Cam Position Sensor O ring

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Blk00ss

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Does anyone know if you can do just the ORing? I’m sure you can, but not sure of O ring size, or if there is one made specifically for this. If so, do you have a PN?

I’ve use Mahle seals in the past, but can’t seem to find one for this application. Our cam sensor is fine except I’m pretty sure we have a slow leak coming from it. I know this because just last week I did valley pan gasket, knock sensor gaskets and new knock sensors as well as Fel Pro aluminum manifold gaskets. Oil pressure sensor was also just changed 3 weeks ago. Took some pics and it appears to be slightly wet right near sensor and of course it’s the one thing I did not replace during last repairs
 

MassHoe04

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Time trying to figure out what is needed to just replace the O-ring, you might be better off just buying a new sensor.

I don't even see a separate O-ring that comes up.

GM Genuine is only $45 at RockAuto.com...

NAPA has Echlin for about $70, which is a good substitute for electrical timing/ignition stuff.

Myself... I would probably just ignore the leak, if everything else is fine.
 
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Blk00ss

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Time trying to figure out what is needed to just replace the O-ring, you might be better off just buying a new sensor.

I don't even see a separate O-ring that comes up.

GM Genuine is only $45 at RockAuto.com...

NAPA has Echlin for about $70, which is a good substitute for electrical timing/ignition stuff.

Myself... I would probably just ignore the leak, if everything else is fine.
Yeah, I could do the sensor. It’s not hard. Was just curious if an o ring could be replaced since our sensor is fine. It seems CPS o rings are available for many other vehicles. Find it hard to believe one wouldn’t be available for 5.3
 

MassHoe04

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Yeah, I could do the sensor. It’s not hard. Was just curious if an o ring could be replaced since our sensor is fine. It seems CPS o rings are available for many other vehicles. Find it hard to believe one wouldn’t be available for 5.3
I am just gun-shy on things like those sensors... I tend to not want to mess with something critical like that unless absolutely necessary. Especially, if the sensor has the engine running nicely.
 

OR VietVet

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Make sure your local parts store(s) have a good o-ring collection kit(s) and just match it up. If they have the sensor in stock, they could go to kit and find a match.
 
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Blk00ss

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I am just gun-shy on things like those sensors... I tend to not want to mess with something critical like that unless absolutely necessary. Especially, if the sensor has the engine running nicely.
Right!

I’m the same, which is why I’m wanting to attempt an ORing versus new sensor. However, I see some people asking if a re-learn is needed. I’ve changed CPS in other vehicles, and I literally start it right up with no issues when done. Don’t really understand people saying re-learn is needed

Also…I do order quite a few parts from RA. I like their site and I feel there info is correct. But honestly after paying their shipping charges, I find lots of times I could buy the same part locally for about the same once all said and done.
 
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OR VietVet

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Right!

I’m the same, which is why I’m wanting to attempt an ORing versus new sensor. However, I see some people asking if a re-learn is needed. I’ve changed CPS in other vehicles, and I literally start it right up with no issues when done. Don’t really understand people saying re-learn is needed

Also…I do order quite a few parts from RA. I like their site and I feel there info is correct. But honestly after paying their shipping charges, I find lots of times I could by the same part locally for about the same once all said and done.
Since I use Genuine GM or AC Delco parts, 99% of the time, the RA price, even with shipping is cheaper than the same parts as dealer and would not want to compare to less expensive aftermarket parts. Plus, there are 5% discount codes for RA, here at this forum. The wait for the part to be delivered can be a PITA at times and sometimes, the parts store is it, but hell, I can even get at Amazon cheaper than parts stores too, for those same GM parts.

Instead of doing an o-ring, I agree with @MassHoe04 and say do the whole part.
 

Fless

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However, I see some people asking if a re-learn is needed. I’ve changed CPS in other vehicles, and I literally start it right up with no issues when done. Don’t really understand people saying re-learn is needed

You've been fortunate. A relearn isn't always necessary when replacing either (or both) the crank or camshaft position sensor, but it's highly recommended. Not doing the relearn can sometimes cause intermittent or unexplained misfires, so it's a good practice to have the relearn done at some point soon after.
 

MassHoe04

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I had my battery on the 04 Tahoe disconnected for a few hours and when I started it up, it sputtered, stumbled and ran really rough for a few minutes. Scared me for a few minutes, I thought I really screwed something up.

The ECM must have worked though its own re-learn as the computer continued to collect more data from the CPS and other sensors... adjusted timing, fuel delivery and spark. Then, it smoothed right out.

If data from a new replacement sensor is "close enough" for the computer to get away with making only slight adjustments to get things running within programmed parameters, then it would not throw any code and pretend nothing happened.

Continued misfires are probably not good for the engine, so a forced relearn on a new sensor might be better than just leaving the computer to figure things out on its own while it misses and skips. Seems like it would be easy enough with the Tech 2.
 

oldchev

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What is involved for a "re learn"?
Do you have to have a Tech2? The shop manuals (GM) don't say anything about such a process.
I would love to hear the what and why for this.
I would think (by old school standards) that stopping on #1 TDC and removing the CMP it would work.
 

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