Gary R.

It finally came time to turn the key this morning and she cranked over perfectly with the sound of the fuel pumps whirring away. And then she cranked some more.. No start. I pulled a plug wire and stuck a good plug in it (grounded it) and cranked away. No spark. Checked to see if I had knocked off any wires doing all the suspension and exhaust work and all looked good. Checked pin 15 going into the CDI unit and it has power with the ignition on. Checked both sides of the coil and there is no power getting there with ignition on or off. At this point i'm stumped. I'm going to try and get the wiring diagram off the PDF manuals I have but I sure would appreciate any input..


Happy Easter!

nathanUK '81 930 G50

Can you hear the CDI whining when you turn on the ignition (no cranking needed, just ignition on) ?

Gary R.

Nathan - lot's of noise with the key on, should I be listening to the CDI box (left side of engine bay) itself?

PorschePhD

Yep, it shoudl hum when it is on. Check that first.

Gary R.

Thank you for the reply Stephen.
And it just gets better... first of all, where the heck is "Fuse 22" that gives power to the CDI box through the red/wt wire on terminal 15? I swear it had power when I started out this morning (w/ign on) but now its dead. Also it seems that I am intermittently not energizing whatever is making the racket in the engine compartment when I switch the ign on... dash lights up, starter will engage, but all is quiet back there. I'm wondering if the ign switch is toast considering it's been bypassed (using a starter push-button) already. Is there a way I can run power to the CDI directly? Maybe a jumper into terminal 15 and go from there?

Or maybe i'll just bring it to my shop..........

Gary R.

Just ordered an MSD 6AL and Blaster 2 (model 8222) coil so my guess is tomorrow it will work perfectly (By that I mean the OEM stuff will magically work). Either way it's an upgrade in reliability though i'm pretty sure the CDI box/coil are fine as far as my current problem goes.

PorschePhD

It is up in the front Bonnet.

The MSD is not going to help if you don't have power back there. As long as you only pulled the yellow line from the starter the switch shouldn't be the issue. Also check the rear plug and make sure it is seated in all the way.

Gary R.

I understand about the MSD not curing this issue, just bought it as an upgrade to do AFTER I get this running as i'm fairly certain the existing components are serviceable. Not sure what wires they used for the starter button but it worked fine for a few weeks and right up until I parked her several weeks ago to do the suspension/brake and exhaust upgrades. I assume by the rear plug you mean the 6 pole into the CDI box? It's seated fine, but shows no power to pin 15. Stephen, do you know what are they referring to with Fuse #22 in the Bently manual?

PorschePhD

I will look up in the morning to see what the heck they mean. The manuals have a lot of errors in them.

No, I mean the 15 pin plug.

Gary R.

The one in the tail end of the casing holding the heater fuses? I cleaned and reseated that one in the course of things today. Or is it another one?

Thank you, I very much appreciate your input! Maybe I knocked something loose during the Camber King and Smart Racing sway install up there.

PorschePhD

No, the CDI fuse is in the front panel.

Gary R.

Just returned from dropping the SC off for a DE tech at my shop and Dan seems to feels it is the Delayed Action Relay that is causing all the havoc and gave me a couple things to test out. I'll report back with my findings...

PorschePhD

Yep that could do it. Pull it and jump the terminals.

Gary R.

Nope, wasn't it. And the CDI is good too.. There was some kind of bad connection in the 15 pin connector. If I grabbed it and yanked upward the CDI would start whining, then it would cut out, then I would yank it and on it would go. Took the whole thing off, dismantled the plug and cleaned it up the best I could (along with the grounds), reassembled and the car started right up and purred like a kitten!

A930Rocket

Good news!

It's amazing how you can work on the right front tire or what ever and the CDI/ignition goes out? LOL. I can't tell you how many times I've worked on one thing only to have another not work.