Turns over but won't run

Take the distributor cap off. Make sure the rotor button hasn't broken apart. I've broken 2 in the past 10 years. It will crank forever when that happens.
Still think it's your CPS though.
 
I took off the distributor cap. Looks good to me. I ordered a Mopar CPS from Rock-Auto.

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that sure looks like a lot of corrosion dust . I would change your rotor button and cap. they're cheap enough
 
MOPAR replacement CPS arrived in the mail. Now I need time to replace. Do most people go in from the top or underneath to replace the CPS?
 
MOPAR replacement CPS arrived in the mail. Now I need time to replace. Do most people go in from the top or underneath to replace the CPS?

Ya, get it up on jack stands or something to give yourself space. You can see it easily from the top, but hard to get a tool in there. From the bottom, a long extension with a knuckle and 7/16th socket is what we used...mind you I got my 13 year old to do it, who is half my size.
 
Stock height. No lift. No jackstands. I might just try both and see which works better.
 
Got a chance to work on the Jeep today. Previous owner came over to help hand me tools.

New CPS is in place. Still no start. This time, for fun, I checked the voltage to the coil. The pin near the engine (I assume the ground) has good ground, the other shows 0 volts at rest. When I crank the engine, the hot side pops up to .2 volts.

My best guess right now is the PCM. The coil not getting more volts seems to indicate the coil may not be at fault.

You have all helped with good advice so far. Any more ideas on what to look at next?
 
I went back to read the service manual (I keep forgetting I have this thing) and it has a detailed set of steps to test the coil. It seems to hint that the PCM might not send 12v to the coil if it's not detected. So I need to retest before I start blaming my PCM, I think.
 
CPS = cam position sensor or crank position sensor? Both perform very similar functions and both need to work (among other things) to allow it to give a spark. In my experience, the wiring to the sensors is more often the culprit than the sensors themselves. You can bench test both sensors with a 5V phone charger & a usb/alligator plug. To live test them an oscilloscope is needed.

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This video is for an 02, but other than the cam sensor looking different, it functions the exact same way. Note that the wiring on your 97 may be different from the video, but should match what I have above. (Best thing I ever did was to build a document of all the sensors, the connectors, and the pinouts across all years, so I have stuff like this at my fingertips. )



https://www.amazon.com/dp/B01MY0FG0I/?tag=wranglerorg-20
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My 98 Has the Pickup Coil in the top of the distributor. Not sure how to test it but, I did have to replace that when mine was similar. https://www.oreillyauto.com/detail/...jeep-wrangler?q=distributor+pickup+coil&pos=0


Your picture above does show you also have a pickup coil.

That video I shared shows you how to test it. The sensors look different because one goes on the OPDA and one fits into the distributor, but they both use the exact same mechanism to work the sensor. In fact, if you look at the pickup on both you'll see that it is the same mechanism.
 
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Since the wire from the coil wasn't sparking, I'll not mess with the distributor yet. CPS might be it. I might have to get out my voltmeter and see what I can learn. Not sure I have a small enough probe to get into the plug housing though.



I rotated the relays. No change. I also unplugged the wire on the opposite side of the coil and re-seated it. I'm assuming this is the PCM main harness connection for the coil, but I didn't see another obvious thing to re-seat.

Is there a good way to rule out the ECU? My concern there is primarily because when I turn the key to ON, I get no ammeter or gas gauge readings.

There is an ASD relay (which you verified works) but there is also an ASD fuse (30A). I replaced mine and got my guages back, fuel pump prime and she fired up....still rough, but it fired up.
 
Quite helpful. Thank you.

I'll retest with my OHM rating set per the instructions, but it also seems to indicate that anything except infinite resistance across B and C terminals is a bad CPS.

check your wiring going to your distributor. Also could be ECM
 
Ok, not a lot of time to work on the Jeep this past week. About to go camping again.

I swapped the ASD fuse with the AC and Horn fuses and no change. Horn works, etc. So, I don't THINK the ASD fuse is bad.
I am going to try and test the camshaft position sensor. @hear, that video was promising. I'm going to try something similar. Thank you!

I should probably pick up a cheap ODB at some point. Any recommendations for that for a 97 wrangler?
 
My OBD scanner arrived today! And it cannot connect to the Jeep's ECU. I hooked it up to my truck and it worked perfectly. And, to be more specific, the app on my phone connects fine to the ODB reader and the reader shows power from the OBD port. It tried several different "profiles" and none of them seemed to get any response.

What does this mean? Is my ECU/PCM shot? Are those the same thing?

I also did get some 5v jumpers per the video posted above by @hear, so I may still use that method to just double check the camshaft position sensor.