Using stock 83 distributor with msd or Crane

[Jahshines]

I can't chase my no spark anymore. I installed a new internal coil in my distributor and really cleaned and lubed the top side of distributor as well.
I know Old Man(Daryl Lane) has used the stock electronic distributor to trigger an MSD ignition. How does the stock pickup communicate with the MSD?
I used the Crane/Allison(now Fast)optical trigger ignition for years on my 914 and it was an amazing change and less expensive than MSD.
Any help is appreciated.

[GDAus]

I can't chase my no spark anymore. I installed a new internal coil in my distributor and really cleaned and lubed the top side of distributor as well.
I know Old Man(Daryl Lane) has used the stock electronic distributor to trigger an MSD ignition. How does the stock pickup communicate with the MSD?
I used the Crane/Allison(now Fast)optical trigger ignition for years on my 914 and it was an amazing change and less expensive than MSD.
Any help is appreciated.

G'Day ..,

Basically, the standard "ëlectronic" distributor on the '80+ models uses a Variable Reluctor (VR) generator to produce a somewhat weird shaped AC waveform to switch the OEM electronic ignition.
Most aftermarket electronic ignition systems usually have some sort of input that a VR generator will trigger. (I think from memory that MSD call that a "magnetic" input)

Just wondering how much faultfinding you have done with the OEM Ignition Module? It doesn't have some of the bells and whistles of a more modern system but it can perform pretty damn well with an upgrade to a modern "transformer" type coil.

I went that route years ago and am running platnium plugs at 1.o mm plug gaps and starts easily and pulls a lot stronger from low RPM.

This is a link to some faultfinding info:
https://www.bimmerforums.com/forum/s...8#post16120818

And one to what coil I switched too:

https://www.bimmerforums.com/forum/s...7#post25194557

Cheers

[Jahshines]

Yeah, I did disassemble my distributor and did the rebuild using this tutorial, including replacing the reluctor or impulse coil, or whatever it's called.
I totally forgot about the writeup at the bottom about the order of testing. I'm at step 3. so far.
This evening I'll start checking pulses at the control module from the distributor.
Thanks for your time

[Jahshines]

I know little to nothing about how to diagnose electronics.
1)have power to both sides coil
2)have power to control module
3) have output to coil from module, but I saw no 'pulsing' just a solid 11+ volts
4)Have a steady 12v from coil output to distributor cap

I bought an MSD blaster 2 today. I have a new cap and rotor, but the rotor arrives tomorrow, so I used the old one. I suppose I'll buy wires, mine are Bosch wires, probably 10+ years old. I also have a shitty meter from harbor freight. Any advice is appreciated.

[Jahshines]

I didn't realize that you can't test negative side of coil with a meter.
My test light was constantly on during cranking, negative side of coil.

[Jahshines]

Any ideas on why I'd be getting -ve DC output from my ICU, enough to (finally) start the car, but not trigger my fuel pump relay or activate my tachometer?

[GDAus]

Hi ...

Ok .. last question first ....

There should have been 2 black wires connected to connector 1 (-) on the coil ... one is the lead from the Ignition Module and the other goes back to the fuel pump relay/tacho/diagnostic connector. If both are connected to # 1 (-) .. then check the big plug on the front inside of the fuse box ... that's where the engine harness connects the the rest of the cars electrical system. The other possibility is the relay connector in the fuel pump relay socket .... it looks like the black wire loops through there on route to the tacho.

AS for your previous questions:

Measuring anything but battery/system supply voltage to a coil with a digital multimeter is sort of pointless.* The output from the Ign Module is a pulsating DC voltage with some messy higher voltage transients and the frequency of the pulses increases with engine speed. If you really need to check exactly what is going on you need to use an oscilloscope to look at the waveform.

Using an incandescent test light often wont show you much either .. it depends on the wattage of the lamp .. because the pulse frequency at cranking spend (say 250 RPM) would be 10 hz .. and idle speed (say 900 RPM) 30 hz. The problem is that the filament in the lamp has "thermal inertia" so it can't go on or off fast enough to be seen if the wattage is too high.

And connecting a test light across the low voltage terminals will short out the coil and the engine stops.
But .. I have found using a 10 watt 12 volt lamp from the #1 (-) to ground and looking at the lamp slightly sideways .. you can usually make out a flicker in the light (depending on how good your eyesight is).

But all is not lost ... if you use a 12 volt LED light .. either across 1 & 15 or 1 to ground .. the LED switches fast enough to show a real pulsing light. The LED draws so little current it wont cause problems across the low volt terminals either.

Testing the coil itself can be done by measuring it's internal resistance.

Measure across # 1 & 15 terminals. Primary resistance around 0.6-0.8 Ω &
# 1 to High voltage terminal Secondary resistance around 6.5-8.0 Ω - for a standard OEM coil for electronic ignition.

* Digital multimeters are designed to measure A.C. 50/60 Hz or straight D.C. ... the pulsating DC from the ICM. Either on the AC or DC setting the multimeter is processing a waveform it is not designed to "read" and simply outputs a number that doesn't really mean a lot.


Chhers