E12 Crank Position sensor

Post your E12 technical questions and comments here. Please, no off-topic posts.

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71911
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Joined: Sun Aug 06, 2017 10:48 am
Location: Madison, CT

E12 Crank Position sensor

Post by 71911 » Fri Aug 03, 2018 5:41 pm

My 1980 528i crank position sensor is unplugged and the 3 socket plug is just dangling from the 12" length of wire from the sensor. I can't find where it is supposed to get plugged in. The car starts, but runs very rough. Anyone have photos of what it is supposed to plug into? I assume there is some sort of receptacle on the top side of the engine somewhere near the intake, but just can't find it.
Thanks

71911
Posts: 2
Joined: Sun Aug 06, 2017 10:48 am
Location: Madison, CT

Re: E12 Crank Position sensor

Post by 71911 » Fri Aug 03, 2018 6:23 pm

OK, 1/2 the mystery resolved. My son also has an E12 ('79) so I asked him to track the sensor wire on his car. So, I know the wire, plug, and metal bracket the plug is mounted in sits on a stud on the valve cover, just underneath the air cleaner. But the crazy thing is, his isn't plugged into anything either! Is the sensor necessary?
Thanks

PatinaBeforePolish
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Joined: Sun Jan 18, 2015 1:22 pm
Location: Baltimore, Md.

Re: E12 Crank Position sensor

Post by PatinaBeforePolish » Sun Aug 05, 2018 6:05 pm

It’s a port for long forgotten test equipment. Not needed.
78 F150
79 528i
81 528i parts car
01 540i
86 944

janusz200
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Joined: Sat Oct 27, 2012 2:24 pm

Re: E12 Crank Position sensor

Post by janusz200 » Thu Jun 13, 2019 12:56 pm

Hi, today I've bought the plug for this service socket, looks nice in bay but I still don't know what is this socket for - what was possible to check with this? Anybody knows?

Being curious about it I've just found this thread. To answer 71911 question I attach the photo of thermostat housing of my E24 (1980 3,5 littre M90 engine) - maybe it's of help.
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maybeillbuyit
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Re: E12 Crank Position sensor

Post by maybeillbuyit » Thu Jun 13, 2019 1:42 pm

Interesting plug cover, I've never sen that on a car. Did you get that cover from BMW? I just tossed the one on my e12 when I did the thermostat etc. I assume the crank sensor on these cars was used in some simple diagnostic system BMW used before things got more advanced to the larger diagnostic port on e28s and late e24s. RPM, timing, maybe used in conjunction with a timing light etc. Probably didn't tell you much.
janusz200 I would suggest getting rid of that early bleeder screw as they can be a bitch to get loose if they seize vs the later 10mm nut version
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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CabbageFumes
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Re: E12 Crank Position sensor

Post by CabbageFumes » Sat Jun 15, 2019 12:25 am

maybeillbuyit wrote:
Thu Jun 13, 2019 1:42 pm
..the later 10mm nut version
8mm...
Fiver 12/73
Fiver 06/87
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Threer wagon 04/03

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maybeillbuyit
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Location: Vancouver BC

Re: E12 Crank Position sensor

Post by maybeillbuyit » Sat Jun 15, 2019 9:55 am

:oops: Right you are
1977 530i another project
1979 635csi Euro "project"
1987 635csi

janusz200
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Joined: Sat Oct 27, 2012 2:24 pm

Re: E12 Crank Position sensor

Post by janusz200 » Wed Jun 19, 2019 2:11 pm

Thanks for hint about bleeding screw. Changing the coolant last time I scaresly moved this screw and fortunatelly it never failed. You mean to machine new thread M8 in housing? Have You a photo of new screw?

I've bought this beatifull red cap at BMW. Small thing, 2 bucks and so much fun.

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Mike W.
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Re: E12 Crank Position sensor

Post by Mike W. » Wed Jun 19, 2019 3:06 pm

janusz200 wrote:
Wed Jun 19, 2019 2:11 pm
Thanks for hint about bleeding screw. Changing the coolant last time I scaresly moved this screw and fortunatelly it never failed. You mean to machine new thread M8 in housing? Have You a photo of new screw?

I've bought this beatifull red cap at BMW. Small thing, 2 bucks and so much fun.
Image
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

janusz200
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Re: E12 Crank Position sensor

Post by janusz200 » Sat Jun 22, 2019 10:14 am

Thank you

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