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BMW 320D 2005 - General questions #

Posted by Paul Howd on January 11, 2014, 9:41 am

Year of Manufacture *: 2005
Engine Size and Code *: 2.0d

The situation is that the customer drove through a ford and the engine cut out. The AA restarted the engine and he drove home.

It (seems to) run OK but is a bit lumpy until it has warmed up.

I am wanting to do a crank/compression test but...

(And I know this sounds like a dumb question, but really the situation has not arisen before on an engine of this type )

How does one safely disable the diesel injection so the engine will not fire?

(Unplugging the injectors seems too easy so I thought I had better ask!)

Paul

Re: BMW 320D-general questions

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on January 11, 2014, 10:28 am, in reply to "BMW 320D-general questions"
Mark Carter

You may have the ability to do the test via software within your diagnostic tool and if so the tool switches off the injectors for you, just follow the on screen prompts.

If not then Unplugging the injectors is fine and throw an amps clamp over the main battery cable.

Mark

Modern cars, Its all wizardry and witchcraft

Re: BMW 320D-general questions

Posted by Paul Howd <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5151' width='330' height='300' border=0 style='border:none;'> on January 11, 2014, 2:49 pm, in reply to "Re: BMW 320D-general questions"

Thanks for that.

I thought unplugging the injectors would be OK but I just had that sneaking memory of reading somewhere that unplugging CR injectors and then cranking the engine could cause issues.

On another note, if the engine had been hydrauliced on one cylinder (Possible from the description of the incident) I would have thought I would have got a misfire hot and cold.

With this however, the engine is lumpy/Smokey until it warms up a bit and then runs smooth. (I am logging a fault for a glow plug but I would not expect this to cause a running issue of this magnitude!)

I will report back when I have done a compression balance test but this is for interest only really. I have told the owner (an old customer) that it is probabally going to have to go elsewhere since stripping one of these engines is beyond my resources

Re: BMW 320D-general questions

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on January 11, 2014, 3:26 pm, in reply to "Re: BMW 320D-general questions"
Mark Carter

>>> With this however, the engine is lumpy/Smokey until it warms up a bit <<<

What colour is the smoke ? White/grey by any chance?

Question; how does a Diesel engine actually work, how does it burn the fuel ?

What is the line to line balance readings telling you?

Mark

Modern cars, Its all wizardry and witchcraft

Re: BMW 320D-general questions

Posted by gordon lace <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5375' width='330' height='300' border=0 style='border:none;'> on January 11, 2014, 10:42 pm, in reply to "BMW 320D-general questions"
Gordon Lace

Paul, you could supply the starter motor with an alternatve feed and crank the engine with the ignition off.
Gordon

Re: BMW 320D-general questions

Posted by Paul Howd <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5151' width='330' height='300' border=0 style='border:none;'> on January 12, 2014, 12:35 pm, in reply to "Re: BMW 320D-general questions"
Paul Howd

To Access Starter motor....

First disassemble car!

In the good old days clipping a starter button on to the starter motor solenoid terminal was dead easy!(Unless it was a Renault 5 turbo) But not any more!

A compression check is supposed to be an easy first check! Not a major piece of mechanical surgery!

Re: BMW 320D-general questions

Posted by Paul Howd <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5151' width='330' height='300' border=0 style='border:none;'> on January 12, 2014, 12:44 pm, in reply to "Re: BMW 320D-general questions"
Paul Howd

I see where you are going with that.

But I would have expected the low compression on one cylinder to be quite noticeable even when the engine was warm.

(It has to be said, I have not actually seen a hydraliced diesel that still ran before! Normally IME they are Dead-dead! )

In any case, I have advised the owner that a trip to BMW is in order.

But I would still like a little "Play" (See comment above!) before letting it go!

(I told him a while ago that his 1994 318 would probably outlast the new modern one, though I didn't expect this to be the reason!

)

Re: BMW 320D-general questions

Posted by Kevin Apps <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT2589' width='330' height='300' border=0 style='border:none;'> on January 12, 2014, 4:49 pm, in reply to "Re: BMW 320D-general questions"

Paul

"But I would have expected the low compression on one cylinder to be quite noticeable even when the engine was warm."

A tweaked rod can do this, careful measurement of piston protrution needed.

"(It has to be said, I have not actually seen a hydraliced diesel that still ran before! Normally IME they are Dead-dead! )"

I,v seen lots of diesel,s with tweaked (slightly bent ) rods

Kev

Re: BMW 320D-general questions

Posted by jamie lambert <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1460' width='330' height='300' border=0 style='border:none;'> on January 12, 2014, 7:31 pm, in reply to "Re: BMW 320D-general questions"
Jamie Lambert

Hi Paul
I had a Renault traffic 2.0 dci with the same fault when it warmed up it stopped smoking. It turned out to be a slightly bent conrod, when we got the head off you could see the piston was a few mm lower.

Regards jamie

Re: BMW 320D-general questions

Posted by Bryan Smith <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5330' width='330' height='300' border=0 style='border:none;'> on January 12, 2014, 9:33 pm, in reply to "Re: BMW 320D-general questions"
Bryan Smith

I will agree with above comments in that I have seen them run fine when warmed up. I don't usually get past a relative comp test nowadays as even taking the head off some vehicles just to have look costs far too much.
On the subject of flood damaged cars, how many have been written off due to the owner thinking it's a submarine? I am a small garage and I have had two in here with a third one who purchased a replacement from one of my customers. He told me that the scrap yard won't give him full value at the moment because of the backlog of cars they have to collect

Perhaps it's more good news for our poor VA's????
Bryan.

Re: BMW 320D-general questions

Posted by Alan Lange <iframe src='https://members.boardhost.com/ukautotalk8/info/user=ukat3293' width='330' height='300' border=0 style='border:none;'> on January 12, 2014, 10:42 pm, in reply to "Re: BMW 320D-general questions"
Alan Lange

Hello Paul, time for your customer to dig out his insurance policy! Also, with all these flood damaged cars, did you know insurance companies have for a few years checked with local council's etc to see if the road was closed. (A friend of mine got caught out last year).

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