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no spark, replaced coil & ignition module, what next?

Maybe it is the wire going back to your dash and the tach, pinched somewhere?
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Art - That is a GREAT CALL! Intermittent pinch could definitely floor this thing, and make the tach go wizzy-wig. Disconnect the tach wire at the coil to be sure. Perhaps even his tach is shorting to ground? FTW!!! Now this is what forum speak is all about. I love it. :cheers:

PS Still concerned about his pin 12 measurement though. Unless he's 100% sure he made contact with the conductor.
The ground you see on the coil negative: it should not be there, of course, except when the coil is being discharged.
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fyi, and others... the discharge actually happens when the ground is released. Coil windings have the inherent nature to want to maintain the existing magnetic field and current flow once power is removed. Being grounded initially sets up the coil for a discharge, which results in a rather large amount of current (via magnetic field collapse) being induced into the secondary coil, (when the circuit is broken - ie ground is removed) which generates the actual spark.
 
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Thanks for all of the support. I guess clipster's post 13 was the next piece of the puzzle I was having a hard time pulling out of the documents. I admit to trying to rush the process...I have a transmission swap to also get done this weekend in my other car. Can't start that work until I have the 240 working again.

I realized my "clicking relay" comment was dumb so right after posting that I took it apart and watched both sides move.

I also should have mentioned that I checked both coils, they're both within spec. I had read on here that it was possible for a coil to measure good but still be bad, so I put a new one in.

My diagnostic socket definitely needs to be fixed. I did get it to light up once in pin 6 (never in pin 2), but I couldn't get any codes to spit out.

I did also check the distributor, it was fine. I didn't worry about that because I know I'm not sending a spark out of the coil.

So going forward, I will try finding an analog meter and disconnecting pin 5 to see if the negative side goes back to 12v. I think I tested it before and got less than the 2v it was supposed to have according to what I was following. It seems that signs may be pointing to the EZK? I will do the rest of the tests tomorrow.
 
Dunnp2, please try Art's suggestion FIRST. Disconnect the extra wire from the coil negative side - which feeds your tach.
Always do the easiest thing first.
 
Woah, I didn't refresh the page since 10:45. I missed the last three posts.

When I measured pin 12, it was with the connector unplugged so I could make contact with the end where it would connect to the LH2.4 box. That's what the greenbook said to do, right?

I have been wondering about that wire to the tach. I actually ran another wire separate from the white/red one to the tach when I first having weird RPM values a few months ago. It didn't change anything, but I realize now that it was a stupid thing to do. I didn't remove the white/red wire on the coil side, I just unplugged it from the tach and ran a new wire to the same connection on the coil. First thing I'll do tomorrow is remove the white/red wire that goes to the tach.

The first thing I did when the car died was remove my new tach signal wire, so the tach itself was out of the equation (thinking the tach was going bad and shorting, not that the wire is grounding).

That would make a lot of sense, actually. My tach sometimes works and sometimes gets 'stuck' at some low RPM value, but just recently (like, right before it died...) it was approaching zero. The last couple of days while driving it around it basically stayed at zero when it got 'stuck' but it did give accurate RPM values most of the time.

clipster said:
Art - That is a GREAT CALL! Intermittent pinch could definitely floor this thing, and make the tach go wizzy-wig. Disconnect the tach wire at the coil to be sure. Perhaps even his tach is shorting to ground? FTW!!! Now this is what forum speak is all about. I love it. :cheers:
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^agreed! If that's what the problem is, many thanks will be due. I probably never would have thought of that until I either replaced everything else or gave up and started installing an aftermarket EMS.
 
^agreed! If that's what the problem is, many thanks will be due. I probably never would have thought of that until I either replaced everything else or gave up and started installing an aftermarket EMS.
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Neither would anyone else have thought of it either. Lol... except for Art. :woowoo:
 
dunnp2 said:
Woah, I didn't refresh the page since 10:45. I missed the last three posts.

When I measured pin 12, it was with the connector unplugged so I could make contact with the end where it would connect to the LH2.4 box. That's what the greenbook said to do, right?

I have been wondering about that wire to the tach. I actually ran another wire separate from the white/red one to the tach when I first having weird RPM values a few months ago. It didn't change anything, but I realize now that it was a stupid thing to do. I didn't remove the white/red wire on the coil side, I just unplugged it from the tach and ran a new wire to the same connection on the coil. First thing I'll do tomorrow is remove the white/red wire that goes to the tach.

The first thing I did when the car died was remove my new tach signal wire, so the tach itself was out of the equation (thinking the tach was going bad and shorting, not that the wire is grounding).

That would make a lot of sense, actually. My tach sometimes works and sometimes gets 'stuck' at some low RPM value, but just recently (like, right before it died...) it was approaching zero. The last couple of days while driving it around it basically stayed at zero when it got 'stuck' but it did give accurate RPM values most of the time.

^agreed! If that's what the problem is, many thanks will be due. I probably never would have thought of that until I either replaced everything else or gave up and started installing an aftermarket EMS.
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*CRITICAL INFORMATION* (as cited above in BOLD )
I've had a dozen or so tachs go bad over 50 + years I've been at the trade....only ONE ever failed
"dead short" at the outset...all of the others "degraded over time" and left their trail of broken sparks
all over the tarmac...the really SWELL thing about having all the GREENBOOK stuff on disc is
that you can "print what you need" and take it to the car - I carry a black / blue pen and a red ink
pen along w/my clipboard...as I go thru the diagnostics "logic tree" or flow chart - I write down my
findings - any that do NOT AGREE with the *expected results* get circled in RED and then I direct my
search in that direction before I proceed...it sounds like I get "side-tracked" *BUT* the flow chart is
set up that way for a reason....

BTW, you'll notice a LOT of time I post queries back at the person asking for diagnostic help
when they fail to "ID their car"...THIS is ALWAYS the final line in my query:

YEAR
MODEL
POWERTRAIN
TRANSMISSION
*ANY MODS YOU'VE MADE*

that is part of my "worksheet" for "cold diagnostics" when I'm presented with a "dead car"
once I've verified COMPRESSION and FUEL / SPARK DELIVERY I can progress along
the path indicated by the "missing leg" to the THREE requirements for running...

OP has done DUE DILIGENCE and *NOW* knows that any MODS made may adversely
impact a diagnostic session....a VALUABLE LESSON IN AND OF ITSELF (and I've
been reminded of that every time I start making *assumptions*)...yes...us old guys
can *miss indicators* along with the rest of the crew...the object is to catch yourself BEFORE
you commit to a "side track" or to "proceed REGARDLESS" path....

keep us posted...and take a breath BEFORE you do the trans swop!!:nod:
 
woo! Forums to the rescue!

I cut the tach wire, had 12v on both sides of the coil, and she fired right up!

Many thanks to everyone. Now I have much better troubleshooting knowledge AND an almost completely new ignition system! Definitely a good experience.
 
Good news!
Nice to see success when someone listens to advice rather than firing the parts cannon and complaining when it doesn't solve the problem.
 
Currently tracking down what seems like the same exact issue!

A few months back while removing the gauge cluster something started smoking. Checked for blown fuses and melted wires and and oddly found none :wtf: Put the cluster back in and everything was fine for a month or two. Then the tach goes out, but comes back from time to time and seems to read accurately. The entire time I was battling intermittent no crank issues and dead batteries.

Then one day, just like the OP, cruising through a parking lot and it just dies, popping the clutch does nothing, jumping didn't work, until I discovered the engine ground strap had worked it's way loose on the fire wall. Tightened it up, got another jump and it cranked right up. I thought the problem had been solved....foolish.

Now it cranks, but won't start and fuel is not the problem as I've coasted to the side of the road, played with the plug wires, distributor cap, and coil wires and on respective occasions and gotten it to start again. Naturally the first thing I did was replace those parts (all pre-dated my ownership anyway), but the no start issue persists.

I've disconnected the tach signal cable from the coil, but my battery is now too low to crank, so I'll get a jump and see if that does the trick.
 
dunnp2 said:
woo! Forums to the rescue!

I cut the tach wire, had 12v on both sides of the coil, and she fired right up!

Many thanks to everyone. Now I have much better troubleshooting knowledge AND an almost completely new ignition system! Definitely a good experience.
Click to expand...

Awesome! In spite of the noise around here in certain parts, there is also a ton of knowledge, experience, and out of the box thinking when the chips are down. Just reading this has been good for me. :)
 
dunnp2 said:
Good luck, keep us posted.
Click to expand...

Actually, the plot thickens....

I went out and bought an MSD blaster SS coil, wired it up, and it cranked up first try, in fact it didn't even seem like it took a full rotation, by far the quickest startup since I've owned the car! It idled for about 5 minutes, then shut off :wtf:

Now I"m in the process of checking the power stage. This one looks original, and I have a late model Bosch I can swap in, but this is starting to get annoying
 
Replaced the powerstage, still no start.

I did however notice that the speedometer bounced, like a tach while cranking and the tach remained still. Perhaps that smoke was insulation for tach and speedo signal wires, and they are somehow involved in this fiasco?

I'm really stumped by the fact it start up so quickly, idled great, and rev'd happily for 5 min then just died and refuses to start. It seems like the problem was the coil....until I fixed the coil, now the problem has moved
 
Replaced the Crank Position sensor, since the one I was using had some exposed shielding that I wrapped with electrical tape. Here's the best part....Now it won't even crank! :wtf:
 
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