Need Help With Automotive Coil

[Lotsokids]

Here's one for you motorheads.
I bought this "Commie car" to fix up, but I have a problem with my ignition. A friend gave me an old coil and it worked, but then the ignition unit (box) stopped working. It was very old, so I decided to replace it with a Crane Cams XR3000 universal unit. I installed it about a week ago and was confident that it would work, but it never fired up. I checked the timing and the pickup in the distributor 4 TIMES. I also tested for spark from the coil. It would spark very little, and then nothing. I had a jumper cable installed from the battery's positive terminal directly to the + side of the coil, then shorting the - side, but no spark from the coil (center lead connected and held near a ground). That is removing the "car" factor completely. I bought 3 more coils thinking I was getting bad coils from the parts store. Now I have 4 coils that produce the same effect - VERY weak or no spark at all. A very good Hungarian mechanic came over today and he has no idea other than maybe my plug wires are bad. I tested for continuity, and they seemed fine.

Another  symptom: There is a small LED light on my new ignition box that lights up when it fires. When I tried to start it, the light would flash as I cranked it over, and it would chug like it was trying to start, but then the flashing would stop and the engine [ignition] was dead after that. The battery is very strong and turns the starter very well. New cap and rotor also (but that doesn't matter if the coil is not firing).

Any ideas? I'm at a loss here. Thanks in advance!

Pretty simple hookup actually.

[racerman_27410]

did you also replace the pickup in the distributor?



KOokaloo!

[flips]

Hi there.

+1 to what racerman said.I would be suspicious of the distributor.Is the timing out 180*?.Have you pulled the spark plug out & checked piston position vs timing mark vs rotor position?.Does it have the optical pickup?magnetic or points?.Is the coil the correct unit for the ignition box? (this could cause the ignition box to fail if incorrect)I would also be checking for bad grounding connections on the ignition box.I'm sorry if you have checked all this stuff already but I hope it helps.

Good Luck & Cheers

Jeff P

[SkyFive]

As I understand you have weak spark, ignition timing is a different issue all together. If you haven't already check the grounds for everything, especially the coil as it mounts to the engine or chassis. I don't suspect the distributor because from your description it sounds like it is triggering the ignition (hall effect?) but the voltage is not getting stepped up. What brand of car is this?

[tmkaos]

What brand of car is this?

Now THERE'S a question for you   

I believe it might be a .. wait for it.... a 



Seriously though +1 on the bad earth somewhere.. The other thing I thought of is that some - and I don't know about your brand - aftermarket spark units have a rev-limiting function, I'm thinking of in particular the MSD series, is there any chance that this unit has that facility and it is default set to 0 revs?

[Lotsokids]

Hi there.

+1 to what racerman said.I would be suspicious of the distributor.Is the timing out 180*?.Have you pulled the spark plug out & checked piston position vs timing mark vs rotor position?.Does it have the optical pickup?magnetic or points?.Is the coil the correct unit for the ignition box? (this could cause the ignition box to fail if incorrect)I would also be checking for bad grounding connections on the ignition box.I'm sorry if you have checked all this stuff already but I hope it helps.

Good Luck & Cheers

Jeff P

LOL to "tmkaos." He obviously knows it's a beautiful 1986 TRABANT. That's why I said I took the "car factor" out of the equation.

It's an optical pickup in the distributor. Everything it timed correctly. Optical to rotor to #1 cylinder top dead center. But that doesn't matter if it's not delivering the spark from the coil. All the grounds are good. I checked them all. The parts store understands it's electronic ignition. I brought the picture above into the store with me. I'll try the plug wires soon and see. It's very puzzling.

[flips]

Hi Lotsokids.

These are probably the instructions you have, but have a look....fair bit of detail,didn't see anything specifically for trabant though.Has a trouble shooting section starting at pg14 near the end.

http://www.cranecams.com/uploads/instructions/90000700.pdf

hope this helps!

Cheers  

Jeff P

p.s once you get it running you can do this....

Trabant Burnout - The Greatest German Car Ever

[Hugh Mungus]

A weak spark can be caused by the Condenser failing - you need a good condenser to get the coil to work properly.

Sometimes they are inside the distributor or they are attached to the coil

Maybe you have forgotten to re-connect it to your new coil... or thrown it away...?

[Lotsokids]

A weak spark can be caused by the Condenser failing - you need a good condenser to get the coil to work properly.

Sometimes they are inside the distributor or they are attached to the coil

Maybe you have forgotten to re-connect it to your new coil... or thrown it away...?

Actually the car never had a condenser. Aren't they only for radio interference anyway?

BUT THE CAR RUNS NOW!

Apparently I received 3 bad coils from the parts store after the original one failed. I explained my problem to the Hungarian parts guy today (with a lot of sound effects and picture drawing). He said I need a Russian coil... LOL. So I installed coil #5 and it fired right up.

So I have a:

- East German "Communist car"
- Italian Fiat engine
- Chinese gauges
- American ignition
- Russian ignition coil

Amazing how all these countries work together. CRAZY... just CRAZY

[flips]

- East German "Communist car"
- Italian Fiat engine
- Chinese gauges
- American ignition
- Russian ignition coil

Amazing how all these countries work together. CRAZY... just CRAZY

Wow! ...looks like you have the International Space Station of Trabants!  .Glad to hear you got it going!.Have you done a celebratory burnout yet!

Cheers 

Jeff P

[simi_ed]

I think the Ignition coils beat him to it!

[Hugh Mungus]

Actually the car never had a condenser. Aren't they only for radio interference anyway?

No, not for RF interference. Maybe I was thinking a bit too "old hat" as condensers were used in older vehicles... but never mind that, you got the motor running which is good news.

[Duane.Hoffeldt]

I know that your problem is solved now, but just something to remember for next time. On really old cars, starter motors were not as efficient as todays models - they would consume high current and often cause a volt drop in the battery of around 2 volts at the time of cranking. Consequently acoil designed to fire on 12volts would produce very weak spark at the time that the engine was being cranked often resulting in a no show from the engine. As a result coils designed to fire on 9 or 10 volts were installed and the wiring was done in such a way that when the ignition key was set to the start position it would feed current to the coil directly from the battery but when the key was set in the run position it would feed current from the battery through a ballast resistor first ( to drop the voltage by around 2 volts) and then onto the coil. Now taking this theory into account is there perhaps just a small possibility that the parts store was supplying you with 12 volt coils all along. This could readily account for why you were getting weak or no spark, because at the time of cranking, the coil was only being fed with around 10 volts (even with a strong battery)

[Dan Filetti]

I don't know a damn thing about coils etc., but I would like to remark that, that was a hell of a second post.  Helpful, unselfish and cogent.  Nice work.

Welcome here Duane.

Dan

[Klavdy]

I concur with our learned colleague, Mr Filetti.
Nice post.