• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

Loss of Stabiltrak/traction control/flashing SEL and P0304 all happened at same time

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
2011 AV 225K miles. Filled up with 87 octane in morning. Leaving work was fine, got to 1st intersection, was still rolling and quickly pulled a hard right turn onto 4 way road.
I hit the gas while turning and immediately, SES came on flashing, DTC then showed stabiltrak and traction contol needed servicing. I plugged in and read P0304. Engine went immediately to very rough, and acted like it was on 7 cyl.

Yesterday, pulled out all 8 plugs, replaced them (looked real bad, iridium looked like burnt off and like 0.060" gap, although had been in only 6 months), still same code for the #4 plug. Still rough, and cannot clear the stabiltrak & traction control stuff. Swapped #4 plug wire and ignition coil with the #1 on drivers side and no improvement.

Wondered if had bad fuel and had affected at least 1 injector so put injector cleaner in tank. Idled for an hour, drove today to and from church (30 mi round trip) and still no improvement in roughness or these stablitrak things.

Weird how it all occurred at once. I wonder if some wheel sensor got hinked up or the sensor cable unplugged or wire sliced when it when around the corner...?

Looked at all 4 ABS sensor cables, and the TC sensors, nothing damaged or out of place.

At a loss on how to proceed as a DIY.
 
Last edited:

ygmn

This is a Custom Title
Staff member
Administrator
Moderator
Charter Member
PM 2022
PM 2021
PM 2020
PM 2019
PM 2018
PM 2017
PM 2016
PM 2015
PM 2014
PM 2013
PM 2012
SM 2011
SM 2010
SM 2009
SM 2008
SM 2007
SM 2006
SM 2005
SM 2004
SM 2003
Full Member
Joined
Jan 17, 2002
Messages
35,128
Location
Bourbon St. Balcony

BainMan

Full Member
Joined
Mar 22, 2019
Messages
864
Do the rest of the normal misfire troubleshooting including compression, YGMN sent a good link... Seems like you've got a good start on the list already.

Cylinder 4 is part of the AFM cylinder deactivation system. Do you have a lifter ticking? Maybe a new tick or louder noise than before? If so, pull the rocker/valve cover and check the lifters. A couple videos for reference:
 

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
Local shop says #4 lifter is hung up. They refuse to replace the AFM lifters on Avalanches, saying that they stopped doing it on Avalanches because it never stops the AFM problem.
They will only install another engine and they found one with 114K on it and will install it for a mere $7700 with 90 day warranty.
Any one interested in a nice LTZ, 225K, 1 year old rebuilt trans and 4 like new Michelin Defender tires (20" diameter LTZ stock chrome wheels_Sunroof, excellent leather, DVD.....? RUST FREE, purchased in NC and titled here in Bedford VA (no salt used on my local roads!).
 

ygmn

This is a Custom Title
Staff member
Administrator
Moderator
Charter Member
PM 2022
PM 2021
PM 2020
PM 2019
PM 2018
PM 2017
PM 2016
PM 2015
PM 2014
PM 2013
PM 2012
SM 2011
SM 2010
SM 2009
SM 2008
SM 2007
SM 2006
SM 2005
SM 2004
SM 2003
Full Member
Joined
Jan 17, 2002
Messages
35,128
Location
Bourbon St. Balcony
go to another mechanic... they sell kits to remove AFM by changing lifter and cam and program.

Or get it fixed and use AFM computer to turn it off.

Many repairs out there..
 

EXT4ME

PM 2022
PM 2021
PM 2020
PM 2019
PM 2018
PM 2017
PM 2016
PM 2015
PM 2014
PM 2013
PM 2012
Full Member
Joined
May 3, 2012
Messages
4,907
Find another mechanic.

AFM deletes are done all of the time.
 

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
Update after last night praying to the Lord about what to do:
This morning, Same shop (former GM dealership) offered to change out the 4 AFM lifters (with current 2021 design) and provide warranty.
I presume that these 4 are all the intake lifters, not exhaust ones.

Work will be completed by Wednesday @~16% of the replacement engine cost.
So, I can decide whether to continue with the AV, sell outright or as a trade-in.

So, a guy says that my AV blowing blue clouds upon cold startup is most likely not ring issue, but that it's been proven that replacing the drivers side valve cover with 'new style' PCV valve will stop any oil draining back down overnight and resting on the piston head whereby that oil gets burnt off on cold starts. Thoughts?
 
Last edited:

EXT4ME

PM 2022
PM 2021
PM 2020
PM 2019
PM 2018
PM 2017
PM 2016
PM 2015
PM 2014
PM 2013
PM 2012
Full Member
Joined
May 3, 2012
Messages
4,907
The updated driver's side valve cover addresses an issue where there is too much oil laden bypass crankcase air being drawn into the intake manifold and then passed through to the combustion chambers.

These engines do not have the old conventional PCV valves of the old days.

Instead, there is a baffle of sorts mounted on the inside of the valve cover to meter the amount of crankcase air being drawn into the intake to be burned in the combustion chambers.

Looks to me the old design may have allowed too much oil laden air to be sucked into the engine at any given time, therefore the redesign.

I do not know if the valve cover on my 2004 EXT is the new or old design, but here is a picture of mine after I took it off and cleaned it up.

IMG_4148 (Small).JPG

In the picture, you can see the PCV baffle riveted inside the driver's side valve cover.

Intake vacuum draws crankcase air in through the hole in the baffle to a port located on the top of the valve cover back toward the driver's side of the firewall.

The updated valve cover possibly changes the size of the hole in the baffle to better meter the crankcase air going into the intake to be burned.

Here is a picture of the passenger side valve cover, which does not have an updated version.

IMG_4150 (Small).JPG

You can clearly see the oil fill port on that cover.

The port on the passenger side valve cover attaches to a hose that mounts near the throttle body to provide clean air to be drawn into the crankcase.

After cleaning, both covers received new Fel-Pro gaskets before reinstallation.
 

CenFL Avalanche

Full Member
Joined
Aug 16, 2014
Messages
139
Taking my 2007 Avalanche to the shop on Thursday. Same issue. Stab and Trac lights come on, engine sputtering and stalling at stop sign. Thought is was gas, but going to have my mechanic look everything over.
 
Last edited:

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
To EXT4ME, you may have a point there, however; looks like the 2011 AV with the AFM stuff, don't look the same as your nice photos.

To CenFL Avalanche, I'm picking my AV up tonight, its all done. The technician said that those stabiltrak and traction control idiot light messages are normally the response to the P030x misfire. My initial code was for P0304 the # 4 cylinder.
Had them also replace the oil pressure sensor and the screen below it and to use only an AC Delco unit.

Will post again after doing a R/T to work and back tomorrow. :)
 

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
Have about 100 miles after the lifter work. A mix of low speed in town, and highway speed, and so far, it runs like a new engine.
My dash display usually showed 17-18mpg on regular route to work and home again ... now, displays 19-20ish FWIW.
No idiot lights, and car is smooth as silk.

So far, it hasn't gone fully into 4 cyl mode in areas that is used to do that. So, I thought it briefly did, because I saw the oil pressure rise up but I was not on the display mode which would have indicated the AFM was now in 4, not 8.

I first thought the techs had deleted the AFM and put in regular intake lifters like what would have been in cylinders 2,3,5&8, but I doubt that happened, especially as mileage seems to have increased.

Tech noted on paperwork that they removed a lot of carbon, but did no say where it was found...I use additives to clean injectors, but is there something else I should use to prevent carbon junk?

OH, while the techs were in there, they replaced the passenger side head gasket and used 2 gallons of coolant, so perhaps there was a burned area around that #4 cylinder and coolant was being burned too.

$1,400 repairs vs $8,000 for a used engine with 114K on it and no history.

Engine now has 226K, shop did an oil change, used bulk 5w-30 full synthetic....i would have used syn blend because of the mileage.
 
Last edited:

CenFL Avalanche

Full Member
Joined
Aug 16, 2014
Messages
139
To EXT4ME, you may have a point there, however; looks like the 2011 AV with the AFM stuff, don't look the same as your nice photos.

To CenFL Avalanche, I'm picking my AV up tonight, its all done. The technician said that those stabiltrak and traction control idiot light messages are normally the response to the P030x misfire. My initial code was for P0304 the # 4 cylinder.
Had them also replace the oil pressure sensor and the screen below it and to use only an AC Delco unit.

Will post again after doing a R/T to work and back tomorrow. :)
Good feedback on the stabiltrak and traction control misfire. My mechanic who I have used a long time found no codes or nothing else to be concerned with. After that visit I decided to replace the plugs since it's been 80K or so miles. Normal plug wear. I then put in some 3M fuel cleaner and Shell 93 premium gas. Truck ran fine for two weeks. Then this week, I've had a strange occurrence each morning at roughly the same location. I go to the first traffic light from my house and about 125 feet from making a right onto the next road, it hesitates slightly. Then it runs normal like nothing happened. This happened each morning this week. Today on the way home, my low oil pressure light came on and went off just as fast. I replaced that sensor about 5 years ago. Wondering if my situation is more ECM related?
 

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
So, after around 500 miles, this kitten just purrs.
I hadn't mentioned this, but the first times I would start the engine (either cold start, or warm start) the P0521 (low oil pressure) code would pop up. I would reset it while still driving and it would not return until the next startup. The engine was acting like new, smooth as silk and no clattering noises so I figured this was just a false alarm code.
Over the next week as the miles racked up, the code just stopped appearing, and I would notice the AFM switching to 4 cylinders would happen often, which is something that only rarely happened in the 2 years I had my AV.
Maybe its acting like it should.
Also, my oil burning and subsequent needing to add oil at least once a week has stopped completely.
No oil burning at all, no burnt oil aroma out the tailpipe either.
Goina keep this car.
 

CenFL Avalanche

Full Member
Joined
Aug 16, 2014
Messages
139
My Range AFM disabler is on order and will cease the cylinder deactivation and allow it to run in V8 mode full time. One less thing to be concerned about.
 

Toggenburg

Full Member
Joined
Sep 26, 2021
Messages
18
Any stories about using a

Range AFM/DFM Disabler, without changing cam or AFM lifters???

 

Vaeagleav

PM 2022
PM 2021
PM 2020
PM 2019
PM 2018
PM 2017
PM 2016
PM 2015
PM 2014
PM 2013
SM 2006
SM 2005
Full Member
Joined
Jun 4, 2004
Messages
5,382
Location
Tidewater Virginia
My Range AFM disabler is on order and will cease the cylinder deactivation and allow it to run in V8 mode full time. One less thing to be concerned about.
Remember to follow the instructions about unplugging the device if you park your AV for several days since it puts a draw on the vehicle and will kill your battery if left in place over time....
 

detthompson

New Member
Joined
Jan 3, 2022
Messages
1
Location
Daytona Beach. FL
Taking my 2007 Avalanche to the shop on Thursday. Same issue. Stab and Trac lights come on, engine sputtering and stalling at stop sign. Thought is was gas, but going to have my mechanic look everything over.
I am also in Central FL with the same problem. Possibly we are close enough I could use the same shop. Where did you take it?

thanks
 

CenFL Avalanche

Full Member
Joined
Aug 16, 2014
Messages
139
I am also in Central FL with the same problem. Possibly we are close enough I could use the same shop. Where did you take it?

thanks
I took mine to USA Transmission in Bradenton. Today, I drove it for the first time since Friday night. It stalled twice in the first five minutes. The second time, it had a hard time re-starting and gas cap light came on. Tomorrow I plug in my new Range AFM deactivator so it stays in V8 mode.
 

CenFL Avalanche

Full Member
Joined
Aug 16, 2014
Messages
139
Remember to follow the instructions about unplugging the device if you park your AV for several days since it puts a draw on the vehicle and will kill your battery if left in place over time....
Thanks; I saw that on the Range website and will unplug it when not daily driving.
 

gmAtech

Full Member
Joined
Jan 9, 2022
Messages
12
the 4 AFM lifters on that side are in cyl's 4 and 6, you have to remove the cylinder head to replace them that's why you needed a new gasket and whatnot. there are many updates to the engine for oil consumption google tsb 10-06-01-008M
 

CenFL Avalanche

Full Member
Joined
Aug 16, 2014
Messages
139
Range AFM deactivator helped during my daily in-town commute. No stalling and no noticeable MPG change. I am going to not drive it until Sunday and see how it does after sitting for a day and a half. I don't expect much of a battery drain anymore than my brake controller and dash cam lights cause.
 
Top