1990 318iS M42 ignition lead resistance

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jon-m42
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Post Sun Jul 15, 2012 8:30 pm

As the title says, does anybody know what the resistance of the ignition leads should be for the my 1990 M42 318is??

I want to confirm that my HT leads are defective before forking out the HUGE bill at BMW ?

providing they are defective are there any recommendations to hight better quality ones or are the standard set good enough?

lastly where other then bmw can i go to get them possibly at a better rate ?

regards
Jon-M42
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Post Sun Jul 15, 2012 8:33 pm

If all else fails mate i have a good used set
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jon-m42
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Post Tue Jul 17, 2012 4:33 pm

can any one of you tech guys can shed any light in this area please

regards
Jon
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Post Tue Jul 17, 2012 8:18 pm

It's amazing what you can find on the internet

http://www.bimmerforums.co.uk/forum/f17 ... ce-t77109/
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jon-m42
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Post Tue Jul 17, 2012 10:56 pm

Cheers DHFiS

taken from another forum is any body able to confirm this :

Lead 1: 5.08 K Ohm
Lead 2: 4.88 K Ohm
Lead 3: 5.08 K Ohm
Lead 4: 5.25 K Ohm

cheers lads :cool:
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jon-m42
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Post Wed Jul 18, 2012 3:46 pm

£200 from bmw

guys do you all think i should go ahead and get new leads as i am keeping the car as long as i can .... i have no intentions of selling it?

or shall i get second hand used one's ?

Thanks 8)
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BenHar
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Post Wed Jul 18, 2012 4:15 pm

Why do you think you need new leads?

Ben
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jon-m42
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Post Wed Jul 18, 2012 5:43 pm

i am not 100% sure that it needs new leads however i have changed all vacume pipes icv and gaskets and the car seems to be still hunting on idle

it is now leading me to think my leads my have given way after all the miles its done
DHFiS
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Post Wed Jul 18, 2012 6:09 pm

Before I spent £200 on leads that might not be faulty I would get rid of the throttle heater and replumb the air hoses as explained here

http://www.e30zone.net/modules.php?name ... tle+delete

I would check both the butterflies are fully shut when the car is at idle and I would wash out the ICV with carb cleaner.


If the bung is missing from the AFM then I would get a fuel/air ratio check.
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Brianmoooore
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Post Wed Jul 18, 2012 8:29 pm

Spend £46 on an injector refurb, rather than £200 on replacing perfectly good leads!
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jon-m42
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Post Wed Jul 18, 2012 8:52 pm

£46 from which company ??

and what is the trunaround time from the moment i send them off from the moment i get them back as its a daily driver and cant afford to have it sitting on 1 spot for to long.
:cool:
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Brianmoooore
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Post Wed Jul 18, 2012 9:05 pm

jon-m42 wrote:£46 from which company ??
Injectortune, in our trader's section.
Barx325i
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Post Wed Jul 18, 2012 9:12 pm

possibly consider the coil on plug conversion using the m50/m52 units.. An injector clean and COP conversion would work out cheaper and much more effective than replacement oem leads!