Some guidance needed

[Scum]

I have a Yukon XL Denali. 200k+ miles. Has been throwing the p0111 code.
I've:
Replaced the cam sensor (multiple times)
Replaced the magnetic actuator (vvt)
Replaced the oil control valve (vvt)
Replaced the oil pickup tube oring. The old one was toast when I pulled it so I really thought this would do it.

Still throwing the code. Oh and it of course throws the traction control light.

Took it to a dealer for checkout. They struggled with the diagnosis. Had to hold it overnight. Came back and said it's a "walking cam" issue and needs a new engine ($8k price tag).

I did some research on walking cam and can find almost nothing about it and literally nothing about it on this engine. Has anyone heard of this? I picture a worn sloppy cam so don't understand why I can't just replace the cams.

With as many miles it has, it's borderline not worth replacing the engine (not that I'd have them do it). So I'm open for any guidance or suggestions you may have.

-Aaron

 

[kbuskill]

I have a Yukon XL Denali. 200k+ miles. Has been throwing the p0111 code.
I've:
Replaced the cam sensor (multiple times)
Replaced the magnetic actuator (vvt)
Replaced the oil control valve (vvt)
Replaced the oil pickup tube oring. The old one was toast when I pulled it so I really thought this would do it.

Still throwing the code. Oh and it of course throws the traction control light.

Took it to a dealer for checkout. They struggled with the diagnosis. Had to hold it overnight. Came back and said it's a "walking cam" issue and needs a new engine ($8k price tag).

I did some research on walking cam and can find almost nothing about it and literally nothing about it on this engine. Has anyone heard of this? I picture a worn sloppy cam so don't understand why I can't just replace the cams.

With as many miles it has, it's borderline not worth replacing the engine (not that I'd have them do it). So I'm open for any guidance or suggestions you may have.

-Aaron

Perhaps it was a typo but P0111 code is for an IAT sensor (intake air temperature)... what does that have to do with what seems to be oil pressure related issues?

 

[swathdiver]

I have a Yukon XL Denali. 200k+ miles. Has been throwing the p0111 code.
I've:
Replaced the cam sensor (multiple times)
Replaced the magnetic actuator (vvt)
Replaced the oil control valve (vvt)
Replaced the oil pickup tube oring. The old one was toast when I pulled it so I really thought this would do it.

Still throwing the code. Oh and it of course throws the traction control light.

Took it to a dealer for checkout. They struggled with the diagnosis. Had to hold it overnight. Came back and said it's a "walking cam" issue and needs a new engine ($8k price tag).

I did some research on walking cam and can find almost nothing about it and literally nothing about it on this engine. Has anyone heard of this? I picture a worn sloppy cam so don't understand why I can't just replace the cams.

With as many miles it has, it's borderline not worth replacing the engine (not that I'd have them do it). So I'm open for any guidance or suggestions you may have.

-Aaron

Welcome to the forum Aaron. What year truck is this? I don't show a P0111 for the GMT900s.

A walking camshaft moves forwards and backward too much, the problem is not caused by the camshaft but by a worn front cover or the spring and button and this was on old Buick engines, not LS motors!

 

[wjburken]

Welcome to the forum Aaron. What year truck is this? I don't show a P0111 for the GMT900s.

A walking camshaft moves forwards and backward too much, the problem is not caused by the camshaft but by a worn front cover or the spring and button and this was on old Buick engines, not LS motors!

A skewed roller lifter due to a cracked lifter guide could put an axial load on the cam shaft. That is about the only thing I can think would even come close to producing a “walking cam” situation. Is your motor making any noises when it is running?

 

[Scum]

Sorry guys. I think I meant p0011. It's the cam sensor code which really could mean anything with the vvt system.

It has a bit of lifter noise when cold. Always has. Same as my other 5.3 motor too. So I've not thought much of it.

I did forget to mention my gas mileage has gone to crap. It's in the 10-12mpg range. Used to be in the 18+ range. Also, it normally pulls a trailer loaded just fine. When I was hauling some wood home it literally barely had enough power to go up a hill. So huge, notable power loss going on as well.

I just got back into town from a work trip so haven't even picked up the Denali from the dealer yet. Most of this is relayed through my wife. So I plan to grill him a bit on why he jumped to walking cam and then to new engine.

 

[swathdiver]

Sorry guys. I think I meant p0011. It's the cam sensor code which really could mean anything with the vvt system.

It has a bit of lifter noise when cold. Always has. Same as my other 5.3 motor too. So I've not thought much of it.

I did forget to mention my gas mileage has gone to crap. It's in the 10-12mpg range. Used to be in the 18+ range. Also, it normally pulls a trailer loaded just fine. When I was hauling some wood home it literally barely had enough power to go up a hill. So huge, notable power loss going on as well.

I just got back into town from a work trip so haven't even picked up the Denali from the dealer yet. Most of this is relayed through my wife. So I plan to grill him a bit on why he jumped to walking cam and then to new engine.

Ok, that code is for the CMP actuator and means the solenoid is showing a low resistance or shorted open. The shop manual shows a number of ways to test this, both with a scan tool (Tech-2) and an ohm meter. Basically, your camshaft is parked and not being advanced which is affecting the engine's performance. If you search back through this forum, I think there were to guys in the last two years that have done this repair.

Dirty or the wrong viscosity oil can cause this code to set, as will a bad battery. Batteries with a bad cell that otherwise pass load tests cause all kinds of headaches for us.

Do you have access to a Tech-2 or other bi-directional scan tool? You can buy a subscription to the shop manual via ALLDATADIY.

 

[Scum]

I don't have access to a tech 2. I have a cheap multimeter only.

I've read plenty on the actuator and vvt. That's why I've replaced all the parts (except the phaser). This problem has gone on through multiple oil changes. It's also why I changed the oil pickup tube o ring because lack of pressure can be a problem.

Reminds me though, I did also change the wiring harness to the actuator and sensor and changed the oil pressure sensor. I did all this work right before heading out of town. While I was on the work trip my wife said the oil pressure was still dropping low at idle which surprised me. That's why I had her take it to the dealer. So maybe a bad oil pump? Or could a walking cam contribute to low oil pressure like bad crank bearings might? (Grasping for straws I know)

I'll also add, I used all acdelco/dealer parts to eliminate the risk of faulty parts. Based on my readings that has been a problem for others on these.

 

[wjburken]

Replaced the magnetic actuator (vvt)
Replaced the oil control valve (vvt)

So you replaced both of the items below?

 

[Scum]

That is correct. Replaced those plus the sensor and the wiring.

Just talked to mechanic. He says it's a bulletin for 07s that the end plates can wear requiring the block to be bored out and oversized bearings used. Still doesn't quite jive for me but he's printing out the bulletin for me to read through.

 

[Scum]

They'll get the bulletin to me Monday. Comment was it's a obscure one.

Comments in the service notes are:
Verifies customer concern, while scanning vehicle on drive test found the fault comes and goes while driving, / GM Tech assistance found camshaft is " walking" an engine causing cam correlation, misfires, oil pressure fluctuations, repair is to replace engine as bearings are pressed into block and labor cost to repair exceed new engine replacement cost.

Anyone able to confirm having to replace cams bearings pressed into block exceeding engine replacement cost?