Author Topic: Another Cylinder Misfire....  (Read 10938 times)

jscribble

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Another Cylinder Misfire....
« Reply #15 on: July 03, 2010, 07:32:57 AM »
rg6 is cable television coax. I'll see what I can find on "kabelmetal".

anything here look like it?
« Last Edit: July 03, 2010, 07:34:19 AM by jscribble »
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DesktopDave

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Another Cylinder Misfire....
« Reply #16 on: July 03, 2010, 08:13:54 AM »
I can't dig anything up.  That's really odd.  There is a KabelMetal of Hanover that specializes in wiring of this type but I found nothing else relevant.

I'll bet that this wire is shielded to prevent overloading the coil transistors in the DME.  These coil packs have been troublesome for BMW.  I'd bet you could splice a bit of normal auto wire in there and it'll run like it should.  The amount of RF interference on coil wires is really high, I'd figure BMW put this wire there to eliminate DME resets.  It fits in with my theory that BMW over-did many things on the M42 (forged crank, sodium-filled exhaust valves, coil packs, etc) that can safely be eliminated.

If you wanted to restore the factory wire I'd just cut a length from a less fortunate M42 in a scrap yard.

I did find this great site again...

http://www.bba-reman.com/content.aspx?content=bmw_wiring_harness_faults_and_problems

They have some really in-depth technical explanations of BMW service recalls.  Scroll down until to the lower section of the page and browse the links in the BMW section.  I find that I worry a lot if I read too much of it...
« Last Edit: July 03, 2010, 08:55:30 AM by DesktopDave »
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

jscribble

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Another Cylinder Misfire....
« Reply #17 on: July 03, 2010, 09:19:39 AM »
DesktopDave sounds spot on, as usual. It is highly likely this type of wire is overkill.
Betty - Sold
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dvmotorsports

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Another Cylinder Misfire....
« Reply #18 on: July 03, 2010, 04:16:31 PM »
Quote from: jscribble;94228
rg6 is cable television coax. I'll see what I can find on "kabelmetal".

anything here look like it?


This is the closest, but there is no outer strand.
http://www.alibaba.com/product-gs/235928320/Flat_Flexible_Power_Cable.html

I'll try and get pictures of the dissected specimen up for you guys to have a gander at.

dvmotorsports

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« Reply #19 on: July 03, 2010, 04:20:19 PM »
Quote from: DesktopDave;94230

If you wanted to restore the factory wire I'd just cut a length from a less fortunate M42 in a scrap yard.


You have a better chance of finding a Ferrari in the junkyard here. However, I did just junk my blue 318is. If I can find what yard that is in, then I have a chance. Otherwise i'm up shit creek.

jscribble

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« Reply #20 on: July 04, 2010, 11:25:14 AM »
Luck. Lots of luck.
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DesktopDave

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Another Cylinder Misfire....
« Reply #21 on: July 04, 2010, 12:28:37 PM »
If I stop by at my favorite yard I'll take a look.  Might be able to pull a bit for you.

Never mind, I think I found a solution...I'm trying to delete an alarm from my '89 325i...and guess what?

There are three or four of those wires running through the main harness into the DME plug!  I think they're the same, I'll take some pics when I'm a little further along.
« Last Edit: July 04, 2010, 12:42:16 PM by DesktopDave »
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

jscribble

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Another Cylinder Misfire....
« Reply #22 on: July 04, 2010, 01:07:18 PM »
Cue the superhero arrival music. Desktop Dave to the rescue!
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DesktopDave

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Another Cylinder Misfire....
« Reply #23 on: July 04, 2010, 04:17:33 PM »
More like "Dave just happened to be taking apart a BMW and saw what you needed."  That happens more often than not...
'08 Karmesinrot 128i 6MT
'86 Zinnoberrot 635CSi (M30B32/G265/3.46 torsen LSD)

Sold: '97 Montrealblau 318iS, '91 Brilliantrot 318i, '91 Brilliantrot 318iS

Romrog318is

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Another Cylinder Misfire....
« Reply #24 on: July 05, 2010, 11:13:47 AM »
injector or intake mani leak...
also check the plugs see how they look
and check the Crank position sensor
[SIGPIC][/SIGPIC]
no more M42

dvmotorsports

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Another Cylinder Misfire....
« Reply #25 on: July 06, 2010, 12:29:03 PM »
Quote from: Romrog318is;94287
injector or intake mani leak...
also check the plugs see how they look
and check the Crank position sensor


This is a weak and intermittent spark which is neither of the first two. But I did check the Crank PS, with no luck.

Here is the picture of the wires dissected.

The wire on the left goes over the smaller black wire that is second from the left.


dvmotorsports

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« Reply #26 on: July 06, 2010, 12:30:21 PM »
And is there any way to Ohm out the crank sensor? What would the target value window be?

jscribble

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« Reply #27 on: July 06, 2010, 01:20:01 PM »
Look for about 560 ohms on the meter. Take this with a grain of salt, as it is lifted from r3v.  I need to get a bentley manual.
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Romrog318is

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Another Cylinder Misfire....
« Reply #28 on: July 06, 2010, 05:29:58 PM »
check the spark plug wire boot
my M52 was missing when the coil boot went bad and i went through 7 spark plugs B4 i figured it out
[SIGPIC][/SIGPIC]
no more M42

dvmotorsports

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Another Cylinder Misfire....
« Reply #29 on: July 06, 2010, 07:30:46 PM »
Quote from: jscribble;94331
Look for about 560 ohms on the meter. Take this with a grain of salt, as it is lifted from r3v.  I need to get a bentley manual.


That is damn high. Make sure you get the right book. The common E30 bently doesn't cover the 91 318.

Quote from: Romrog318is;94338
check the spark plug wire boot
my M52 was missing when the coil boot went bad and i went through 7 spark plugs B4 i figured it out


Already changed the wires. No luck.