How to change your OPDA

There are other threads about the newer sensors throwing codes in cold weather. I have seen a couple people claim that the more recent Crown sensors are good but I have not seen enough of those to have any confidence. If you use good google-fu, you can probably find some fairly lengthy discussions on the topic.
 
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Carter6 said:
Interesting, so it may be the cold after all? I’m not sure if the sensor I have is OEM or not. Is there a way to tell?
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The sensor in your picture looks a lot newer than the OPDA. Can't tell for sure but throwing codes when cold is the main symptom of all the new sensors I tried. An original, OEM (old) sensor fixed my problem and countless others with the same issue.
 
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g.hayduke said:
The sensor in your picture looks a lot newer than the OPDA. Can't tell for sure but throwing codes when cold is the main symptom of all the new sensors I tried. An original, OEM (old) sensor fixed my problem and countless others with the same issue.
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I think you’re right seeing as it didn’t throw a code today. At least I’ve got an OPDA now for when mine does start to fail. I take it the best place to look for an OEM sensor is eBay? Do the new Mopar ones work ok?
 
I tried a new Mopar sensor and it threw codes when cold. I have heard some say that the newer Crown sensors are good but I can't confirm or deny that.

The only old sensors I have found are on eBay when I search on the original OPDA part number. I bought 2 old OPDAs just to get the sensors (now I have a spare). There are not many on eBay and the 2 I bought both came from Israel, even though the ad said they were in Italy.

You might also try daveysjeeps.com or jeepsunlimited.net. They both part out Jeeps and should have some old sensors. One of those 2 sites told me they have good luck with new Crown sensors but YMMV.

If you get an old sensor, I think you'll be good to go as long as your cam is still good. Replace that OPDA ASAP.
 
Here's a tip for some who are putting off replacing this unit.

I had mine go bad on me yesterday (angry monkeys sound). I'm in a fairly metro area (Tampa Bay region), and nobody, and I mean NOBODY, carries this part in stock. The closest I could find was an Advance that carries the Dorman version, and even then, they couldn't guarantee delivery next day. Anybody who was able to order one wanted at least $130 for a version that wasn't even the Crown (NAPA wanted > $150 for their OEM version). Even my local dealership said that they stopped carrying the MOPAR version back in 2015.

Eventually, I was able to find the Crown OPDA on Quadratec for about $100 (Extreme Terrain had the same part for about the same price, but they don't give an option for next day shipping). So even with the expedited shipping, it still cost me less than local sources, and got here much sooner, only a couple of hours ago.

Also, I don't recall if it's been mentioned in this thread, but it still bears repeating. All of the replacement OPDAs, even the Crown, have been known to have issues with the cam position sensor. If you're not throwing any CPS codes, you're better off using the one that's already in the Jeep. Hang on to the new one as a spare, but all of the ones that come with the OPDAs seem to have an reputation for not lasting very long (3-6 months in some cases).

So as far as the OPDA goes, you're better off saving money, ordering the right part online ahead of time, and put it in before the monkeys come, especially if you're near or above that dreaded 100,000 mile mark, which most TJs are.
 
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@Chris. I changed my OPDA out last week and all went well. Then I changed my oil today and noticed I only drained 4.5 quarts. I checked the OPDA area and noticed leaking. I forgot to install the tiny gasket. So I found it and SLIPPED THE OPDA out just enough to slide it on. Then tightened it down. Now it won’t start. It will turn over and almost start, but won’t. Could I have slipped it back in in the wrong position? If so, How do I get it in the right position now?
 
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JMT said:
@Chris. I changed my OPDA out last week and all went well. Then I changed my oil today and noticed I only drained 4.5 quarts. I checked the OPDA area and noticed leaking. I forgot to install the tiny gasket. So I found it and SLIPPED THE OPDA out just enough to slide it on. Then tightened it down. Now it won’t start. It will turn over and almost start, but won’t. Could I have slipped it back in in the wrong position? If so, How do I get it in the right position now?
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If it turns over and won't start, it could be a sensor issue. Did you knock the sensor loose by chance or anything?

If it was a timing issue (which can happen when installing a new OPDA), generally the vehicle will start, but it will run very poorly. Unless the timing is off enough that it won't even start. If that's the case, everything has to be set to TDC again and properly timed. I believe there is a section in the FSM for this, as I've never actually had to do it.
 
Chris said:
If it turns over and won't start, it could be a sensor issue. Did you knock the sensor loose by chance or anything?

If it was a timing issue (which can happen when installing a new OPDA), generally the vehicle will start, but it will run very poorly. Unless the timing is off enough that it won't even start. If that's the case, everything has to be set to TDC again and properly timed. I believe there is a section in the FSM for this, as I've never actually had to do it.
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Ok, I read the FSM manual. It says the housing has to be at the 4 o’clock position from the right side of the engine. When I went out and looked at mine it was at about 5 o’clock position. So I rotated it and fooled around with it many times and got the jeep to start. When I get to what I think is the sweet spot it is still throwing codes p016 and 0344. The start is pretty good, not what it was before, but it pretty much starts right up with just a slight roughness.

The only picture I have of the OPDA before I took it out is showing it at a different orientation than now. Is it possible to put it back in in the wrong orientation and the Jeep still start?

I know this pic sucks, but it’s all I got from yesterday before I removed it (and working flawlessly)

80974

Now
 
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JMT said:
Ok, I read the FSM manual. It says the housing has to be at the 4 o’clock position from the right side of the engine. When I went out and looked at mine it was at about 5 o’clock position. So I rotated it and fooled around with it many times and got the jeep to start. When I get to what I think is the sweet spot it is still throwing codes p016 and 0344. The start is pretty good, not what it was before, but it pretty much starts right up with just a slight roughness.

The only picture I have of the OPDA before I took it out is showing it at a different orientation than now. Is it possible to put it back in in the wrong orientation and the Jeep still start?

I know this pic sucks, but it’s all I got from yesterday before I removed it (and working flawlessly)

View attachment 80974
Now
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Yep, I think you got it to where it will start, but I think the timing is now off unfortunately. It doesn't have to be off by much either, all it would take is a little bit to make it run poorly.
 
Here is what you need to do:

1.) Remove the top cover on the OPDA and observe the hole in the disk. There is a hole in the housing that this hole will get aligned with. Find a drill bit or something that is a good fit in the hole and have it available for step 3.

2.) With a socket and large ratchet or breaker bar, turn the crank by hand until the timing mark on your harmonic balancer is aligned with the TDC pointer on the motor. If the hole in the OPDA is 180 dgrees from the housing hole, turn the crank another revolution and align the marks again. This brings your #1 piston to TDC on compression.

3.) loosen the bolt on the OPDA and rotate it until the hole in the disc and the hole in the housing are in perfect alignment. Use the drill bit to make sure they are aligned.

4.) Tighten the bolt on the OPDA being careful not to turn the OPDA and put the cover back on. You're done but make sure you did NOT leave the socket on the crank.
 
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Started to hear the laughing monkeys last week. Replaced my OPDA today and followed the video. Fired it up and so far so good.
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A little wear on the gears, hopefully I caught it before it got to bad.
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Overall, it's an easy part to replace, if you're patient and don't get frustrated easily working in tight spaces. The biggest tip is just take your time and work like the tiniest of details matter (which they do). DON'T RUSH IT.
 
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I have an ‘04 that’s new to me, PO said the engine was swapped. My opad is different than those pictured in this thread, can anyone identify this one?
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