This should be simple, but...

PROJECT: 1996 Civic LX, D16Y7 (1.6L SOHC).

SYMPTOMS: No-Start. Very weak spark. TEC distributor. New rotor, new cap, new wires (verified at around 5K ohms/foot), new OEM NGK plugs.

OBSERVATIONS: Constant and solid 12.8V to the distributor (drops to about 10.8V on cranking). Fuel pump runs prime cycle on ignition power-up and when reference pulses are generated. Injectors being pulsed. Both phases of position sensors (below the plate in TEC distributor) signals are good. CMP (on top of plate in TEC distributor) signal is good. Coil primary is 0.74 ohms, secondary 16K ohms. "Ignitor" is getting solid ground, good 12V source (blue wire), and according to the scope is receiving good signal from the PCM and is switching the coil reliably. With the distributor removed and hand operated (spun) the coil produces good spark. With the distributor installed, cap/rotor removed, and engine cranked the coil produces good, healthy blue spark across a 2.5mm gap. With the rotor and cap installed and engine cranked, individual spark plug terminals have unreliable and weak spark, sometimes barely lighting a neon spark tester.

I'm presuming (perhaps errantly) that the Main Relay is functioning properly since the fuel pump runs, PCM has power, and injectors and ignitor are getting signal.

I've verified TDC on #1 via a crude TDC checker method, and verified rotor position to correlate. I've verified the 1-3-4-2 firing order numerous times at both ends of the wires.

Any ideas?

Well, nothing "simple" is easy. The switching module ("Ignitor" in Honda-ese) was suspect, but still switching. Testing on the bench revealed a failure after some heating. Upon researching the problem, and discovering that even though they are somewhat failure-prone, it was a bit surprising to learn that no one stocks one locally.

Enter the GM HEI switching module:

http://www.wwdsltd.com/files/HEI-Module1.jpg

A few screws to remove the failing "Ignitor"

http://www.wwdsltd.com/files/HondaTECDistributor01.jpg

Whereupon there was a realization that working on it while it was still stuck to the back of the head was ludicrous. Four wires were added to extend the OEM connections to the switching module (Hitachi power Darlington in a fancy case):

http://www.wwdsltd.com/files/HondaTECDistributor02.jpg

Fitting the interior cover/wire shield and rotor back into position:

http://www.wwdsltd.com/files/HondaTECDistributor03.jpg

Altering the bottom corner of the distributor cap to accept the harness extension:

http://www.wwdsltd.com/files/HondaTECDistributor04.jpg

Cleaning off and flattening a good heat sink/ground point for the HEI module (an even bigger Hitachi or Motorola power Darlington array):

http://www.wwdsltd.com/files/HondaTECDistributor05.jpg

And slapping it all back together so that this thing is outta here...

I ended up removing the cap, rotor, wire cover and ignition coil so I could drill/tap the holes for the module without destroying the coil (hint to any of you doing this). Sorry I didn't get "after" photos, but I was glad just to see to leave as soon as possible.

Apparently, I'm not the first to understand the advantages of this:

http://www.mx6.com/forums/showthread.php?t=101723

http://www.clubprotege.com/wil/howto/hei/index.htm

http://zhome.com/ZCMnL/tech/hei.html

Among many others.

FWIW, the Honda 30130P06006 "Ignitor" wholesales for around $130, and none of the couple dozen parts houses I called stocked one. That's not counting the chain stores like AutoZone, Murray's, O'Reilly, Advance, etc. However, the GM 4-wire HEI modules sell for between $12.99-$22.99 depending upon where you shop, and I could have bought 200 of them today within a ten mile radius.

Nice question-turned-write-up. Good info. :bigthumb:

It'd be nice if everyone posted questiosn as coherently as that.

Well, unfortunately...

That didn't work out all that well. Evidently, the TEC coil used in the Honda/TEC distributor doesn't like the extra current capacity of the heavier switching module. The car cam back with a horrendous misfire, and there is a nice black hole being burned in the back of the coil (the side which faces the metal cover) . Either the coil was already starting to short and that took out the original "ignitor" and the Delco HEI just switched right through it, or the extra current capacity has caused enough secondary spark voltage and energy to find a weak spot in the epoxy insulation. I suspect the former, since the area on the coil cover next to the hole in the plastic coil is already rusted. I've replaced the coil and it's running fine now.

I'lll be certain to post back if it happens again, but I'm guessing it will be fine. I just wanted to warn any other potential retrofitters of the situation.