2014 GM 3.6L startup clatter and cam phaser confusion

[Woodsnut]

I have a 2014 Chevy traverse 3.6L with 208k original motor, chains, and phasers. I have always kept the oil clean and full. Car runs and drives perfect, no CEL or other running issues, idles smooth as butter, and plenty of power.

Around the 180k mileage mark I started to notice a 2 second clatter on startup, only if the car had not been started in 30mins or more.
My research pointed to a worn locking pin on the cam phaser, more research found multiple Toyota and ford owners had the same clatter and drove them that way for 50k+ miles with no issue. So I figured "leave it be just drive it"

Fast forward to current day cold start in Wisconsin with temperature at -5F. I got the normal clatter and well as the engine running rough and missing for 3 seconds after startup, after 3 seconds misfiring was gone and car runs perfect. It has done this twice now only when the temps are roughly below 0F.

I have a few (lots) of questions I cant seem to find the answer for:

1) What is the life expectancy of the cam phasers after the lock pin is worn?
2) If the phaser fails, what actually happens inside the phaser that causes failure?
3) If the cam phaser fails somehow will it leave me stranded?
4) Is the below 0F misfire related to the cam phasers (and actuators) taking a long time to "zero out" because of thick oil?


Appreciate any info!

This car has been so great to me and has logged 15K+ miles pulling a 5x8 trailer with dirt bike and gear, super reliable, comfortable to sleep in, never been stranded it just keeps going.

 

[JavierH19]

Some members reported the start up rattle going away with a better filter or thicker. Also it might be the tensioners losing pressure or the cam phaser as the sound is similar. Maybe post the sound when it's cold. It making the rattle only after 30 or so minutes makes me believe it's the tensioner slowly bleeding down more so than the phasers as those will have startup rattle again in 10 seconds or less from what i've read.

There are many threads like these. This is a recent one for a different engine but it's the same principle. I too have heard that they can last a long time doing that. I've read on honda forums that some went another 100k+ with the rattle and nothing happened but it's best to try to not make it rattle if possible.

O

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• Okis14
• Replies: 4
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

• 

 

[Wylie6G72]

My sister-in-law had a 2013 Equinox 2.4 that sounded like a thresher at startup. She eventually got the check engine light for something related to cam position, and took it to the dealership, where she got all of her oil changes done per the maintenance minder. She ended up getting a new timing set, but she had been driving like this for more than 2 years. The 2.4 and 3.6 are infamous for stretched chains and worn or broken guides, allegedly caused by extended OCI. Part of the repair for her car was to reprogram the maintenance minder for more frequent oil changes.
You'll probably be okay for a while, but remember what's on the horizon.

 

[MalibuRam65]

My sister-in-law had a 2013 Equinox 2.4 that sounded like a thresher at startup. She eventually got the check engine light for something related to cam position, and took it to the dealership, where she got all of her oil changes done per the maintenance minder. She ended up getting a new timing set, but she had been driving like this for more than 2 years. The 2.4 and 3.6 are infamous for stretched chains and worn or broken guides, allegedly caused by extended OCI. Part of the repair for her car was to reprogram the maintenance minder for more frequent oil changes.
You'll probably be okay for a while, but remember what's on the horizon.

Hopefully with new API SQ oils out not now these timing issues comes to a minimum.

 

[Oillover]

I've read on honda forums that some went another 100k+ with the rattle and nothing happened but it's best to try to not make it rattle if possible.

+1
"Rattle" long enough and your engine will lose timing.
Then you'll be left with a hefty repair bill for a reman/new engine.

 

[melk]

I have an early 3.6 in my 08 CTS with 63k which I hope will go for a long while still before I need to worry about the chains. No rattle and the coldest starts are in the 20s. I did have an odd no-start condition the other day where I had to pump and hold the gas to get it to fire up. First time it’s ever done that, not entirely sure what that was about.

 

[Woodsnut]

That usually signifies a flooded condition as fulll throttle cuts the injectors. Check the purge valve selenoid on the front of the engine, its a $20 part and easy to replace. If its clicking its shot