Anyone got a TDC Ignition crank sender for an 84' 533?

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Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

I got no spark and tested the small crankshaft sender that runs from the OBD port (8-yellow, 9-sheild, and 10-black) to the lower front block.
the sender fails test. its not the reference mark or speed sensor as those connect to the left bell housing of the transmission.
this one is located on front of the block and attaches by a collar to read when to park.
I can not find this part anywhere online. thank you in advance!
Mike W.
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Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Mike W. »

Attached to the lower timing cover reading off the crank balancer? That's not your problem, it's non functioning. It was originally designed to be used by dealers to check timing, but I'm not sure if it was even used when the cars were new and I'm sure even the dealers haven't had the tool anytime this century. There is a little diagnostic connector, that you can check a couple of things with, and even engage the starter with, but I wouldn't call it OBD as that's smog related. Unless you're looking to have a perfect original restoration, visually speaking, you don't need the part you're describing. It's not used for anything.
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

That is what I though but apparently this is call a TDC Ignition sensor and is required for the DME to know when to initiate the spark.
I don't know why it runs from the "diagnostic port" or "maintenance reset port" to the block.
the closest part I can find is E30 M3, E24 635CSi TDC Reference Sensor Genuine BMW T#: 19368 | Part#: 12521287784
same part but with a connector just like most other camshaft sensors- Just got back from BMW and they cannot give me a part number for my car/vin.
How do I take pictures of this part, where it connects to, and upload it to the forum?
Mike W.
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Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Mike W. »

Your car does not use that sensor. There are two of what I call flywheel sensors, formally known as the speed sensor, which counts flywheel teeth, and the reference sensor, which tells the ECU where TDC is, although actually is only used at start. Now, those are identical parts, but count different things and if the connectors get switched the car will not start or run. Unless you have a M1.3 conversion, which started in '88 and have a crank balancer that looks like a gear with one tooth missing, your car does not use the sensor at the front timing cover. Yes it came with it, but it does not use it.

Posting pics is easy, but they have to be hosted offsite, Imgur.com is probably the most popular. viewtopic.php?f=1&t=147488
Federico
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Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Federico »

Here's a pic from one of my older posts. Like Mike said, that sensor is only used for diagnostics.

Image
Image

You would plug the engine to the BMW diagno test machine and use it to set the timing on the distributor. Dunno why it would be fitted to a motronic car.
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

well back to the drawing board then. car cranks but no spark and no turning over... don't even sound like it is trying to turn over-it just cranks.
Sean335
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Joined: Jul 25, 2020 5:48 PM
Location: california

Update to: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

Thank you guys for your points and stopping me before I go panic purchasing a crankshaft sensor for the front of the engine!
After reading your threads I pulled and tested the pumps and put power to them and they both started. (are the pumps on an all or nothing situation?)
And then the car would not even crank so I brought battery, starter, and Alternator to the shop for testing and they all failed. I killed them trying to start the car and honestly they were on the way to the grave anyway. Now it has a refreshed battery and new starter and Alternator and the car cranks like a champ but no start. Sprayed starter fluid in the throttle body and it fires up, struggles as it putters out. So no fuel is getting to the engine.

I no longer hear the faint sound of (what I believe) the fuel pump turning on when I turn the key to on position.
ill jump the relay tomorrow and ill pull the pumps again, put battery power to them and see if they still turn on while removed from the car.
With these fuel parts, are they operating on an all or nothing situation? in other words, can the pumps turn on and still fail to pump fuel?
I really hope I don't need a new computer, jussayin.
am I on the right track guys?
Mike W.
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Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Mike W. »

There is no prime function to the fuel pumps so you would not hear them when you turn the key. Jumping the FP relay for testing is a good idea though.
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

No prime function. I put the multi-meter to the connectors to check voltage. the in-tank fuel sender (has a 3-tooth connector) reads approx 5 volts and 11.5 volts. But the pump connector (2-tooth) does not give me a voltage reading when I turn the car to the on position, and no reading when I crank the car. hmmm what now?

*two weeks ago, I pulled the in-tank fuel pump and powered it-it turned on*
Mike W.
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Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Mike W. »

Sean335 wrote: May 16, 2022 7:55 PM No prime function. I put the multi-meter to the connectors to check voltage. the in-tank fuel sender (has a 3-tooth connector) reads approx 5 volts and 11.5 volts.
Irrelevant.
But the pump connector (2-tooth) does not give me a voltage reading when I turn the car to the on position,
Nor should it
and no reading when I crank the car. hmmm what now?

*two weeks ago, I pulled the in-tank fuel pump and powered it-it turned on*
What's changed? Any chance the main relay got switched around? It's a unique relay, a bit unusual, looks like other 5 pin relays but isn't, but will plug into other 4 or 5 pin relay sockets. And will make you pull your hair out if it gets switched. Double, no, triple check it to make sure it's the right relay in the right place.

Longshot, it's not an A/T is it?
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

1984 533i manual transmission 5 speed
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

ill go play with the relays and see what happens.
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

No voltage reading at the pump connection.
I jumped the no. 1 relay (from top to bottom inboard side of the fuse box there is 4 with two tandem in the middle).
And turned the key to on and to crank while checking for voltage at the in-tank fuel pump.
ill try again tomorrow and google some images of what relay is what to be sure.
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Mike W. »

The relays aren't always in the same spot, so I identify they by the color of the wires going to them.
Sean335
Posts: 16
Joined: Jul 25, 2020 5:48 PM
Location: california

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Sean335 »

Thanks for that. The relays were not in the place where I read it should be. I went through some of your previous threads, Mike and saw where the fuel pump relay is fed by several wires, one-red and another green with violet. I found it, Jumped it and turned the key to crank the engine, while testing the in-tank fuel pump connection. No voltage reading on the pump connection; 5v and 11.5v on the level sender.
Mike W.
Posts: 25739
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Anyone got a TDC Ignition crank sender for an 84' 533?

Post by Mike W. »

Then go back to the relay base and check for voltage at the large wire there.
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