Chasing misfires on driver’s side (4,5,6)

[Quiker]

I continue to have misfires on 4,5,6.
The truck cannot hold boost, makes boost then somehow cycles up/down.

I’ve return almost everything to stock as part of the troubleshooting - no luck. Recently pulled the intake manifold looking for any leaks, swapped all the things that attach to the manifold - the fuel regulator, the mess that is the brake booster ( and stuff) , the PCV and line - I didn’t swap the map sensor at the back of the intake - thinking it would affect all cylinders.

Is there a way to check the cam phasing? Assuming if there is something off on the side - it would affect those three cylinders and not the others.

 

[Quiker]

Update - turned out that the problem was.... a clogged catalytic converter on the driver's side.

 

[Braden]

Wow how did you figure that out

 

[Quiker]

Wow how did you figure that out

I was only throwing misfires on the driver's side bank - 4,5,6 - swapped plugs, tested coils. Then looked at all the hoses and tubes that were hanging of that side of the intake. Once through all that - I was either dealing with a cam/cam phaser issue - or something common to those three cylinders - and downstream. led me to the cat.

If you pop out the O2 sensor between the turbo and cat - I was building pressure there - which led me to believe it was clogged.

 

[EricM]

You say "clogged cat".

Was it melted, or was it actually clogged with some type of debris or carbon?

There is nearly always an underlying reason when a cat fails. Keep an eye on that bank.

 

[Grant]

I have the same thing happening to my 18 right now, been liked it since last Saturday and in the shop since Monday morning 3 days now. Purhaps I will give the dealer a heads up to help them out. Thanks

 

[Grant]

Continued

 

[Donovan]

I feel for ya'll I have had misfires on all of my high performance vehicles, EVER.

Each e46 m3, e92 m3, Audi r8 and this truck. They are tough to narrow down and are almost always something simple and less than 200 bucks.

Except for the fking Audi r8. lol.

 

[Grant]

One other question that I may have failed on diligence. Is it possible if I failed to drain my catch can could it have been full and sucked everything back in through the engine to possibly clog that catalytic converter if that's what my problem is or have caused all the other problems misfiring. Normally I drain it quite religiously and I've always only found a very small amount in there. I am now in a very cold winter environment and my truck is not inside due to where I'm working. Full tank of fuel on at Monday did a 500 km Journey on Saturday and this is when it happened. Also my girlfriend used my truck throughout the week and she very excessively idled it to keep it warm? I am not a guy that idles excessively. Anything related to these things. Mine seems so similar to the gentleman who created the post. Quiker

 

[Dachuri]

I am having a similar issue on my 2017 that my dealer has denied warrant work due to my grill shutters being removed (3 years ago). Curious how this turned out?