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It most certainly does matter and cannot be flipped.
 

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That sucks. So it remembers position then? Because it obviously reads the different metal lengths of the sprocket on the cam. So I would think it would only go off that.

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and the way you have it, it will be 180 degrees off
 

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It doesn't remember, it is a live position feedback. The irregular long and short "tooth" profile signals from the reluctor acting on sesnors are compared to the 6 degree spaced flywheel sensor signal to determine which crank revolution the engine is in for correct coil and injector operation at correct time. The variable cam timing function is using the cam position from sensors for regulating the oil pressure in the CVVT units (phasers) to get cams to desired positions.
 

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Discussion Starter · #6 ·
It doesn't remember, it is a live position feedback. The irregular long and short "tooth" profile signals from the reluctor acting on sesnors are compared to the 6 degree spaced flywheel sensor signal to determine which crank revolution the engine is in for correct coil and injector operation at correct time. The variable cam timing function is using the cam position from sensors for regulating the oil pressure in the CVVT units (phasers) to get cams to desired positions.
Ok that's what I'm saying. It only cares about the length of the tooth right? So as soon as you start the car it picks up on where it's at. Whether the magnet is up or down shouldn't matter.?

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The relative position is off. Perhaps an easy to understand analogy is to put a distributer cap on other way around. Yes it is still spinning, but firing wrong cylinder.
 

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That analogy does not apply.

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The ECM knows the position of camshaft relative to the crankshaft and other camshaft.
It knows the valve opening and closing points and calculates overlap which is an input to many maps and functions.
It calculates it based on which flank (four flanks) is passing through the sensor. If you put the sensor upside down, you’re telling the ECM cam is flipped 180 degrees and it tries to correct the position by adaptation. Maximum adjustment range for intake cam is roughly 50 camshaft degrees. +- 8 degrees is the diagnostic threshold before error is stored.

Only way to make this work is to turn the impulse wheel at the end of the cam by same amount as the sensor is turned. As it has slots to fit and secure behind the cam, you would have to file them off.

Good luck.
 

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Discussion Starter · #10 ·
The ECM knows the position of camshaft relative to the crankshaft and other camshaft.
It knows the valve opening and closing points and calculates overlap which is an input to many maps and functions.
It calculates it based on which flank (four flanks) is passing through the sensor. If you put the sensor upside down, you’re telling the ECM cam is flipped 180 degrees and it tries to correct the position by adaptation. Maximum adjustment range for intake cam is roughly 50 camshaft degrees. +- 8 degrees is the diagnostic threshold before error is stored.

Only way to make this work is to turn the impulse wheel at the end of the cam by same amount as the sensor is turned. As it has slots to fit and secure behind the cam, you would have to file them off.

Good luck.
I see what you're saying but that cam gear has different size teeth so it can move independently and its position is still known. It's not fixed to the rotation of the engine like a distributor.
The question is: does the mag pickup reset when you turn the car off? Obviously moving the sensor while running would throw its position off but each time you start the car does it wait for, say the big tooth, and the ecu is like ok here is where were at for timing now. Or does it assume the mag pickup is at 12 o'clock and start timing off that? I think the later would be a poor way to program an engine.

Is there any actually data on this?

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I see what you're saying but that cam gear has different size teeth so it can move independently and its position is still known. It's not fixed to the rotation of the engine like a distributor.
The question is: does the mag pickup reset when you turn the car off? Obviously moving the sensor while running would throw its position off but each time you start the car does it wait for, say the big tooth, and the ecu is like ok here is where were at for timing now. Or does it assume the mag pickup is at 12 o'clock and start timing off that? I think the later would be a poor way to program an engine.

Is there any actually data on this?

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It is fixed to the rotation of the engine. Cams do have a range where they can rotate independently yes, but they still turn along.
Nothing is “reset”. The cams are not actuated during cranking, but the positions are checked immediately. By that I mean ECM checks if reference postion (mechanical resting position) is correct.
Only thing stored in memory post engine turning off is crankshaft position. This helps to shorten the start up time as the crankshaft doesn’t have to do two revolutions to check crankshaft position. This was evident in older Volvos with M4.3 engine management. In M4.4 ECM cars the position is saved.
 

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I think there's only one way to resolve this... Boostednbagged needs to flip the sensor and upload video of him starting and running the car. I'll get the popcorn.
 

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Discussion Starter · #13 ·
I think there's only one way to resolve this... Boostednbagged needs to flip the sensor and upload video of him starting and running the car. I'll get the popcorn.
I would've already done it if I could start my car lol.

And worst case the ecm would just run a default map; nothing would blow up

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There's only a small magentic type pickup inside the round case. Maybe 3d print or cnc a case with correct oreientation to mount the pick up into. Its a fairly simple part. Might get a bit pricey, but you seem all in already. Haha.

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Discussion Starter · #19 ·
There's only a small magentic type pickup inside the round case. Maybe 3d print or cnc a case with correct oreientation to mount the pick up into. Its a fairly simple part. Might get a bit pricey, but you seem all in already. Haha.

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3D Print that's a good idea...

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Ideally 3d scan an oem one, then just rotate the mounting holes in CAD to desired location. And ypu could add some embellishments to the case, a nice logo or something.

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