No spark even after new coil.

hawaii83cab · 04-18-2015, 10:05 PM

Car (83 RoW Cab) has been a no start for a week now. Thought I was dealing w/ a CFI problem and on a whim pulled a plug to check for spark. Found no spark and the Bosch coil looks like it had seen better days. Popped in a new Accel coil and thought that would fix it. Still no spark. With the key in the running position I can hear the CDI box making noise. I ran out of sunlight before I could check for any broken wires to the coil but will be doing that first thing in the AM. Any other ideas on what I can check out? Thanks in advance!

JSV798 · JSV798's Garage

If it's like my 78 SC check the connector behind the distributor; I've had trouble with this connector

scottrx7tt · 04-19-2015, 08:03 AM

Could be the green wire coming out of the distributor. They have been known to fail. Could also be the pick up coil inside the distributor that has gone bad.

911SauCy · 911SauCy's Garage

check all associated fuses and relay, then the green wire, then...if those are all good, likely they CDI Box

hawaii83cab · 04-19-2015, 10:43 AM

Quote:

Originally Posted by 911SauCy

check all associated fuses and relay, then the green wire, then...if those are all good, likely they CDI Box

I had all these on my list to check except the relay. Can you give me more info on it? Thanks

hawaii83cab · 04-19-2015, 11:53 AM

OK I just check for voltage at the coil with the key on run. No power found. Checked all the fuses in the frunk and they seem to fine w/ the exception of one that was broken for a front running light or something. I will continue to use the search function but if anyone could help that would be great.

hawaii83cab · 04-19-2015, 01:36 PM

I just took this pic of the wire going to the distributor. Seems to be hooked up. You can just see at the very end where is exposed to the elements. I have also verified that the coil is not getting power when you crank it over. If the CDI does not get a signal it will not fire the coil, correct? Running out of ideas here so any help would be great.

jason2guy · 04-19-2015, 02:17 PM

that wire is toast and most likely your no start issue. youll have to remove the dist to replace it and a timing light for install.

Bob Kontak · Bob Kontak's Garage

Quote:

Originally Posted by hawaii83cab

I just took this pic of the wire going to the distributor. Seems to be hooked up. You can just see at the very end where is exposed to the elements. I have also verified that the coil is not getting power when you crank it over. If the CDI does not get a signal it will not fire the coil, correct? Running out of ideas here so any help would be great.

You will not get constant 12 V at the coil of an SC. "Ferdit it" as my son, when two years old, used to say.

Your green wire is in need of replacement even if sending a signal - which is highly suspect. Looks really tired and lacking integrity.

That should be a sealed unit where the wire goes into the connector.

hawaii83cab · 04-19-2015, 02:47 PM

OK, will have the dizzy off later today. I hope there are the parts on island to fix it. If not have to mail order it. Hawaii is high corrosion on everything so it probably ate up the inside of the wire. Hope this fixes it!!

jason2guy · 04-19-2015, 04:12 PM

before ordering parts you have to figure out what you need. you might have 1 long wire going all the way to the cdi. if you do some splicing and wiring has to be done, and by the looks of that thing i wouldnt expect the rest of the wire to be in good shape. its not a difficult process, just a little finicky. it involves getting a short piece that connects to the dist, then a longer piece that plugs into the new short piece on one end and the cdi on the other end

Walt Fricke · 04-19-2015, 07:50 PM

You shouldn't have to remove the distributor to disconnect the wire in question. If you can get a short screw driver on the slotted fastener which shows up in your picture, screw that out. Then you can just pull the plug out of the distributor.

Using an ohmmeter or a continuity tester, pull the CDI box plug. You should find continuity to one of the grounds for one wire, and one of the other connectors for the other. If you don't, that connection is broken.

I don't think the reluctor coil inside the distributor is prone to failure. You can check for continuity by plugging back in the connector, and testing at the CDI box plug connectors you have identified.

If the CDI box buzzes, you've most likely got 12 volt power to it. But easy to check the plug to find the 12V terminal and see if you do have 12V.

hawaii83cab · 04-19-2015, 08:16 PM

Just pulled the dizzy out and cut the line since it was one piece all the way to the harness. It's pretty ugly on the underside of the plug. Most of the wire is brittle all the way to the harness, I'm not sure what to do about that. I doubt the replacement plug will come long enough to replace all that wire.

fintstone · fintstone's Garage

Looks like the green wire, part number: 930-602-907-01-M14

http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search_2014.cgi?command=show_part_page&please_wait=N&SUPERCAT_FLAG=Y&make=POR&model=911M&section=elignt&page=9&bookmark=25&part_number=930-602-907-01-M14

jason2guy · 04-19-2015, 08:44 PM

you have to do the fix i mentioned. all you need is the short wire that pelican sells, a female bosch connector and some wire suitable for this application

hawaii83cab · 04-19-2015, 08:56 PM

Quote:

Originally Posted by fintstone

Looks like the green wire, part number: 930-602-907-01-M14

Porsche 911 (1974-1989) - Ignition - Page 9

I did see that listed. Would have been nice is they included the female connector as part of that item. Now I'm here trying to piece it together..

hawaii83cab · 04-19-2015, 08:59 PM

Quote:

Originally Posted by jason2guy

you have to do the fix i mentioned. all you need is the short wire that pelican sells, a female bosch connector and some wire suitable for this application

Is there anything stopping me from cutting the connector off and just soldering the wires? Seems like a more permanent fix.

jason2guy · 04-19-2015, 11:15 PM

the connector that goes into the dist has the wire molded into it. im sure you could rig up something that would work but doing it this way will make for a lasting repair. the only part you need new is the small wire coming out of the dist.
if you have a pickurpart there you could find the female connector with wires attached and just splice it in

hawaii83cab · 04-20-2015, 06:54 PM

Update: I got the new plug soldered in today. Still no spark. Upon further inspection I believe the whole wire is compromised. You can see it's no longer green it's brown. It's hard and brittle when you try and bend it. The first pic shows wear marks. The second pic shows how the outer covering just stripped its self away. What a nightmare.

.... I pulled the black tape off the harness to inspect further and that's where the wire turns green again. Should I replace the wire to this point? We're talking a good 8 inches.

Bob Kontak · Bob Kontak's Garage

Quote:

Originally Posted by jason2guy

if you have a pickurpart there you could find the female connector with wires attached and just splice it in

Bingo!! Exactly what I did.

Snag the connector from and old VW or Audi.

Splice it close to the CDI connector where the core and shield wire split.

Also make sure the female pins have not backed out in the 6 pin CDI connector. I think they are supposed to lock in place but after 30+ years.......