Wires to coil pack

Hi everyone. I have a 94 Jeep YJ Sahara. I have been having some ignition problems. A few months ago the engine would turn over but was getting no spark. I replace the coil pack, and it fired right up. however while driving the next day it just stalled while I was cruising. I pulled over and played with it for a minute and got to start back up. and this is what it's been doing for the last few months. Last night I was unable to get it to start and so I started messing with the wiring and found that the wires going to the connector that go to the coil pack we're kind of torn up and shorting out a lot, which is what I figured what's going on anyways. Today I trace those wires to where they go, and I spliced in a new wire using 16 gauge wire and crimped with the red wire connectors, and covered with shrink tubing. I use my multimeter to check for continuity and both wires seemed good all the way to the connector, however I am still not getting any spark. I talked to a friend who said that it could be because my gauge of wire is too low and using the connectors instead of soldering is causing too much resistance that is being detected by the computer. I'm going to solder in some 20 gauge wire tonight, but wanted to post this and case that did not work. Does anyone have any other suggestions as far as what could be causing the problem? Thank you

 

20 awg wire will be smaller than the 16 awg so if your friend it correct that would make the issue worse. You will want to go the other way, something like 10 or 12 awg, whatever size the factory wiring was (or larger).

Welcome from Oklahoma.

 

The original wire inside the harness appears to be around a 20 gauge. The smallest thing I had was a 16 gauge. My understanding is that bigger gauge wire allows the current to flow easier because of less resistance. I'm not sure if my friend was saying changing the gauge of the wire mid wire was the real problem or if it was the crimp style connectors that I used. In any case I bought some 20 gauge wire today and am going to solder the lines tomorrow.

I'm honestly not sure where these wires actually go to. I simply Trace them further up the wiring harness and replace that section. One of the wires is green with an orange stripe and it looks like it went along the passenger fender and goes to a connector by the fuse box with a lot of other wires. The other wire is a light gray and it goes up among the engine block and goes into the plastic housing that holds all the wires that connects to the fuel rail.

 

I'd focus on what damaged the original wires and what was shorted out. Not sure swapping to 20ga wire is the solution as that wire is way too light-duty.

 

Well again, the original wires that I'm replacing are about a 20 gauge. They are the very lightweight wire that goes to the connector that plugs into the coil pack, and goes off into the wiring harness. I'm not talking about any of the heavy duty wires like the ground wire that connects to the bracket on the coil pack, or the main coil wire that goes to the distributor. Just the small light gauge wire on the connector that plugs into the coil pack. They weren't torn up too badly just had a little Nick's here and there from being old and brittle. I spliced new wires to replace those and am still getting no spark from the coil pack. Tomorrow I will solder my wiring instead of using a crimp connector and see if that makes a difference.

 

Correct.. but 20 is smaller than 16.

 

Okay let's assume the wire guage has nothing to do with any of this. It comes out of the harness as 20guage, I spliced in 3 ft of 16guage and then spliced back to the 20 guage where it meets the connector. I used crimp connectors.

Before I did this, it cranked up fine, although it was misfiring badly because the wires were grounding out due to Knicks in the insulation. The last thing I did was turn off the engine, disconnect the battery and spliced in these wires, now I have no spark at all.

The question is do you guys think this has to do with resistance in the line as my friend suggested, or do you think there is something else going on? Does anyone know where these wires actually go to?

 

This is what I see on the wiring diagram. I'm usually fairly good at reading these but this one is confusing. Not sure what the grey wire is going to or what those numbers are. The green and orange wire seems to go to a couple other places like the brake lights?

 

The Dark Green/Orange wire provides power and goes through the ASD (Automatic Shut Down) relay. This is why that same wire goes to many different components, when the ASD is deactivated it will shut everything down.
And that may be the case here, easiest thing would be to swap the ASD relay with a known good relay.

 

So today I soldered the original wires back together and shrink tubed them to avoid any shorting or arcing. Still no spark. My friend suggested looking inside the distributor. The rotor is bad but he said the pick up was more than likely bad. Going to test it with tye ohm meter Tomorrow.