel (possible) then you need to be looking on the flywheel in the gearbox bellmouth.

Or it could be the ECU as kedge says... but we're just guessing without more info.

Post Mon Feb 13, 2012 9:09 pm

Info on the CPS, including locations for both Motronic and Jetronic, are in the Wiki:

http://www.e30zone.net/e30zonewiki/inde ... ion_Sensor