m30b35 pulse lead connector?

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bmw9818
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Post Fri May 15, 2015 5:51 pm

Quick question have a 85 635 with a m30 engine, has aftermarket leads with the pulse sensor cut off, have a set of e30 leads I'm putting on, but can't find the connection for it?

There's a cps connection by the stat, and two connections at the back going down towards the gearbox automatic,

Thanks
Bristol_Jer
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Post Fri May 15, 2015 6:10 pm

I think there are two crank sensors on the older m30's, one on the flywheel as well? Maybe this would mean it doesn't have the pulse sensor like later m20/m30's?
bmw9818
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Post Fri May 15, 2015 8:03 pm

Hmm... There is a crank sensor, however the aftermarket leads on there atm have the cps lead cut off..

It's running a little bit lumpy and fluctuating on idle, removed the icv and gave it a little clean with some carb cleaner, all pipes look good, revs build up fine, changed the plugs, dizzy cap and arm will change tomorrow,

Also overheating in traffic which I'm hoping is just the waterpump / fan cutxh
bmw9818
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Post Fri May 15, 2015 8:04 pm

There are two similar looking plugs like the cps etc at the back with two wires going down..
Bristol_Jer
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Post Fri May 15, 2015 8:28 pm

Sorry, when you say pulse sensor did you mean the 'extra' wire that clamps round one of the HT leads, or the the actual crank sensor. I just took it to mean the extra wire around the HT lead
bmw9818
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Post Fri May 15, 2015 8:40 pm

Yep the wire around the ht lead,
bmw9818
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Post Fri May 15, 2015 9:38 pm

Yep it's on the front of the head opposite the rad like the m20 engine, I've got a set of bremi leads of an e30 I broke will these be fine, it had a cps lead which il probably just cut off...

Any ideas as to why idle is fluctuating?
Bristol_Jer
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Post Sat May 16, 2015 3:23 pm

On my m30 when the idle was fluctuating it was down to a couple of air leaks, there was a split inlet hose and one of the inlet manifold gaskets had broken up a bit.