First problem after one year on 2018 Yukon XL Denali

[_Barry_]

Left an Intro: https://www.tahoeyukonforum.com/threads/new-to-me.147837/

Now for my problem -
Driving back from the coast last week at 75-80 on the interstate my adaptive cruise shut off. When I tried to turn it back on I received a message that it was currently unavailable. It stayed that way for a few minutes and then I notice the check engine light on. The check engine light turned off after 15-20 minutes and I did not notice any issue with gauge readings or driveability.

Stopped for fuel and when I restarted the cruise now operated normally. Maybe 30 minutes later the check engine light reappears and stays on. At idle I hear a ticking sound and can tell their is a slight imbalance. I drove it about 30 more minutes to get home with the check engine light remaining on.

Scanner shows code P302, cylinder 2 misfire. Just as a WAG I replace the coil on that cylinder with a new one, reset the error. On startup the problem remains, ticking sound, slight imbalance feel. The error has not returned so far but I'm not going to drive it until I find it or take it for repair. It may pop the error code again after some set of recycles.

Or not. Possibly the p302 was an anomaly and the real problem is undetected.

Any thought on this? And why did my cruise disengage? Is that a function that occurs when an erro code is thrown?

Thanks for any help!
Barry

Edit: Let it cool back down, restart and threw the P302 code again, so it seems that is the source of the problem. I guess I could change the spark plug just because it's easy on cyl 2. I don't recall the mileage on these, but it's well under the service interval, and they don't typically go bad.
By the way, there is about 160K on the vehicle.

 

[Doubeleive]

plugs and wires book spec is 100k, personally I do them sooner
I would swap plug & wire with another cyl and see what happens.

 

[swathdiver]

Yep, inspect the plugs and wires and wiring to the coil and look for injector leaks on #2. After that, time to look inside and see if the lifter is partially collapsed or if a valve spring broke.

 

[_Barry_]

I'm hoping it's not internal... (don't we all)
The wire from the coil to the plug looked good. I'll do some swapping tomorrow.
Thanks!

 

[_Barry_]

OK, a few days pass by, no luck so I took it to the shop I use when I don't wish to work on a car myself. Bad lifter.

So, options.
#1 - The shop will do the entire job, replace all lifters, valve guides, valve job, head bolts, gaskets, tuneup, etc for $7400.

The last three cars I bought were $6000 each

#2 - Maybe I just do this myself. I can do without the car, I've built many engines over they years, so nothing I can't do.

#3 - find a used engine, replace then I can rebuild the one in it for later

So, not having done much research, what is the consensus on the do it yourself approach? Stock, using stock parts? Replace with mods to eliminate the automatic cylinder deactivation (whatever that is called). Others?

I can do the work, just a question of if I wish to do it. I don't have time right now so it will be at least a month. I have multiple cars I can drive so no issue.

Thanks for any pointers

 

[Doubeleive]

pfft. i would replace the one lifter and drive it....
at $7400 you could put a whole different engine in it and have money to spare

 

[L8T BURB]

$7400 could buy you a 0 miles fully dressed 6.6 liter gas engine AND transmission! Ask me how I know lol!

 

[tom3]

Replace all lifters with stock, disable the AFM. Probably run forever.

 

[_Barry_]

The only problem with replacing one lifter is most of the cost is in the teardown and build back, so might as well at least replace the 8 on that side. Of course if I did it myself the cost to replace one is really low.

Looking at used engines, 5-8K for the most part, depending on miles, plus the installation. Then I have an engine with potential lifter problems. It seems that the lifters in these engines have been a real headache. The odd thing, to me, is that mine is cylinder 2, not one off the cycled lifters.

 

[Doubeleive]

The only problem with replacing one lifter is most of the cost is in the teardown and build back, so might as well at least replace the 8 on that side. Of course if I did it myself the cost to replace one is really low.

Looking at used engines, 5-8K for the most part, depending on miles, plus the installation. Then I have an engine with potential lifter problems. It seems that the lifters in these engines have been a real headache. The odd thing, to me, is that mine is cylinder 2, not one off the cycled lifters.

the price given seems excessive, doing the one side seems more reasonable since it already has 150k on it. My personal issue with it is for a smidge more you could get a reman put in with a warranty, or you could go with a basic repair for now and save up the money for a another engine whenever it decides to go, if it ever does.
doing the one side seems like the best option (middle ground)