Extra cable on spark plug cables? E30

[Kepes 231]

Hello,

I'm currently in the process of replacing some of the ignition system parts.

The new ignition cables I have seem to have an extra cable (old wires didn't have this) coming from the distributor end of cable 6.
If anyone can offer any help as to where this cable might plug in and its purpose the would be really appreciated.

Edit: I appear to have the wires for 1988+ E30's . Mine's 1987. Would these still work if I didn't plug the extra wire in? Or would it be a better idea to just get the right kind?

Sorry if my description doesn't make sense, photos attached

Edited December 3, 2013 by Kepes

[_ethrty-Andy_ 2132]

its for spark detection, helps the DME run. something like if it doesn't pick up the spark plug firing it shuts down the engine to prevent damage. Should be connected to the lead that goes to the spark plug closest to the firewall correct? At least thats what it does on M70 which is very similar.

At a guess, is your car a prefacelift? because it may not have that technology? but those are later leads like 1991 etc M20 rather than 1986 etc

Edited December 3, 2013 by _Ethrty-Andy_

[Kepes 231]

At a guess, is your car a prefacelift? because it may not have that technology? but those are later leads like 1991 etc M20 rather than 1986 etc

Yeah pre-facelift. Purchased from BMA Auto Parts, searching for 87 specific parts. Looking at it now on their website it say's it fits. Judging by your description, using them without that cable isn't an option right?

[_ethrty-Andy_ 2132]

Yeah pre-facelift. Purchased from BMA Auto Parts, searching for 87 specific parts. Looking at it now on their website it say's it fits. Judging by your description, using them without that cable isn't an option right?

Happy to be told I'm wrong, but those should be fine for your car. I have never owned a prefacelift. You will just need to zip tie that wire up, or cut it off. Its only a coil inductor type thing, it is not electrically connected to the cable it self.

but if the female side of that connector is on your car but just not currently used, it is on the front of the engine under the intake manifold, approximately on top of cylinder 1

On the other hand, contact the people you got them off, see what they say, always better to have the correct parts for you car

[slideways 47]

Thats the cylinder identification sensor thats used on the facelift motronic 1.1/1.3. You dont need it and i would look at cutting it off.

[Kepes 231]

Had a good look for the female end but don't think mine has it. Seems to be okay without that connected so I think I'll give it a go without it. If anyone thinks thats a bad idea let me know :-) thanks for the help

[_ethrty-Andy_ 2132]

Had a good look for the female end but don't think mine has it. Seems to be okay without that connected so I think I'll give it a go without it. If anyone thinks thats a bad idea let me know :-) thanks for the help

Its not a bad idea.

but i would be contacting your parts people you got them off and try to get the correct part, you may even get a refund as the one you need is a simpler part?? do this before you fit them, they won't take them back once fitted!

[Kepes 231]

Its not a bad idea.

but i would be contacting your parts people you got them off and try to get the correct part, you may even get a refund as the one you need is a simpler part?? do this before you fit them, they won't take them back once fitted!

haha you're definitely right, but im sure you know just how tempting it is to get your car back up and running asap! That said, I'll contact the people i got it from and see what they have to say. Thanks!

[Kepes 231]

In case you were wondering, I contacted the people I bought these from and they said it would work fine - just zip tie the extra cable away from any moving parts. Did exactly that and everything works fine. Again, thanks for the advice.

[Jono51 59]

its for spark detection, helps the DME run. something like if it doesn't pick up the spark plug firing it shuts down the engine to prevent damage. Should be connected to the lead that goes to the spark plug closest to the firewall correct? At least thats what it does on M70 which is very similar.

At a guess, is your car a prefacelift? because it may not have that technology? but those are later leads like 1991 etc M20 rather than 1986 etc

No, if there was no spark it wouldn't be running anyway

it is to do with injector pulse simultaneously or semi sequentially in motronic 1.3 E30,

not needed on OP car

Edited December 4, 2013 by JKSE

[deedub 32]

On 12/3/2013 at 6:39 PM, slideways said:

Thats the cylinder identification sensor thats used on the facelift motronic 1.1/1.3. You dont need it and i would look at cutting it off.

This thread saved me from going down a rabbit hole. Searched all around and found an E34 M5 thread where someone went into detail about how the pulse generator works.

But like OP I found that my wire kit didn't have the cable 6 pulse generator. Thought previous owner had cut it off and hidden the connector away somewhere. Couldn't find it anywhere.

What confused things more was my model and year of car on realoem showed the wires with the pulse generator (and I couldn't seem to find anything in the bentley manual about it). So I figured it was missing. After reading this I realise now it never came with my car (1987 E30).

Figured I'd revive this in case someone else is searching the web for the same thing.