intermittent valvtronic issue

fooledyas · 09-05-2016, 11:15 AM

2011 328i n51

ok I got a service engine soon light last week code 2a32. eccentric sensor reference. I've been troubleshooting with ista+. it shows the sensor at 0 when requesting 225 degree. when I do the relearn valvetronic stops I can see the shaft move and the sensors shows a different angles. as I run the engine I can see these values changing. Then the engine bucks and sensor shows 0 and 225 again no chance as I rev the engine. if I watch the eccentric shaft as the car runs I see no movement. my question is do I have a sensor problem or a valvetronic issue. should the eccentric shaft stop moving when the sensor stops working. I have read that when the sensor stops working the intake butterfly controls airflow instead of the valvetronic sensor can anyone verify this. has anyone had a valvetronic sensor or motor with intermittent problems?. I'm not sure if I should be replacing the motor or the sensor.

hassmaschine · 09-05-2016, 11:21 AM

The sensor has failed and its in limp mode, the eccentric shaft moves to full open and it uses the throttle plate instead. Thats why it doesn't move.

rjahl · 09-05-2016, 11:22 AM

It's probably the sensor. The motor keeps bringing the eccentric cam to the default position when the two sensors don't agree with each other. Dual sensors integrated in the same sensor part.

You can test the VVT motor with INPA.

fooledyas · 09-05-2016, 02:12 PM

thank you that's what I though. I was confused because it worked sometimes. It's been my experience that sensors either work, work poorly or don't work.

rjahl · 09-05-2016, 04:21 PM

Quote:

Originally Posted by fooledyas

thank you that's what I though. I was confused because it worked sometimes. It's been my experience that sensors either work, work poorly or don't work.

Failed sensors are really common, at least on this forum.

I would still run it through INPA to be 100 percent sure.

If you are doing the work yourself, you could purchase both the motor and sensor. If you don't need the VVT motor, you can return it.

Get gaskets for both the valve cover and the VVT motor. Replace both even if your VVT motor is good.

fooledyas · 09-05-2016, 05:56 PM

Already ordered sensor and gaskets. When I get in I'll check the shaft bearings , if sensor doesn't solve then I'll pickup a motor. I deal with a lot of servo motors at work the almost never go , but the ones I work with aren't exposed to heat and weather.

09-05-2016, 11:15 AM	#1
fooledyas Private First Class 11 Rep 162 Posts Drives: 2011 z4 and 328i Join Date: Apr 2012 Location: 1175 iTrader: (0)	intermittent valvtronic issue 2011 328i n51 ok I got a service engine soon light last week code 2a32. eccentric sensor reference. I've been troubleshooting with ista+. it shows the sensor at 0 when requesting 225 degree. when I do the relearn valvetronic stops I can see the shaft move and the sensors shows a different angles. as I run the engine I can see these values changing. Then the engine bucks and sensor shows 0 and 225 again no chance as I rev the engine. if I watch the eccentric shaft as the car runs I see no movement. my question is do I have a sensor problem or a valvetronic issue. should the eccentric shaft stop moving when the sensor stops working. I have read that when the sensor stops working the intake butterfly controls airflow instead of the valvetronic sensor can anyone verify this. has anyone had a valvetronic sensor or motor with intermittent problems?. I'm not sure if I should be replacing the motor or the sensor.
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09-05-2016, 11:21 AM	#2
hassmaschine Major General 3973 Rep 7,215 Posts Drives: "NBO" 330i Join Date: Jun 2014 Location: earth iTrader: (0)	The sensor has failed and its in limp mode, the eccentric shaft moves to full open and it uses the throttle plate instead. Thats why it doesn't move.
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09-05-2016, 11:22 AM	#3
rjahl Colonel 996 Rep 2,287 Posts Drives: Z4 35is Join Date: Jun 2011 Location: Tampa iTrader: (0) Garage List 2012 Z4 35is [0.00]	It's probably the sensor. The motor keeps bringing the eccentric cam to the default position when the two sensors don't agree with each other. Dual sensors integrated in the same sensor part. You can test the VVT motor with INPA.
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09-05-2016, 02:12 PM	#4
fooledyas Private First Class 11 Rep 162 Posts Drives: 2011 z4 and 328i Join Date: Apr 2012 Location: 1175 iTrader: (0)	thank you that's what I though. I was confused because it worked sometimes. It's been my experience that sensors either work, work poorly or don't work.
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09-05-2016, 05:56 PM	#6
fooledyas Private First Class 11 Rep 162 Posts Drives: 2011 z4 and 328i Join Date: Apr 2012 Location: 1175 iTrader: (0)	Already ordered sensor and gaskets. When I get in I'll check the shaft bearings , if sensor doesn't solve then I'll pickup a motor. I deal with a lot of servo motors at work the almost never go , but the ones I work with aren't exposed to heat and weather.
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