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BMW 316 Ti N42 B18A 2001 - Non start, code 2782 (Waveforms) #

Posted by Eamonn Greene on May 29, 2012, 6:30 pm

Year of Manufacture *: 2001
Engine Size and Code *: N42 B18A
( Optional ) ECU Type: BOSCH
( Optional ) Scanner Used: AUTOCOM
( Optional) Fault Codes: 2782

Hi,
this BMW just will not start. DTC 2782 will clear but will return every time upon cranking.
The spark is good and the plugs are new.
The injectors are pulsing (ie. lighting a Noid light) and the plugs are wet with petrol. The fuel pressure is 3.5 bar.
My main concern at the moment is the engine main timing and I would appreciate if anyone can help in that regard after having viewed the following 2 waveforms.

Thanks very much,
Regards
Eamonn
PS. This has Double Vanos

Re: BMW 316ti (Waveforms)

Posted by Mark Carter <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 6:48 pm, in reply to "BMW 316ti (Waveforms)"
Mark Carter

>>> DTC 2782 <<<

What do you have as a description and what testing have you carried out with regard to it?

Mark

Modern cars, Its all wizardry and witchcraft

Re: BMW 316ti (Waveforms)

Posted by Eamonn Greene <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5362' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 7:16 pm, in reply to "Re: BMW 316ti (Waveforms)"
Eamonn Greene

Hi Mark,
How are you. Thanks for the fast reply.
2782 = Camshaft Sensor-Exhaust.
I've posted the cam and crank waveforms in my previous post and I don't see a lot wrong with them.
I've also scoped the Vanos Solenoids.

Thanks Mark.

Re: BMW 316ti (Waveforms)

Posted by Mark Carter <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 7:43 pm, in reply to "Re: BMW 316ti (Waveforms)"
Mark Carter

maybe nothing but my Info states 2782 as; Inlet sensor bank two, signal improbable.

Mark

Modern cars, Its all wizardry and witchcraft

Re: BMW 316ti (Waveforms)

Posted by Peter Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 8:47 pm, in reply to "Re: BMW 316ti (Waveforms)"
Peter Mutlow

Hi Eamonn,

You appear to have 2 of the 3 main ingredients to start a vehicle. A compression test is now in order. Is there a story behind the non-start?

Regards

Pete M

Re: BMW 316ti (Waveforms)

Hi Mark,
I don't know what to do. Is your DTC definition refering to the Inlet cam sensor? If so that is scoping okay. Will camshaft errors stop this thing from starting.
I must say I'm fed up at the moment. The Vivaro and now this BMW! I havn't even been able to contact the owner of the Vivaro for the last fortnight.
Back to this BMW:
One would think with good fuel pressure, good spark and the injectors spraying fuel that it would start in some kind of way.
I saw on some Website last night a supposing good waveform for cam / crank synchronisation on an E39. The crank sensor and both cam sensors were Hall sensors just as on this BMW but they were synchonized in a completely different way altogether. To be honest they didn't didn't look right to me but now I'm beginning to wonder.

Peter, I am not aware of any details really. The owner told me that he had fitted new plugs a fortnight ago. I checked for a spark this morning and there was NO KV AT ALL with the coil attached to the plugs but there was 30KV whilst using a spark jumper. I replaced the plugs and the sparks worked correctly again but it still would not start
Thanks very much
Eamonn

Re: BMW 316ti (Waveforms)

Posted by Kevin Apps <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 9:52 pm, in reply to "Re: BMW 316ti (Waveforms)"
Kevin Apps

Eamonn.

Valvetronic ?

As you are deperate try starting it with MAP or MAF disconnected, it may take a lot of spinning or a tow.

Mark

3 of my info systems show the code as exhaust side !! i assume your info is ESI ?
Kev.

Re: BMW 316ti (Waveforms)

Posted by steve w <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1169' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 10:11 pm, in reply to "Re: BMW 316ti (Waveforms)"
Steve Walker

Hi Eamonn

These engines ( if it is an N42 Engine code ) are common for the valve timing jumping due to the chain tensioner getting weak.If you have spark and fuel pressure and injection may be worth checking the valve timing.
Special tools are required to check and adjust it but if you dont have them and want to confirm the theory remove the rocker cover (easy enough) , get number one piston on tdc then check the flat edjes on the cams at the rear of the engine should both be flat and inline if not the timing is out also check if the plastic timing chain slipper has broken up if the timing has jumped.

Hope this is of use.

Steve

Re: BMW 316ti (Waveforms)

Posted by Eamonn Greene <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5362' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 10:31 pm, in reply to "Re: BMW 316ti (Waveforms)"
Eamonn Greene

Hi Guys,
I would like to genuinely thank you all for your help on this BMW.

Peter, I will carry out your instructions tomorrow.

Kevin, you have made a bell ring in my head. I remember the customer saying this morning that this vehicle will start on a tow.
In my ignorance may I ask you the following question? What is the significance of the car been able to be started on a tow in this particular case? And yes this vehicle does have Valvetronic.
Thanks again.
Regards
Eamonn

Re: BMW 316ti (Waveforms)

Posted by Kevin Apps <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on May 29, 2012, 11:57 pm, in reply to "Re: BMW 316ti (Waveforms)"
Kevin Apps

Eamonn

Google valvetronic

this will give you more of a picture on how it works.

If you get this one running correctly (or you get one that is running corectly) check the inlet manifold vacuum !! it may surprise you

.

But then it could be the problem steve w has pointed you to, but if it runs OK with MAF/MAP disconected !!
Kev.

Re: BMW 316ti (Waveforms)

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on May 30, 2012, 12:03 am, in reply to "Re: BMW 316ti (Waveforms)"
Peter Mutlow

Hi Eamonn,

I suspect it will only start on a tow because of low compressions. On cranking the engine is rotating too slowly to build up the compressions.

If i remember from my training days...many moons ago, a vehicle will be difficult or impossible to start if the compressions are below 100psi.

Regards

Pete M

Re: BMW 316ti (Waveforms)

Posted by Eamonn Greene <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5362' width='330' height='300' border=0 style='border:none;'> on May 30, 2012, 6:04 pm, in reply to "Re: BMW 316ti (Waveforms)"
Eamonn Greene

Diagnosed:
I checked the timing today and it is a mile out. Also the Valvetronic motor has stuck in the midway position and won't move even when energized across a battery.
So, it's finished now as far as I'm concerned and I don't really know what the owner intends doing with it.
So thanks to everyone who helped me on this job.
Best regards
Eamonn

Re: BMW 316ti (Waveforms)

Posted by James Eardley <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3143' width='330' height='300' border=0 style='border:none;'> on May 31, 2012, 9:58 am, in reply to "Re: BMW 316ti (Waveforms)"
James Eardley

sorry this is a bit late Eamonn.

This capture is from a N42 B18A the vehicle was running but the capture still is waiting to be confirmed as a known good. Maybe you can post your capture if you repair this car.

The reason I say it needs confirming is I saw a capture recently that both cam waveforms lined up perfectly?

James

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