New Engine harness, won't run

[MacinTek]

Okay... it's all back together (as far as I can tell) with only two unaccounted for plugs at the firewall.
http://dmctalk.org/attachment.php?attachmentid=36961&stc=1

Here's the real problem, which I don't think has to do with either of those wires. It's probably a common hiccup when replacing electrical in the engine bay but...
I turn the key and all the right noises are made. I twist to start... it turns over, seemingly wanting to start but doesn't. I try again and it just turns and turns. If I wait a couple of minutes and try again, it seems to fire but then stops and the endless turning of the engine resumes without running. Clear as mud?

Any helpful suggestions are appreciated.

[Rich]

Not much help on this one, only a partial answer.

See if the purple-orange connectors will reach to the 2 pigtail connectors coming out of the bottom of the engine diagnostic port. It won't matter if they do but that's where those go on ours.

The diagnostic port isn't important in terms of engine operation.

Red/Black does not look familiar.

[David T]

Okay... it's all back together (as far as I can tell) with only two unaccounted for plugs at the firewall.
http://dmctalk.org/attachment.php?attachmentid=36961&stc=1

Here's the real problem, which I don't think has to do with either of those wires. It's probably a common hiccup when replacing electrical in the engine bay but...
I turn the key and all the right noises are made. I twist to start... it turns over, seemingly wanting to start but doesn't. I try again and it just turns and turns. If I wait a couple of minutes and try again, it seems to fire but then stops and the endless turning of the engine resumes without running. Clear as mud?

Any helpful suggestions are appreciated.

There are so many ways you could have done something wrong there is no simple thing anyone can tell you that can fix this. First of all you should go over all of your work plug by plug. Hopefully you took notes. Then there is the possibility the problem is elsewhere and NOT the harness you just put in. Lastly, maybe there is a problem with the new harness you just installed. The way to start is getting out a meter and following each wire starting with the ignition circuit.

[Rich]

Very much along David T's lines here. We both worked in parallel it seems.

Assuming those mystery wires are not what's keeping it from starting and that it ran before the harness change:

a. You may need to start from scratch.
b. Determine whether you have spark to any of the plugs. Pull a sparkplug wire and check for at least a 1/2 inch spark to a good ground while cranking. If not work back into the ignition system from there. Wiring connections are suspects.
c. If so, determine whether you have fuel. Press the air meter valve down an inch or so and while cranking squirt some starting fluid past it into the intake. If engine fires up on starting fluid but will not run afterward work back into the fuel system.

There are few engine harness wiring connections for the fuel system but if the engine ran before the harness change and nothing else was changed you have to consider it.

[MacinTek]

The harness was replaced because the old one failed... the starter wires (small ones, not big red ones) kept fraying/shorting and frying the starter motor(s). I knew there were a lot of strip-'n'-crimp band-aid fixes done by the clown my father hired to fix it up, so I decided to replace the whole harness with a NOS from DMC.

I did check the connections and they're tight. I know there's fuel at the CIS distributor. The Spark Plugs, Wires, Cap and Rotor are all new. I'll probably replace the coil just to be sure.

[DMCMW Dave]

And you added the two wire links, from the starter to the alternator and the jump start post to the bulkhead? I don't believe it will crank if you didn't, but just in case.

[David T]

The harness was replaced because the old one failed... the starter wires (small ones, not big red ones) kept fraying/shorting and frying the starter motor(s). I knew there were a lot of strip-'n'-crimp band-aid fixes done by the clown my father hired to fix it up, so I decided to replace the whole harness with a NOS from DMC.

I did check the connections and they're tight. I know there's fuel at the CIS distributor. The Spark Plugs, Wires, Cap and Rotor are all new. I'll probably replace the coil just to be sure.


I would not rush to just start replacing parts. You might get lucky but more likely you will just be throwing away a lot of good parts till you accidentally stumble across the problem. And if it IS a wiring problem you will never fix it by replacing parts. At some point (and I think it is NOW!) you need to start diagnosing and trouble-shooting and actually find the problem with some logic. That means getting out a wiring diagram and a meter and checking each circuit wire by wire if necessary. As for the wiring harness, no matter how tattered it was you could have dissected out the bad wires, spliced in some new ones and taped it back up. I have repaired harnesses that were burned and cut up. If you go wire-by-wire and color by color it isn't hard, just time consuming.

[MacinTek]

And you added the two wire links, from the starter to the alternator and the jump start post to the bulkhead? I don't believe it will crank if you didn't, but just in case.

Oh, yes. Big, fat 4 gauge wire from bulkhead to jump post. I was more than happy to avoid 6+ feet of brown spaghetti. I did install the three brown fires between the alternator and the starter... no brainer.

[Lwanmtr]

Okay... it's all back together (as far as I can tell) with only two unaccounted for plugs at the firewall.
http://dmctalk.org/attachment.php?attachmentid=36961&stc=1

Here's the real problem, which I don't think has to do with either of those wires. It's probably a common hiccup when replacing electrical in the engine bay but...
I turn the key and all the right noises are made. I twist to start... it turns over, seemingly wanting to start but doesn't. I try again and it just turns and turns. If I wait a couple of minutes and try again, it seems to fire but then stops and the endless turning of the engine resumes without running. Clear as mud?

Any helpful suggestions are appreciated.


Im having a very similar issue with mine. Still diagnosing, but seems like mine is flooding itself and running (or not rather) too rich it wont start. For mine, I'm
moving onto checking Fuel Distributor and CSV.

As for those two unknown plugs..I have those too, no idea where they go, and the wire combos dont show in the diagram. Plus, I have an extra red bulkhead
connector (not connected to anything) that serves an unknown purpose.

[Jonathan]

Im having a very similar issue with mine. Still diagnosing, but seems like mine is flooding itself and running (or not rather) too rich it wont start. For mine, I'm
moving onto checking Fuel Distributor and CSV.

As for those two unknown plugs..I have those too, no idea where they go, and the wire combos dont show in the diagram. Plus, I have an extra red bulkhead
connector (not connected to anything) that serves an unknown purpose.

Someone else not long ago just mentioned those. I assume it is the same thing you're talking about and there are two of them because one is for automatics and one is used for manual transmissions. The automatic connector, among other differences, is the one with more wires on it. Post a photo to double check we are talking about the same thing, or see if you/we can find that thread again. The original poster on that thread was having trouble with the transmission and computer governor, which turned out to be electrical because his car had the wrong bulkhead connector plugged in (the one for a manual trans had been used mistakenly).

[cis6409]

The 2nd plug in the picture the one with the red and black wires coming out, I think that plug is the" loom connection" for the cold start valve and or thermo time switch connectors.
Not the actual connections to the valve and thermostat time switch but where they join up with the rest of the loom to go back to the bulk head connector I mean ..


The other plug is with the Orange/purple wires is Definitely the diagnostic port connections

Cheers
Shane

[MacinTek]

The 2nd plug in the picture the one with the red and black wires coming out, I think that plug is the" loom connection" for the cold start valve and or thermo time switch connectors.
Not the actual connections to the valve and thermostat time switch but where they join up with the rest of the loom to go back to the bulk head connector I mean ..


The other plug is with the Orange/purple wires is Definitely the diagnostic port connections

Cheers
Shane

Is this the item you're referring to? What is it and where might it be?
http://dmctalk.org/attachment.php?attachmentid=36975&stc=1

[Bitsyncmaster]

Is this the item you're referring to? What is it and where might it be?
http://dmctalk.org/attachment.php?attachmentid=36975&stc=1

That is a capacitor. It's not on all cars (mine did not have it). It's mounted near the idle switch plate if the car has it.

[MacinTek]

Okay... I found one connector on the old wire harness that I don't recall seeing on the new one. From the connector, one black/blue wire goes to the to the solenoid valve, the other black/blue wire goes to the bulkhead; the thicker, black wire, I assume, grounds somewhere. Was this eliminated in newer wire looms?

http://dmctalk.org/attachment.php?attachmentid=36976&stc=1

[MacinTek]

Furthermore... after consulting the wiring diagram (courtesy Adobe Illustrator), it appears that I've found that it connects between the aforementioned capacitor, the vacuum solenoid and the idle speed switch. Question is... is this what might be causing the car to crank but not start?

http://dmctalk.org/attachment.php?attachmentid=36977&stc=1

[82DMC12]

Okay... I found one connector on the old wire harness that I don't recall seeing on the new one. From the connector, one black/blue wire goes to the to the solenoid valve, the other black/blue wire goes to the bulkhead; the thicker, black wire, I assume, grounds somewhere. Was this eliminated in newer wire looms?

http://dmctalk.org/attachment.php?attachmentid=36976&stc=1


Hey everyone, I'm currently doing a frame-off restoration and I found this thread which asked the same question I had. The answer is YES the blue/black and black 2-pin connector connects to the black/red connector on the firewall. I found an older engine bay photo of mine where it is clearly connected together. Counter intuitive, yes, but it's true! Just wanted to help the next person out.