E23 745i spark plug wires part number differences

[spitfire980]

Hi guys

My friend is in need of spark plug wires for his '86 745i, vin 0720902.

Would it be correct to assume that since the M106 is basically a B34 to use B34 spark plug wires or does it have to be M106 specific, BMW part number 12121705719?

Thanks

[Hit Man X]

An '86 model should have an 875xxxx VIN or 1150xxx for Highline, maybe export models are different? I am interested if you are able to take a picture!

In any event, Motronic 745i has a sensor wrapped around the number one spark lead. This is critical for the knock and boost systems to function.

Car will drive without it, but not best way to go.

[spitfire980]

An '86 model should have an 875xxxx VIN or 1150xxx for Highline, maybe export models are different? I am interested if you are able to take a picture!

In any event, Motronic 745i has a sensor wrapped around the number one spark lead. This is critical for the knock and boost systems to function.

Car will drive without it, but not best way to go.

ill try to get the whole vin, so would a B35 sparkplug wire be more suitable since it has that sensor on the #1 lead?

sample pic:

[Hit Man X]

B35 is on number six from what I remember and the connection is different...but signal output is the same best I can tell.

What is the problem with buying the proper set?

[spitfire980]

B35 is on number six from what I remember and the connection is different...but signal output is the same best I can tell.

What is the problem with buying the proper set?

i cant find anything matching that part number available

[Hit Man X]

How is the condition of your 'pulse generator' as BMW calls it on the 745i?

If still in operable shape, why not have a set of plug wires built? Or you could send the thing to Kingsborne for a set to be produced with your pulse generator.



If you want to do the B35 wire set swap, you would have to convert from the round plug to the flat unit. Signal output is the same best I can tell by examining schematics, but have not tested this.

http://www.kingsbornewires.com/product-p/12-7721.htm You could buy that and have them install your pulse generator on the number one wire. Kingsborne used to sell the 05/83+ Motronic wire sets, but I have heard from a few people that pulse generator is NLA.

[madman2]

An '86 model should have an 875xxxx VIN or 1150xxx for Highline, maybe export models are different? I am interested if you are able to take a picture!

In any event, Motronic 745i has a sensor wrapped around the number one spark lead. This is critical for the knock and boost systems to function.

Car will drive without it, but not best way to go.

Hi Hit Man,

Thanks for the valuable feedback as this is regarding my 1986 745 car with vin WBAFJ990600720902 so does this change any of the previous assumptiins? Thanks

Sent from my SM-G935F using Tapatalk

[Hit Man X]

Neat, looks like a Japan market 745i VIN!!

I think those have a -024 or -025 ECU, pretty rare.

Still go with the above for plug wires, Kingsborne.

[timgal1234]

I bought a set of b34 plug wires and twisted the boot off to get the pulse generator on to the new wires. It worked but it's not easy to get that boot off I used a pocket screwdriver to get between the wire and boot and loaded it up with silicone spray. Then I twisted the boot off.

[Thradya]

Old topic but just in case - bought yesterday a NGK wire set (according to their catalogue for 728i - wires only, without the enclosure) and one of the wires has the boot removed to allow for installation of pulse generator - it's even mentioned in included manual.

[nikoor]

NGK does make a specific set for 3.4 745i, part is RC-BW1104 / 44239. Cyl. 1 spark plug socket is removable for pulse generator. Price was 209 euros here in Europe, had already new pulse generator from BMW for ~80 euros two years ago.

Wires are bit longer than originals and don’t come with plastic case or rubber hat for coil wire. Installing pulse generator was snug fit on wire end, but did pass through after minor tampering of compressed connector.