After a few years of mostly trouble-free driving, my wagon apparently dislikes the East Coast.

Since getting here, I started experiencing an intermittent problem - after the car had warmed up, the ignition would intermittently die. (Factory installed tachometer would dive straight to zero, no power or response to accelerator pedal.) The car wouldn't 'stall' until speed dropped off far enough, and sometimes, she'd kick back in with a hard jolt, tach shooting back up, power coming back. She'd die both from being idled for ten minutes or in the middle of an eight hour drive intermittently. I've checked all the wires under the hood, I think, all the continuity seems good, resistance at the distributor and coil seem good, I have power at the coil, and the module, plugs are new, spark plug wires are new, distributor cap and rotor are new, coil's been replaced, swapped in a used ignition module, checked the grounds. Putting a new Bosch coil in gave me a pair of good weeks, but then the problem came back - including a drive down I-95 from New England to Philly with only one stall at the very end, but the next time I tried driving her, she made it ten minutes and died. Towed home, nothing would get her started. Still dead in the garage.

Aside from going over all the wires in the ignition circuits again, is there anything I'm missing? I've got the Bosch ignition system, N/A B21 head on B23 block (this involved a bent crankshaft on the original engine), automatic transmission, GLT wagon. She cranks, the plugs get wet with fuel, but there's just no spark, including checking for spark at the coil lead to the distributor, so I'm pretty sure it's something before that in the ignition - but as I understand it, the distributor also sends a signal to the ignition module to trigger the spark in the first place?

Well, now it has a multitude of new problems... (Lambda-sond and CIS system both not working) but it runs. Pick-up coil replaced, it fired right up.

Sure sounds to me like an oxidized connector. How are those on the ballast resistor?
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Art Benstein near Baltimore

The quickest way to double your money is to fold it and put it back into your pocket

Weather's getting better, so I can get back to this - no obvious corrosion at the terminals, wires seem to have continuity, and I found a copy of the ignition green-book.

Following the fault tree, I've gotten to two things I can't figure out in it.

It says to check for earth at Terminal 31 on the ICU, but it then says 'Terminal 31D is not earthed' as the follow-on part of the tree. I've got power at the two wires it says I should

Am I checking Terminal 31, the ground through the mounting of the ICU, or Terminal 31D, which goes to the pick-up coil?

If I've not got ground there, where's my next step?

(Also, it says 'check for arcing to earth at pick-up coil' - how do I do that? Would a failing pick-up coil equate to the symptoms I've been having?)

Sounds like you have a different troubleshooting chart; one with a British accent. Maybe something is lost in the translation.

Tell you what: the appearance of corrosion is not necessary for electron-inhibiting corrosion to exist. Visual inspection is not enough. Also, with the currents necessary in the primary circuit, ohmmeter continuity checks may fail to find poor connections. My troubleshooting tree recognizes this and uses the voltage drop method of locating a poor connection. Internally, 31 and 31D are the same part of the module circuitry, so an adequate ground (zero volts on the terminal under load) will result in the proper ground at 31D unless the module itself has a bad connection inside of it.

Check the chart in these notes I made on the breakerless ignition to see if it makes more sense than the British version. http://cleanflametrap.com/breakerless.htm

End game suggests something simple. I just recently read a thread where a savvy professional tech asked the poster "you did not crank the engine with the dizzy cap off, did you?" and sure enough, the problem in that case was caused by the cap clip falling into the distributor and bending the reluctor rotor. And I've fooled myself with the connector pin push-back.


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Art Benstein near Baltimore

After eating an entire bull, a mountain lion felt so good he started roaring. He kept it up until a hunter came along and shot him. The moral: When you're full of bull, keep your mouth shut.

The symptoms described sound like classic distributor coil failure--first intermittent conking out---restarting when cooled a bit. Eventually total failure.
The coil itself is easy enough to change--the tricky part is getting to it. The reluctor is held in place with a snap ring and then must be pried off. Be careful with this part - the reluctor fits tight and can bend easily. It is positioned by a TINY steel pin which slides into a slot formed by a groove in the distributor shaft and the inside of the reluctor -- don't lose the pin. One time I found the pin to have totally disintegrated from rust. Proper orientation of the reluctor is essential.
OOPS! -- for some reason my first post did not show up when I checked on it after being called for a "semi emergency" (tantrum) with our 2 year old granddaughter--I thought maybe I didn't hit "submit" -- hence this 2nd post--now the first showed up. That's just the effect I have on computers :-) --Dave

The description of symptoms make sense, and it seems to be where I ended up in my fault tree tracing; now, before I rip this apart, or push it down the street to my local mechanic (literally)... where can I find a replacement coil? I thought I'd seen them on IPD once, but they don't seem to be there anymore.

If after having checked and cleaned all the connections in the ignition system it sure looks to me as though the problem lies in the pick up coil. Typical symptoms are intermittent loss of spark as the motor heats up -- return of spark with cooled motor. Repeat of this scenario until final loss of spark.
Not having experienced this in many years I went through all the connections on my '75 B20F distributor powered '69 144S while returning from a track day at Pocono Raceway last fall. Stuck on the shoulder of I-80 it restarted and would drive a short distance before conking out again after going over connections (no doubt working again due to cooling rather than cleaned connections). Luckily it failed a final time while on the downside of a 7 mile grade and I was able to coast into a PA rest area. I found it was possible to sleep sitting upright overnight :-) !! In the morning I retrieved the original points and condenser distributor packed deep in my "spares" box.
I'm not sure why - but in the mid-late '80's while working in an indy Volvo shop I replaced these failed coils on a number of cars -- but haven't (except for mine) since then. Replacing the coil is straight forward - only the retaining snap ring and reluctor can be tricky as the reluctor is positioned with a TINY solid steel pin inserted in a slot formed by a groove in the dist. shaft and the inside of the reluctor - don't lose it. On one car I found that pin to have completely disintegrated by rust. -- Dave

Good call Dave. Pickup coils like this one would fail at the ends of the enameled wire where it transitions to the cable connections, and the failure would be triggered by and follow the temperature induced expansion and contraction. The symptoms (intermittent open coil) would exactly mimic the push-back in the connector in my example, but not have the ingredient of being caused by me.
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Art Benstein near Baltimore

One must wait until evening to see how splendid the day has been.

hello art ben- always a pleasure to talk to you. regarding the very varied issues one has to deal with in the 240, you seem to follow one of my precepts taught to me by uncle moe. first check for air , gas and spark. second check the simple stuff first. your reference to checking oxidized connectors and the ballast resistor connections is an excellent example . which connectors would you check on the 240 other than the battery terminals. corrosion there is as common as cockroaches in stinking creek. where is the ballast resistor on a 92 245. these checks over 40 years saved me a lot of f bombs when my slant six dodges marooned me at the creek. actually would carry a ballast resistor spare with me all the time in the dodge days. when i got my 245 in early 11, it started running like hell. checked plugs- ok , wires ok , distributor cap and rotor pretty well burned up- replaced, end of problem until this week. running rough like a miss especially when cold . feels like a gas or air problem . plan is to recheck plugs, check air filter. wondering about that big fuel filter under the floor on the fuel pump (not the in tank one). gut instinct is air or fuel starvation. dont want to take off that fuel filter unless i have to. heard that job can be hellacious. would appreciate your insights. hope youre not freezing in md. 83 here. thanks tons oldduke