N46 P101B fault

[Chrism450]

So......
Bought a non running 2005 2.0 z4. Apparently it ran till it was parked on a hill then wouldn't start after. Had cam sensor errors. Found the chain had jumped. All timed back up now and timing aligns spot on as it should after turning it over multiple times but it still won't start. I have fault code P101B. Where should I start? What's the best diagnostics to get?

I've found conflicting information on what the code is for. Vvt learning or air intake temperature or oxygen sensor?

It cranks but doesn't fire, smell of petrol out the back so guessing there no spark.

Many thanks
Chris

 

[enuff_zed]

Not 180 degrees out on the timing is it?

 

[Chrism450]

Thabks for your reply. Definitely not. No 1 cyclinder, front of the car, at tdc, flywheel pin in, curved bit of cams up and locked and the 2 holes on the front of the cam gear plates align. Span it over so many times and triple checked it.

 

[enuff_zed]

Thabks for your reply. Definitely not. No 1 cyclinder, front of the car, at tdc, flywheel pin in, curved bit of cams up and locked and the 2 holes on the front of the cam gear plates align. Span it over so many times and triple checked it.

Was a wild stab tbh.
https://www.bimmerforums.co.uk/threads/e87-07-118i-wont-start-but-cranks-p101b-p1050-p1061.549330/

Does this help?

 

[Chrism450]

That makes interesting reading. I will try it tomorrow....

I'm deleting the fault code using and obd adapter and the torque app, it does clear and is the only fault that really appears

 

[Chrism450]

So, finally got back on it. Checked the timing another time just to make sure and it was all good.
Even did a compression test and was all good.
So tried resetting the motor position on the inlet cam, didn't move. Manually moved in clockwise 90 degrees. Put it back together and the thing fired up first time. Just done 20 mile drive in it with no issues at all

 

[enuff_zed]

So, finally got back on it. Checked the timing another time just to make sure and it was all good.
Even did a compression test and was all good.
So tried resetting the motor position on the inlet cam, didn't move. Manually moved in clockwise 90 degrees. Put it back together and the thing fired up first time. Just done 20 mile drive in it with no issues at all

Do you mean the valvetronic servo motor?

 

[Chrism450]

That's the one, the valvetronic servo motor. It was fully anticlockwise

 

[enuff_zed]

That's the one, the valvetronic servo motor. It was fully anticlockwise

I think it should have been wound back in when refitted, then from memory, when you turn the ignition on the first time it goes through a little calibration dance.

 

[BumpyZ4]

Thabks for your reply. Definitely not. No 1 cyclinder, front of the car, at tdc, flywheel pin in, curved bit of cams up and locked and the 2 holes on the front of the cam gear plates align. Span it over so many times and triple checked it.

There are two TDC positions. You can be at "TDC" on the compression stroke OR the exhaust stroke. Worth checking to ensure it was on the compression stroke.

 

[Chrism450]

Thabks for your reply. Definitely not. No 1 cyclinder, front of the car, at tdc, flywheel pin in, curved bit of cams up and locked and the 2 holes on the front of the cam gear plates align. Span it over so many times and triple checked it.

There are two TDC positions. You can be at "TDC" on the compression stroke OR the exhaust stroke. Worth checking to ensure it was on the compression stroke.

Yep, 4 stoke cycle. Hence why I checked so many times, then double checked