I didn't realize it quit running after a period of time after you grounded the wire. Having to ground the computer side of that cut wire to get it to start is a pretty good indication that your problem is a loss of ground feed somewhere. The ground probably backfed through the first PCM and fried it, so don't try it with your new PCM.

At this point I would focus on each and every black wire going to the PCM to make sure they're making connection.

 

Just for grins, I stuck the old computer in. That sucker might still be good! The clock came up on 12:00, the fuel pump came up, the engine turns over (still no spark, but it's the same thing with the replacement). I did the "on-off" thing with the key and the only thing it said on the odometer was "P done" which might mean code "P" and done checking, or "this P(cm) is done (for)". What do you think? It was just starting the afternoon monsoon, so I didn't want to risk getting water in the replacement computer's connections. I'll put it in tomorrow when I get a chance and read it's codes. Thanx, Spence.

 

I checked for codes on the replacement computer. " P done" was all it put up. I checked all of the black wires I could find at the computer connectors. Actually the black plug was the only one that contained any black wires (with stripes). I checked for continuity to ground, using the head of the screw that connects the small black and the small black with the pink stripe to the firewall. Measured resistance from the negative battery cable terminal to this point (contacting bare metal on the firewall) is 0.0 ohms. From this point to the black female connector at the computer, I read: top row, far right, 2 black w/tan (I think) = 0.0 ohms, top row, pin 24, black w/green stripe = open, middle row, pin 15, black w/red (I think) stripe = open, bottom row, pin 4, black w/blue stripe = 0.0 ohms and a beep for a split second - then open (checked 3 times to verify, did the same thing each time). The white and the grey connectors had no black wires. I was using a Fluke 337 digital multimeter to do this. The plugs are in good shape with no signs of any corrosion. Their fit is tight. All of the wires going into the plugs are secure and tight. Any thoughts on how to procede? Thanx, Spence.

 

Wow, this is going to end up being a "one for the record books" solution once it's found. I can't get it out of my head that the ASD relay isn't powering up. That's going to be the "smoking gun" to get to the solution. Since you're getting code responses from the PCM it's safe to say it has at least partial power. The PCM does have multiple power feeds going to it. I don't know, maybe one of them is dead while the others are working?

 

Ordinarily, most people wouldn't be too happy about their vehicle throwing a code. Today, mine did and I'm thrilled! Why couldn't it have done this a week ago?! I looked on-line to identify it, but every site I went to skipped right past the number. I'm getting "P 0351", which I'm assuming is a bad coil or coil connections, as the P 0350, P 0352 and up are coil codes. Since my van only has one coil, I'm making this assumption. Anybody? Thanx, Spence.

P.S. - I'm already aware that I'm not getting power to the coil, I'm just happy that, at last, the computer recognises that there's a problem.

 

P0351 Ignition Coil A Primary/Secondary Circuit Malfunction.

This code can be set when the battery is no good. How old is the battery and what's it's present charge condition? Perhaps charging it overnight and then bringing it in for testing would be prudent.

 

Hey, Alloro,

Man, I wish it was that! However, the battery I use is a marine dual purpose (Start/House) deep cycle, group 27 with about 100 amp/hours capacity. It's only a couple of years old and is well maintained. I can literally crank for hours with it (or until the starter burns up). I'm convinced that the problem lies somewhere in line from the #87 output of the ASD relay on circuit A142, probably between the #16 output of Joint Connector No.2 and the coil, most likely at or after S(ideloop?) 123, which powers the injectors. I know they're working because, when I crank the motor, atomized gas puffs out at me through the open #5 sparkplug hole. Remember, the problem manifests itself as no 12VDC at the coil primary positive, and I have 12VDC at the #87 output of the ASD relay. Your thoughts? Thanx, Spence.

 

If you have +12v at the #87 relay terminal but not at the coil, then there is a bad splice or a break in the wire running from the ASD relay to the coil.

 

My mistake, Alloro! I got screwed up by looking at the schematic on the side of the relay instead of the numbers of the pins (terminals). Actually, I have power at 30, 85 and 86, but NOT at 87. I have continuity from the #87 female connector to the dark green w/ orange stripe at the coil, but when I turn the key on, I get no voltage there. I've substituted every relay I have (I've got three extras), but the results are the same. Any ideas? Thanx, Spence.

 

After work today, we're going to winch it up on a car hauler and bring it back to the hacienda where I can concentrate on it. Wish I could get it started and drive it up the ramp. It'd be way easier than come-alongs with the weight of the beast + 1/2 ton of racks, tools and wire!