Jeep YJ has no spark: Anyone recognize these connectors?

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Dmiz88

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Having some trouble with my YJ

So my long term project is finally somewhat together. I took a 88 tub and nose and put it on a 94 running gear. I inherited it when a friend moved and had no way to take it. When I got it it was time to put the tub on and switch the dash to make the wiring all work, so what I did was change everything over to the 94 harness. Nothing was cut, it should be mostly plug and play. After putting everything together and trying to start it I have no spark. No voltage to the connector for the coil, also i did not hear any fuel pump and built no fuel pressure, when I check the voltage at the connector for the sending unit it read 7.5v however there was over 12v at the fuel pump fuse. I am new to jeeps, I've worked on lots of equipment and other vehicles but not too familiar with jeeps, is there anything quick I should check?

Second question does anyone recognize these connectors I cannot find anywhere to plug them in. Also of you have any Input, I'm all ears.

The large square block looks pretty corroded like it was not used before and the small, what I'd refer to as weather pack connector has about 2 feet of slack and it's on the passenger side toward the top of the firewall.

The second picture, that connection is also on the passenger side towards the alternator.
I know it's hard to diagnose through

text and pictures but I figured it was worth a shot, to ask people who are more familiar. I just can't wait to get it going and today was a bit of a let down

IMG_20200413_190059.jpg


IMG_20200413_184820.jpg
 
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I'm in the process of installing my 2.5L and hokking up all the wires so I have almost everything labeled.

The two in the lower picture might be for the air conditioning. It requires both type connectors. I have the small one tie wrapped to a wire bundle on the firewall and the large block is an empty spot in the weather proof box.

The top photo might be for the oil pressure sending switch because of the location but my 92 looks slightly different and only has one wire.
 
Yes I believe your probably right, I asked another group about the large block and they were thinking auto transmission connector. Mine is a standard so that may be true as well. I guess I'm just trying to eliminate any thing I may have not hooked up but after going thoroughly threw the harness connections, I'm not thinking that is the case. Time to do more digging
 
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  • Dmizzy88
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    Registered UserJoin: about 1 hour agoPosts: 2
    3 minutes ago· #1

    Having some trouble with my YJ

    So my long term project is finally somewhat together. I took a 88 tub and nose and put it on a 94 running gear. I inherited it when a friend moved and had no way to take it. When I got it it was time to put the tub on and switch the dash to make the wiring all work, so what I did was change everything over to the 94 harness. Nothing was cut, it should be mostly plug and play. After putting everything together and trying to start it I have no spark. No voltage to the connector for the coil, also i did not hear any fuel pump and built no fuel pressure, when I check the voltage at the connector for the sending unit it read 7.5v however there was over 12v at the fuel pump fuse. I am new to jeeps, I've worked on lots of equipment and other vehicles but not too familiar with jeeps, is there anything quick I should check?
    Second question does anyone recognize these connectors I cannot find anywhere to plug them in. Also of you have any Input, I'm all ears.
    The large square block looks pretty corroded like it was not used before and the small, what I'd refer to as weather pack connector has about 2 feet of slack and it's on the passenger side toward the top of the firewall.
    The second picture, that connection is also on the passenger side towards the alternator.
    I know it's hard to diagnose through
  • text and pictures but I figured it was worth a shot, to ask people who are more familiar. I just can't wait to get it going and today was a bit of a let down
View attachment 115561

View attachment 115560
Click to expand...
The big one is for a relay for an automatic transmission torque converter clutch. Not needed on a manual. The harness just dangles.

The two-pin plug next to the relay plug should be for an under hood light. Check to see if it’s hot with a test light with the key off. If it is, it’s your hood light for sure. The hood light itself is probably long gone. They tend to fall apart and that point owners often remove them.

The two pin over by the alternator is either for the 4WD indicator light, or the AC drier high/low pressure switch. It looks like the 4WD plug I snipped off of mine, but it looks to be coming off of the harness that is typically for the AC compressor and drier, so I need more clarification from you before I could say for sure. I can take some pics of mine and see if you have my style of drier plug, if you do then that would confirm that the one in question is for 4WD and not AC.

However, I can promise you none of them are for ignition or spark. Is the crank position sensor in good shape?Maybe swap in a known good one?
 
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