82 SC no spark
 

I reinstalled engine after replacing transmission. Car cranks but won't fire. Engine was running fine at the time it was removed.

Fuel ok - I think it is getting fuel (I took out air filter and lifted the flap there and it made loud noise, which I understand means fuel is working).

CD unit getting 12v with ignition on - Car has a permatune (yeah I know) as pictured. It has 7 pins in the unit but the harness has 6 pins; I guess the one pin with its own column is unused? I confirmed pin 5 on the harness going to the permatune (middle bottom) has 12v with ignition on.

Coil - I removed old coil (black Bosch) and shook it and heard nothing. I understand you are supposed to hear oil sloshing around. I checked the primary resistance and it was 0.6 which I believe is outside the spec? I put in an new Accel coil 8140 (which I read here should work) from autozone and no change.

Tomorrow a local Pelican is going to come over and we are going to try his CD unit in my car and see if that works.

Any other suggestions of what to check before that after (if it doesn't work). Thanks

http://i59.photobucket.com/albums/g3...psa8c2873f.jpg

You said you had power in to the CDI unit but did you check for power at the coil with the key turned on?

no how do I do that? there's a sticker warning not to bridge the terminals with the car on so I know that's not it. thanks

Follow the wire from the CDI to the coil, green outside and white inside on my 83sc and sometimes inside a larger black shrink wrap, and test on that post of the coil with a test light! Or you can follow the green wire back to the CDI and check the pin coming out with the test light and the key on!

I have been told to not put another CDI unit in your car but to put yours in his car. that way you won't damage his if it is something in your system that is wonky.

Good advice!

Can't you use a timing light to see if you're getting spark?

I did check for spark with a spark tester. I can't check the coil as described above because the wiring is all wrapped up and impossible to trace without unwrapping.

update - swapped my Permatune in NOLAsc's car and his car ran fine. So ruled that out at least.

Could be the "hall effect" coil in the distributor not transmitting a pulse. Check the value with a ohm meter and compare with specs. You can check it at the green wire connection. Also the pigtail green wire sometimes gets hard and will break.

the green wire seems to be in good shape from what I can see. how do you unplug it from the distributor? there seems to be insufficient clearance to pull it out (fan housing is right next to it). At the harness end the green wire disappears into a wrapped bundle of wires.

Unplug at connection with harness not the dist end. Remove the wire bail first do you don't break the plug.

+1

permatune.com has a diagram of the pin outs. I believe you should have about 675 ohms o' resistance.

You don't need to disconect the green wire to see if it has voltage! Just touch the tester to it with the key on! If you can't get to it at the coil you can push the tester into the plug end of the green wire coming out of the CDI and have someone turn on the key!

The other way is you should have two powered wires in the 6 pin plug with the key on and none with the key off!

Not looking for voltage - looking for resistance in the coil pack to assess if it has integrity.

When you say "push" it into the plug end of the green wire are you absolutely sure the OP knows what you are talking about? I think I know what you are trying to say but it is not profoundly clear. Take the time to word it so there is NO question of the message you are trying to relay.

Look, my first question was "is there power TOO the coil"! If there is, then I am done asking questions. If there is not and there is power going in to the cdi then you need a new cdi!

Make sure the battery is fully charged.

The OP is afraid to remove the distributor. How much does that tell you of his comfort level and experience? Dial it down a notch or two and expand the explanation to include the layman.

Thanks for all the replies.

My green wire does not have a plug end. PO spliced it into the wiring harness that plugs into the CDI (the one with the rubber insulator around the plug). The outer part of green wire is spliced into one wire and the inner green wire into another wire. This was all wrapped in a buttload of electrical tape. It was so neatly wrapped so I had assumed it was stock. At the splice points of the inner & outer wires, I confirmed both wires have good connectivity to the two CDI harness pins on the right side (looking at the plug with the +12 volt pin in the lower middle). One had very low resistance (0.2 ohms or something like that) and the other had several ohms of resistance. I guess it is possible, but highly unlikely, that there's not continuity from the splice point back to the dizzy.

The CDI works. It was tested in another SC this morning.

As I understand it, the coil + and - terminals do not have +12 volts with the ignition in "on" position (with engine not running).

I guess I am going to unwrap more tape and trace the green wire along its entire length. I plan to check continuity of the wires going to the coil + and - terminals and where they are connected or spliced into the harness.

Ok thats what we needed to know!

You are probably correct in that the dist connection is not bunged up (if unmolested). The ground and trigger wire plug into the hall effect coil pack in the dist with a pretty robust connection. Believe there is a rubber seal that keeps out moisture and a machine screw and fastener arm that holds the plastic connector in place against the side of the distributor.

FWIW - I would not call it continuity though as the green wire center trigger wire and outer shielding plug into the dist coil pack terminals. There is 545 ohms of resistance in my two wires. I said 675 above and I think that is a little off. I have a pic buried in here of one that shows 595.

I did unplug the green wire from the connection to my MSD box before testing. There is no resistance from the MSD box between those connection points but I don't have a clue what happens on the box side.

Just set your ohm meter to 2000 and touch the green wire leads and look for the 550-600 ohms with everything off. If you read that range your coil pack is probably ok. If you get an off reading, disconnect the green wire from the Permatune and double check on the dist side for the resistance.

Also, correct on not getting 12V at the coil primary terminals when key is on.

+1

I messed with my two previous Permatune boxes enough to cause the female connectors to push back into the wiring harness at the CD box connection. Some of it was the age of the connector but most of the damage was from a fat fingered noob (me).

I did the resistance test between the inner/outer parts of green wire and got 589 so I think that is ok. I also confirmed continuity of the pins in the 6 pin harness to the inner/outer green wire, +12 volt wire, grounds and coil.

I also killed my battery with all the cranking and it now won't take a charge from trickle charger. grrr......

I plan to put another battery in it. maybe all the wire jostling has fixed a loose connection but that's probably wishful thinking. Last resort is tow to shop if I can't think of anything else to check.

Chill on the towing - a suggestion. :-)

For $300 you can install an MDS box. For a few hundred more you can get a used or rebuilt Bosch box - I think?

How you are able to connect the six pin wire connector to a seven pin permatune box? I don't get that.

Here is your box connection all blowed up:
http://forums.pelicanparts.com/uploa...1355796738.jpg

Here is a six pin Bosch box - fuzzy but still viewable

http://forums.pelicanparts.com/uploa...1355796823.jpg

Your just plugs in? How? Seems like it wouldn't fit.

You sure you have the rotor in there?
Sure the coil wires are on the correct terminals?
14 pin connector nice and snug connection? No pins pushed back?

my Permatune is the 8 pin version (really 7 since one unused) for the 930 and it uses a plug and play adapter to connect to the 6 pin SC harness. 2 of the 8 pins on the cdi are unused. it was working perfectly in the car like this for 2 1/2 years I've owned it and probably many years before that. yesterday I swapped it into NOLAsc's SC (with the adapter harness) and it fired up immediately. so the CDI and its harness is not the problem.

all the pins look fine. the rotor and cap look fine (2 years old).

I will check the coil wires but I'm almost certain I put them in the right place.

I guess one possibility is the new coil I got is bad out of the box. unlikely but not impossible.

my Permatune is the 8 pin version (really 7 since one unused) for the 930 and it uses a plug and play adapter to connect to the 6 pin SC harness. 2 of the 8 pins on the cdi are unused. it was working perfectly in the car like this for 2 1/2 years I've owned it and probably many years before that. yesterday I swapped it into NOLAsc's SC (with the adapter harness) and it fired up immediately. so the CDI and its harness is not the problem.

all the pins look fine. the rotor and cap look fine (2 years old).

I will check the coil wires but I'm almost certain I put them in the right place.

I guess one possibility is the new coil I got is bad out of the box. unlikely but not impossible.

Cool - It has to be something silly.

I can't imagine that you have two bad coils -- the one that ran right before the engine came out and the replacement...

Ignition coil..........
 

schumicat,

Could you post picture of the new ignition coil? There is a particular Bosch ignition coil that is made south of the border that tend to be bad coming from the box. Keep us posted.

Tony

My new coil is a univeral Accel coil sold at Autozone and most FLAPS. I've read in posts here that it should work fine with an SC running permatune. However, I'm now thinking my old coil (Bosch black) may be fine. The resistances check out fine. It doesn't make slosh sound (oil) when shaken, but I'm not sure that is definitive. I may try to swap it back. I thinking (hoping) the problem is a wire that needs to be jostled the right way....

Get down with your bad self on checking continuity. Tedious crap work but I bet that is where your problem lies.

Double check the 14 pin connector in the far rear driver's corner. If you pulled the engine that had to be disconnected. I have not researched to determine what feeds what but that connector is the life blood of the car. There are male and female mating connectors that can get pushed back out of the housing and you will not have a clue unless you pop it open and take a look.

That's the connector by the heater blower fuse panel? Could there also be a problem at the one by the firewall? I've heard you could spread the male parts a bit for better contact (that doesn't sound right).

Jaysus Schumi... You gotta get that car back on the road.

update... new battery, old coil back on and ....

http://i59.photobucket.com/albums/g304/schumicat/911start_zps4ebf9694.mp4

Of course now the fuel pump is squealing like Ned Beaty in Deliverance. It only started doing that when I was trying to diagnose the lack of spark and doing lots of cranking. Car will stall if I try to give it gas. I think the fuel pump is dying and is barely moving any fuel. But at least the damn thing started.

thanks to all who helped.

Very cool.

so your problem was a bad battery?

no, that was effect not cause. if the starter cranks the battery isn't the problem. all the cranking killed the battery.

how did u fix it? I have an 84 911 3.2, couple of weeks ago it died in traffic and wont start. I have no spark, Relay is operational, cylinder head temp sensor's resistance is within range...