OPDA failure, need to replace CPS too (options?)

zwhite1999

Just Empty Every Pocket
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Ontario, Canada
Drove 600 miles yesterday in a new-to-me 05 LJ with 113k miles. Ran great! This morning I go outside to start it, and I get the dreaded laughing monkeys. Time to do the OPDA!

I looked online and noticed the Crown unit is the best replacement, so I ordered on on Amazon and it will be here tomorrow. So far, I am struggling to remove the old one.
First off, I snapped the plastic part of the CPS that goes to the mounting bolt, so it's no longer able to be bolted on. I assume I will need to replace the sensor. I also am struggling to remove the sensor, it feels as if its really wedged in there. I put my whole weight into it and I can't get it out. Google searches tell me if you can't get OEM, NAPA Echlin is the next best option. Would Part #: UNI CSS634 or Part #: UNI CSS1159 be better?

I am also struggling to remove the 13mm bolt on the mounting bracket below. I only have a standard 13mm wrench, no flex head. I ordered a flex head, but is there a way to get it out otherwise with a standard 13mm socket or wrench? Couldn't seem to get a bite on it.

Does anybody have any tips for doing this job in the driveway with minimal tools? I left off after aligning the pinhole with the hole on the original OPDA to indicate TDC. I just have to remove the CPS & get that mounting bolt off.
 
The Crown unit will come with a cam sensor. Just try that. If it doesn’t work, then you can try to find a Mopar cam sensor.
 
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For whatever it may be worth, here's my particular OPDA story:

https://www.doubleveil.net/jeep/twenty-eight.htm

Thank you for this!

A distributor or offset box end is best. And it's a 1/2 in (12.7 mm) not 13 mm.

Hose it down with PB Blaster, etc.

I managed to get the bolt out with a box end wrench. It broke free very easily, surprisingly. No PB, and engine had been off all day. I was SHOCKED.

The Crown unit will come with a cam sensor. Just try that. If it doesn’t work, then you can try to find a Mopar cam sensor.

I am gonna leave the Crown one in, and see what happens. Otherwise, I am picking up a NAPA Echlin sensor tomorrow from the store. I've heard good things about those. I haven't been able to source a Mopar CPS yet.
 
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It's possible that neither the Crown nor the Echlin sensor will work right. Not because either is bad, but because they are slightly different from the Mopar one, and will require a slight adjustment.

Unfortunately, it takes a bidirectional scan tool to read the cam/crank difference, which you need to adjust the OPDA. Those tools range from $100 for a slow, cruddy one to $350 and higher. And many of them require a hefty subscription payment each year. You might get lucky by turning the OPDA in tiny increments one way or the other to arrive at something which will run well.
 
It's possible that neither the Crown nor the Echlin sensor will work right. Not because either is bad, but because they are slightly different from the Mopar one, and will require a slight adjustment.

Unfortunately, it takes a bidirectional scan tool to read the cam/crank difference, which you need to adjust the OPDA. Those tools range from $100 for a slow, cruddy one to $350 and higher. And many of them require a hefty subscription payment each year. You might get lucky by turning the OPDA in tiny increments one way or the other to arrive at something which will run well.

Is there any way to salvage the broken CPS? The mounting bolt part snapped off, because the plastic was brittle.
 
It's possible that neither the Crown nor the Echlin sensor will work right. Not because either is bad, but because they are slightly different from the Mopar one, and will require a slight adjustment.

Unfortunately, it takes a bidirectional scan tool to read the cam/crank difference, which you need to adjust the OPDA. Those tools range from $100 for a slow, cruddy one to $350 and higher. And many of them require a hefty subscription payment each year. You might get lucky by turning the OPDA in tiny increments one way or the other to arrive at something which will run well.

Mark the OPDA to the block before making adjustments. I bet you could get it without the tool but would take some systematic testing.
 
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