Well, we have progress, but not success yet. I replaced the crank sensor ( and the air filter while I was in there ) this morning.

Now I get the initial relay engagement ( just as before ), and while cranking the relays both re-engage. When I stop cranking, the relays stay engaged for approx 2 seconds, then release. So the PCM seems to be getting all the correct inputs, and doing its job properly.

It seems to be cranking strong still, but does not start. So off to learn how to ensure I'm getting spark, as that seems to be the next place to investigate.

 

Yep, if you have another warm body available, use a pair of INSULATED pliers, to hold the coil wire just above the coil, while your warm body cranks the engine. (I have used my unlicensed grandkids for this exercise..... don't have to be real old to turn a key. ) If you are getting spark, it will jump a small gap, but, not a huge one. Also, the coil packs a wallop, so, make sure that YOU aren't the easiest ground path for the spark.

 

Can I just us a wire, or volt meter to test the spark? The wire coming out of the ignition coil is insulated, and a 90 degree bend, so don't think I can see spark with that cover in place. If I do use a volt meter, will it be a large DC voltage?

 

Something to the tune of 40,000 volts. That should blow your meter up quite nicely.

Pull the coil wire out of the coil, peel the boot back a bit, or, stuff the wire further thru it, so you can see the metal contact, hold it just above the coil, then try what I suggested above.

 

[QUOTE=HeyYou;3554142]Something to the tune of 40,000 volts. That should blow your meter up quite nicely.

Well, don't want that

I picked up a tester at the local shop, and I do not have spark on my old ignition coil nor my new ignition coil. I do get the 12 volts on pin 1, each time the ASR is engaged, and off when it released. So that circuit looks to be working just fine. So I tested across pin 1 & 2 with my volt meter ( and my continuity tester ) and neither are giving me a reading. Something is wrong on the ground side of the circuit. It looks to me from wire diagram, that ground comes from the PCM. So my conclusion is the PCM is not sending ground to pin 2, and so my ignition coil is not being told to turn on from the computer.

Can I ground out pin 2, leaving the coil with constant 12 volts as a test? Or does the PCM send ground each time the coil is to fire off? ( I guess a different way to ask is : Is the coil constantly charged, or does the computer turn it on / off for each spark? )

 

PCM fires the coil by interrupting the ground. The collapsing magnetic field in the primary windings induces current flow in the secondary windings, which generates the spark. If you aren't getting a ground at all, test continuity of the wire between the PCM and coil.

 

This is definitely my next problem. Pin 2 on the coil connector => Pin 19 on the Leftmost cable housing on the PCM. When I test it, I get 2 meg ohms, so we have a really bad connection. I will dig into that bad connection next. Perhaps I disrupted that connection replacing the coil, as my crank sensor was clearly bad, and this would seem to be unrelated. This is why I should stick to working on bicycles.

 

After the initial prime, does the fuel pump/asd relay re-engage when you crank the engine?

 

Yes it does for the initial prime, and when I crank. It stays on for approx 2 seconds after crank too. After testing continuity from PCM to ground on the coil, I now get 100 ohms. I was testing the wrong pin. I would think that is a reasonable amount of resistance. So cabling is not open as I had thought a few minutes ago.

Can I really test that my coil gets grounded ok with a meter, or does the PCM send ground only in short intervals?

 

Ok, so, crank sensor is doing it's job.

I think the pcm only breaks the circuit for milliseconds... so, your meter likely wouldn't even notice..... Test light would probably work, should flash while cranking.