Failing OPDA in pre-2005 4.0?

bromel

bromel

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I've got an occasional chirp coming from my 2000 4.0 with 100k. Assumed it was a pulley until I used a stethoscope to narrow it down to the OPDA cover. That seemed odd to me, considering that as far as I know, only the 05 and 06 model years had OPDA issues. Has anyone heard of these going bad for older model years? Anyone know the correct part number?
 
I just replaced mine and made a writeup here with the part number, wrench sizes, and torque values.

In my case, there was no noise. There was too much lateral play which trashed my sensor and caused CELs. I'm sure it would have begun making noise before long.
 
On the 2000-2004 models it wasn't referred to as an OPDA. It was called something else, I just can't seem to recall. I'll bet @MX952 knows what the technical name is.

However, don't believe the bullshit that just because yours is a 2000 it can't have any issue. ANY MECHANICAL MOVING PART WILL FAIL IN TIME, and yours is no different. Take yours out and inspect it for wear. Post pictures of it if in doubt.

You only hear about the 05-06 OPDAs since they had a higher rate of failure. However, earlier models can have the same problems and are not immune.
 
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RMETeeJay said:
I just replaced mine and made a writeup here with the part number, wrench sizes, and torque values.

In my case, there was no noise. There was too much lateral play which trashed my sensor and caused CELs. I'm sure it would have begun making noise before long.
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This is a great writeup, thank you. I'm not throwing any codes, but it looks like I have the same problem.

Chris said:
On the 2000-2004 models it wasn't referred to as an OPDA. It was called something else, I just can't seem to recall. I'll bet @MX952 knows what the technical name is.

However, don't believe the bullshit that just because yours is a 2000 it can't have any issue. ANY MECHANICAL MOVING PART WILL FAIL IN TIME, and yours is no different. Take yours out and inspect it for wear. Post pictures of it if in doubt.

You only hear about the 05-06 OPDAs since they had a higher rate of failure. However, earlier models can have the same problems and are not immune.
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You're right; it's called the camshaft synchronizer in pre-05 model years.
 
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bromel said:
This is a great writeup, thank you. I'm not throwing any codes, but it looks like I have the same problem.
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I hope it will be useful to you. If you can remove your fan, you can probably save time over the way I did it because I had to turn the crank a tiny bit at a time from underneath.
 
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Just for posterity, replacing the the camshaft synchronizer fixed my squeak. It sounds just like a failing pulley, but if you use a stethoscope you can hear it coming from below the camshaft position sensor. Better I replaced it now before it seized up and detonated the engine.
 
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bromel said:
Just for posterity, replacing the the camshaft synchronizer fixed my squeak. It sounds just like a failing pulley, but if you use a stethoscope you can hear it coming from below the camshaft position sensor. Better I replaced it now before it seized up and detonated the engine.
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Great work! Glad to see you complete the circle on the thread and fix your issue. Good to get it fixed at the first sign of noise due to it's critical nature. While the name is different and the design is a bit different, they are essentially the same thing in the 2005-2006. They are just more durable on the 2000-2004 models from what we have seen historically. The OPDA\Camshaft Synchronizer shaft is driven off the camshaft via a gear-to-gear connection. The OPDA\Camshaft Synchronizer shaft also has a bushing that it's internal tone wheel spins upon and so the housing can be stationary as it turns. If the bushing begins to fail, the shaft will start to wobble and cause wear on the gear-to-gear camshaft connection. The softer metal should fail first on the OPDA\Camshaft Synchronizer gear, but that is only a failsafe for short term protection, not long term negligence.

Meanwhile, the camshaft sensor monitors the tone wheel from it's position on the OPDA\Camshaft Synchronizer housing. If the shaft wobble is severe enough, it can throw off the camshaft sensor's ability to "read" the tone wheel indexing pegs because of the "gap" change as it spins (it is a Hall-effect sensor). When the signal loss happens during the wobble/gap issue, the PCM will error with a CEL and code P0344 (Camshaft Position Sensor “A” Circuit Intermittent). If the wobble is really severe, the tone wheel can even hit the tip of the camshaft sensor head. The wobble is generally worse at extreme code startups, at certain engine RPM's , or in extreme heat conditions where the wobble can get just a little bit worse than in other conditions.

TL;DR - like you did, folks should definitely heed the warning when noise is found or thought to be coming from the OPDA\Camshaft Synchronizer. If making noise, it is likely causing wear on the camshaft gear.
 
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On the 05-06's, the OPDA is known to damage the camshaft before it makes noise or throws codes. in these years, its recommended to proactively replace it, but keep the wiring from the stock jeep. The Crown is the best aftermarket part and is under $100. There are some good videos on youtube with tips to get the TDC holes lined up prior to removal and install tips.
 
Interesting. I wasn't worried since I have a 2003.

Is there a mileage limit where you should just replace it on general principles?
 
I believe you only have to be proactive and worry on the '05s thru '06s. Prior to '05 it was a different design that did not have the issues
 
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John L said:
I believe you only have to be proactive and worry on the '04s thru '06s. Prior to '04 it was a different design that did not have the issues
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05 and 06 have OPDA. 04 and older have different design which is a camshaft synchroniser and not OPDA (camshaft synch and oil pump drive assembly).
 
WallyWest said:
Interesting. I wasn't worried since I have a 2003.

Is there a mileage limit where you should just replace it on general principles?
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You need to be vigilant about the 05 and 06 OPDA units because it's not a question of if, but when, they begin to fail. The camshaft synchronizers on older models tend not to fail, but as my experience shows, they do sometimes need to be replaced.
 
This cracks me up.

I replaced both of my jeeps OPDA because of this forum.

There was no sign of uneven wear on the old part gears.
 
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I have a 2005 wrangler x with the 4.0 L engine. After sitting for a year, I started it and got no oil pressure. I pulled the pressure sensor, while running, nothing came out.
Could it be the OPDA or oil pump?
Have I damaged the engine starting it 5 or 6 times running for a total of 5 minutes?
 
reidmj77 said:
I have a 2005 wrangler x with the 4.0 L engine. After sitting for a year, I started it and got no oil pressure. I pulled the pressure sensor, while running, nothing came out.
Could it be the OPDA or oil pump?
Have I damaged the engine starting it 5 or 6 times running for a total of 5 minutes?
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