TJ turns over but won’t start

Would that account for the flip/flop of having voltage on the opposite wire?
Ok so I dig some digging since I got on my computer. 1997 TJs use a different pinout than 1998 and up. Ironically, the pinout for the 1995 YJ is the same as 1997.

1995/early 1997 plug pinout:
  1. 5 Volt Supply
  2. Sensor Ground
  3. Camshaft Position Sensor Signal

Late 1997/1998 plug pinout:
  1. Camshaft Position Sensor Signal
  2. Sensor Ground
  3. 5 Volt Supply

If you're having flip-flop voltage, then my guess is you have the wrong sensor installed. If you're using your original PCM, put in the old sensor from your old motor, and I'm guessing your computer will be able to read it and sync it with the crank sensor. Let us know how it works out when you get home!
 
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Hey thank you very much. I will try that when I get home and let you know. You know, every time I work on my Jeep, I want to punch a Jeep engineer! lol!
 
This really sounds like a good line of reasoning because, if we look back at the chain of events, you could start it with your previous distrib but it would then do a 180 (still puzzled by that one). But, since you got the replacement distrib, it has completely refused to kick over. It just stands to reason that it's the distrib somehow.
 
How do you reset the ECM? Is that the remove the battery cables and touch them together thing?
Yes. Removing just the negative lead for a few minutes will do it. Removing both leads and holding them together just speeds up the reset process. Removing one lead plus turning the headlight switch on does the same thing more easily with the same speed. It discharges the little capacitors inside the PCM that keep its adaptive memory alive which serves to reset the computer.
 
Gentlemen,
Tworely, Jamison C and Jerry were correct. As soon as I put the original distributor back in i am now getting 12.39 volts on the green wire and 0 volts on the white wire same as the battery voltage. Timing is at #1 on TDC on the combustion stroke. I put in a new coil and I am now getting spark. It still wont start. Looks like it is going to the professionals tomorrow! TJ Hunnicutt The part about the distributor was my fault. I installed it on TDC exhaust stroke and thought the distributor had jumped a tooth. I was frustrated and confused and shouldn't type on the internet when in that condition. I removed the battery cables as Jerry suggested and will check it again in the morning. Good night Jeeping world.
Thanks for everyones help! It was much appreciated!
 
Best of luck on the morrow. Be sure to go back through all the things you touched to verify they are now correct. I'm betting something else you worked with is just off somewhere and you're within spitting distance of making it purr.
 
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I just wanted to say thank you to everyone for their advice and suggestions, on getting my TJ running. Here is a quick overview of what happened. This happened over a 6 month period and the no start was from the beginning of January. What a way to start the year out!
Well, what an ordeal the last six months have been. It all started last year when I thought I had a head gasket leak because I saw antifreeze leaking down the side of the block. Off came the head and to the machine shop for a complete rebuild. I got the head back, installed it and there is the antifreeze leak again. Long story longer, I have a cracked block. Noe the search for an engine. I finally went with Timbuk 3. While I was waiting for my new engine, I decided to clean the engine bay. That Jeep hasn't been that clean since it rolled out of the factory. My engine arrived and I installed it without too much fuss. It fired up the first time. I ran it for about 10-15 minutes following break-in procedures. all of a sudden it started to miss, I shut it off and checked everything. I went to start it and it would just crank. It is now January and I have read every forum article, watched every YouTube video that dealt with crank, no start conditions and I asked a lot of questions. I'm sure everyone got tired of that. I even got a FSM and followed the diagnostic procedure. I sur wish I had a scanner! It is now February! I have given up and sent it to my mechanic. He now has no hair, from pulling it all out. I finally got it back on Friday. Here is what got replaces. Crank Position Sensor, Cam Position Sensor, fuel pump, Rewired the harness from the CPS (broken wire). For a whopping total of $1300.00. When I got it home it still had a miss and code P0300 and P0305. I decided to change the plugs and plug wires and wall la, she's alive and running great! Thank God that's over! I'm ready to have some fun!
Thanks to everyones suggestions and help! I very much appreciate it!
Igoo65
PS by the way, If anyone needs a newly rebuilt 4.0 head with about 25 miles on it, I have one for sale! 719-641-9257.
 
@Igoo65 did you figure this out? I’m in serious need of any help. Same situation
I just saw your message. I probably not going to be much help, but I at least wanted to respond. When I finally got my Jeep back from the original mechanic, I was still having mis-fire issues. I found a new mechanic at Car Worx here in Colorado Springs. He had it 3 hours and had it running correctly. He told me that he had to manipulate the distributor as his partner cranked it over. He said they locked it down checked the timing with a Snapon scanner. It has been running fine after that. Sorry that probably isn't much help. Generally if yours isn't starting, the first thing to look at is the crank sensor. That is usually is the culprit. Always use Chrysler parts. They are more expensive, but you can get bad parts from regular parts stores. Good luck.
Igoo65
 
@Igoo65 thank you! Just saw this, seriously same problem for me. Perfected the timing and boom! She cranked (with some gas). Throwing signal for weak camshaft position sensor signal to the pcm but it’s wong tong bs. I learned my lesson. ALWAYS use mopar sensors. Runs strong now when she starts over. Will be saving up for the mopar sensor. Problem solved!
 
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