HT leads Resistance

Wed Nov 27, 2013 12:11 am

Hi trying to decide whether to change my HT leads. They have been on the car for circa 10years. Not had any problems with them and no blue sparks in the dark. tested the resistance on each lead with following results are these serviceable readings?

No 7 1.97, No6 3, No5 2.7, No4 2.34, No3 1.7, No2 1.65, No1 1.31. K

They are magnecor aftermarket leads.

Thank You

Wed Nov 27, 2013 11:19 am

I already asked the same question. Here's my thread

http://www.e30zone.net/modules.php?name ... c&t=244343

Wed Nov 27, 2013 3:46 pm

Tommek wrote:I already asked the same question. Here's my thread

http://www.e30zone.net/modules.php?name ... c&t=244343

Thank you from your thread. I guess mine are still well within spec.

Wed Nov 27, 2013 4:02 pm

As long as they are under 10 kilohms or so, they will work.

Wed Nov 27, 2013 7:18 pm

As long as they work, then they're fine, but your results show what a poor quality item Magnecor leads are compared with the OE item.
They appear to vary in resistance according to length, indicating that they are probably cored with what is essentially burnt string, instead of being solid copper conductors terminated with H.V.metal oxide resistors like the BMW version.
Do they have the cylinder identification sensor on #6?

Wed Jan 08, 2014 4:17 pm

Brianmoooore wrote:As long as they work, then they're fine, but your results show what a poor quality item Magnecor leads are compared with the OE item.
They appear to vary in resistance according to length, indicating that they are probably cored with what is essentially burnt string, instead of being solid copper conductors terminated with H.V.metal oxide resistors like the BMW version.
Do they have the cylinder identification sensor on #6?

They don't no. Your making me think now. So the cost saving was probably not worth it. You're correct about resistance dependent on the length.

Wed Jan 08, 2014 5:14 pm

The quality can't be that poor if they've lasted 10 years without problems.

Thu Jan 09, 2014 4:19 pm

Speedtouch wrote:The quality can't be that poor if they've lasted 10 years without problems.

Very true

Thu Jan 09, 2014 7:16 pm

Brianmoooore wrote:Do they have the cylinder identification sensor on #6?

Pretty sure mine don't have that, (also aftermarket leads)!!!

What would/could be the effect of this not being present???
What does it do & how does it work???

Educate me please!!!

Thu Jan 09, 2014 10:38 pm

miniblob wrote:
Brianmoooore wrote:Do they have the cylinder identification sensor on #6?
Pretty sure mine don't have that, (also aftermarket leads)!!!

What would/could be the effect of this not being present???
What does it do & how does it work???

Educate me please!!!

It's essentially a cam position sensor. Doesn't measure it accurately, like on a modern engine, but it does tell the ECU which of a pair of cylinders is on its compression stroke and which is on its exhaust stroke, so that it knows which one of the injector sets to fire.