No start, no spark.. electrical gurus help please

[GaryR]

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!
:thumbup:

[9dreizig]

That green wire from the CDI to the Distributor is notorious for going bad... I'd check it out

[GaryR]

I'll take a look, by "bad" do you mean broken? Thing is, shouldn't I be getting power to the coil with the ignition on?

[9dreizig]

Right you should.. Here's the link http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_82SC_Part1-2.jpg
that's the diagram. Two wired coming out of the CDI box.. As I recall there's also a switched power wire going into the CDI that is only on when the key is on..

[steven polaski]

Power to the cdi but is it whining ? A good time to replace the cdi with a msd and new coil. Under $ 250.00 for both and you are now in the twenty first century electronics.

[GaryR]

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..........

[steven polaski]

Hey I will p.m my # I live in ct will walk you through it

steven

[GaryR]

Thanks for the kind offer Steven. I'm not sure what you want to walk me through but i'm done with it for today it being Easter and all. In retrospect i'm starting to wonder if the "Fuse 22" is the in-line fuse that sits by itself next to the CDI box. It was pretty corroded inside and i'm not sure but some of the issues were after I tried cleaning it up a bit.. maybe the fuse wasn't seating. All a guess as the manuals don't show it, they just show the schematic with power coming for #22... which of course is odd as there are only 21 fuses on the block!

What MSD box and coil is it? How is the MSD wired in, no way it accepts the OEM 6 prong plug.....

[9dreizig]

Gary, this is not rocket science I'm sure you can do it.. I"d offer to buy Gary some pizza and beer and see if it will come over one night this week and show you how to trouble shoot it

[GaryR]

The thing is I can follow a manual and even figure out some things from a wiring diagram BUT when the manual tells me that the CDI is getting power from a fuse that, from all the info I have doesn't exist, that tosses me.. I assume you mean Steven but Enfield is a good hour away from me. My guess is a call to my shop tomorrow will get me on the right track so we shall see..

[9dreizig]

Sorry I did mean Steve.. I"m sure SOMEONE here knows where that fuse is.... Oh and I totally agree get rid of the CDI box and go with an MDI

[GaryR]

Just ordered an MSD 6AL and Blaster 2 (model 8222). Even if I get around this in the meantime I may as well upgrade a bit..

[steven polaski]

It is very simple, on a scale of 1-10 ,10 being the hardest it is a 3. Great instructions ( pictures) also check the plug pack in the rear fuse compartment sometimes comes loose. My cdi became like yours and started to fail. Also you can sell your cdi if you wanted for about what you paid for the msd box. I put my msd box behind my seat under my roll bar worked out great Good luck.

[GaryR]

Thanks Steven, i'll be looking at the problem again today after speaking with my guy at Hairy Dog Garage..

[930gt-40r]

Gary, if you are interested in doing an MSD box, I am the master of converting these motors to MSD. If you throw me a few beers, I would be more than willing to set it up with you.

[GaryR]

Absolutely! I just came back from my shop and Dan feels it's the Delayed Action Relay that is causing all the havoc right now.. Going down to run some tests, will report back with the results.

When I get the MSD parts I will PM you, you just tell me what beer you like and what you like to eat.. Done deal!

[GaryR]

Wasn't the relay...

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!

[NathanUK]

Nice.

[GaryR]

Still looking for "Fuse 22"... LOL

[steven polaski]

I hate gremlins that whole area is so crowded and full of old conections exsposed to weather and heat. Make sure you put in the new msd box. When mine went I was going about 50 mph and the car just died and just before it stopped a flame came out that was so huge. If you want you can get a msd timing attachment to retard under boost.