How to disable AFM/DOD at no cost

[Mooseman]

I was tired of the oil consumption and that weird feeling when it kicked in. Yeah, I know, you're not supposed to feel it but I did in mine. And my driving is half and half city and highway so mileage improvement with DOD is negligible. I know I can get it tuned out but I wanted to try it without DOD before committing. Did some research and found this info in GM-SI:

Fault Active or Fault Pending--displacement on demand (DoD) is disabled for the following faults:

- Manifold Absolute Pressure Sensor

- Brake Booster Vacuum Sensor

- Engine Oil Pressure Sensor

- Engine Coolant Temperature Sensor

- Vehicle Speed Sensor

- Crankshaft Position Sensor

- Engine Misfire Detected

- Displacement On Demand Solenoid Driver Circuit

So, I disconnected the Brake booster vacuum sensor. It was easy to access and would not affect anything else. Sure I got the check engine light but nothing else is affected and DOD is disabled.

It's only been a week so I haven't noticed any difference yet with oil consumption or mileage. I just have to scan it once in a while to check for any new codes. I will be getting a tune eventually but this will do just fine for now.

 

[Aarkon]

I may have to try this on the envoy I cant stand afm especially with my exhaust setup

 

[Mooseman]

I know I feel liberated

But, there isn't AFM on the 4.2 unless you're talking about another vehicle?

 

[Mounce]

He now has two 360's. His TB and now a 5.3 Envoy.

 

[The_Roadie]

Some people's brand loyalty knows no limits.

 

[07Denali]

im surprised you feel it kicking in and out. any exhaust mods? I get up to 24mpg pure highway and would hate to lose that.

 

[northcreek]

It's only been a week so I haven't noticed any difference yet with oil consumption or mileage.

From my understanding disabling DOD(AFM) does not stop oil consumption. Disabling it in the early life of the vehicle is supposed to halt or slow down oil ring fowling. This appears to be owner theory and not GM's. Though I wouldn't expect GM to blame AFM since they are more concerned with CAFE .

 

[Mooseman]

Yeah, who cares if you're spewing more oil into the environment as long as you're meeting some stupid guvment rule that gives an illusion they're doing something for the environment. So far, all those I have read that disabled DOD reduced their oil use. And my oil right now is as black as my truck and I'm only at 50% on the OLM, even with the 4 liters I have had to add in the last couple of months. Anyway, I'll see what happens.

I could feel it kick in, sorta felt like a very slight jerking motion and now it's gone so it isn't something else like the TCC.

 

[Aarkon]

I guess I dont really feel it kick in on my envoy but it annoys how it makes my exhaust sound like a damn Subaru and yes mooseman the envoy is an xl with the 5.3 only my tb has the i6

 

[smitty5150]

Just would like to add that I've done this to mine as a temporary fix. Usually, I has been seeing a nice puff about once a day. With the sensor unplugged, I've had no dod activation and no smoke at all. Just a smooth idle and an engine light.

 

[Mooseman]

My MPG's have been staying around 14 and oil consumption drastically reduced.

 

[Tiggerr]

Do all 5.3. GMT's have that DOD crap? Or just certain years? Was thinking about getting another rainier with v8

 

[Instrumental]

I believe 2007 was the first year for the DOD.

 

[Tiggerr]

Oic. Ok definitely don't want that garbage thought it was all of them. Maybe I'll just swap my LL8 out for an LS after all. Idk

 

[Sparky]

This is something I'm going to have to check on since my new-to-me Silverado has a 5.3 with AFM.

My only real concern with getting this truck is the AFM and oil consumption reports. Likely I'll just get it tuned out and be done with that part, but until then I don't know.

 

[djthumper]

I keep hearing that but mine is about the same since I bought it.

 

[C-ya]

I believe 2007 was the first year for the DOD.

I think it was 2005. My '05 had it stock. If your engine code is LH6, you have it.

 

[Tiggerr]

I think it was 2005. My '05 had it stock. If your engine code is LH6, you have it.

The rainier I have currently is a 2004 6cyl LL8. Was thinking of trying to find a low milage 2007 V8 2wd. Like a few of the changes they made later on with the interior, trim, and grill. Instead of changing the stuff on mine. They are proud of some of the trim for these things. Some I can't even find. Like the chrome piece on the tailgate. Mine's toast.

 

[smitty5150]

I believe 2005 was the inaugural year. Mine is 2006 and has it.

 

[dporter]

My 07 Denali has it and I never knew it was working until about 100k when it started using oil. 1qt /3000 miles. I can also feel it in the 4 cyl mode @ 30 mph on light throttle but its not bothersome to me. The oil use is only at high speeds and hills. If we just use the car around town I don,t have to add before I change at 5k or 6k. Car has 154,000 on it now.

Dave

 

[Aarkon]

I forgot to post this but it has been months since I did the delete and I used to have a rear main seal leak before I did it and now it has magically fixed itself havent lost a drop of oil in months

 

[Denali n DOO]

I'll have to try this. Is the sensor that needs to be unplugged in an obvious location?

 

[Aarkon]

Its just right on the brake booster

 

[dporter]

I would like to try this method but cannot figure out how to separate the connector at the booster. Also I am wondering which wire would be controlling the DOD. Might consider spicing in a simple open close switch.
Dave

 

[Mooseman]

Should be fairly simple. IIRC, it has a grey locking insert. Slide that out completely, press on the tab and pull. I think if you splice into the blue wire, it should work as it is the signal wire. Don't know if you will actually get Displacement on Demand on demand though. Might have to shut off the engine and re-start to get it working again.

 

[MountainMax]

Reviving this thread for my 9-7x.
@Mooseman - did you ever get the tune to permanently shut off the DoD or are you still running around sans-booster sensor/engine light?

If you did get the tune, which tune is it that will disable the DoD - the Lime-Swap or something different?

Thanks for the input!!!

 

[Mooseman]

Yes, I did get a tune. Doesn't matter who does the tune, you just have to request that DoD be disabled (or anything else for that matter, like the fan codes). I went with Lime-Swap because he's so much cheaper than PCMofNC, basically charging the same as for the I6, $99 IIRC.

 

[MountainMax]

Thanks @Mooseman

 

[Mike534x]

Hate to bump an old thread but I'm curious. Are the lifters still prone to collapsing with the DoD disabled? or does it just decrease the chances of it happening?

Lifter in Cylinder #4 collapsed on mine while out of town, its sitting inside a dealership with the head pulled. For whatever reason they're only replacing the driver side lifters instead of both sides. I was debating about having it tuned out if it helps prevent it from reoccurring.

 

[Mooseman]

Very timely your question as I am currently contemplating doing a cam and lifter replacement as my engine has developed a "sewing machine" type noise at moderate acceleration on the passenger side.

Doing a bunch of research, found this page. There have been instances of AFM lifters collapsing because of failed oil control solenoids or the lifter guides allowing the lifter to rotate. Other than that, design flaws were noted. Normally, oil pressure collapses the lifter in V4 mode and when it switches back to V8 mode, relieves that pressure in the lifter to allow it to come back to full height. When they fail, it's an internal mechanical failure preventing them to return. In that same page, it says that deactivation should prevent the AFM lifters from failing. But, this is assuming that the lifter guides are good.

From those that have reported failures, the repair was to replace ALL the lifters and in some cases, also replace the camshaft if it got banged on by the collapsed lifter. Why aren't they replacing all of them? Sure it will take more time and money but this would be the complete repair. If one failed, sure enough another will later on. They are idiots by not doing it properly. I would insist they do it right.

 

[C-ya]

@Mike534x , I'm guessing you are paying, or do you have an aftermarket warranty? If you are paying, find out the cost to do them all. If the warranty is paying, see if they'll do them all. I hate the mentality of "We'll only fix what is broken".

One other thing I noted was that you said #4 collapsed, but that they have the driver's side head off. Driver's side is odd numbered cylinders.

 

[Mike534x]

@Mike534x , I'm guessing you are paying, or do you have an aftermarket warranty? If you are paying, find out the cost to do them all. If the warranty is paying, see if they'll do them all. I hate the mentality of "We'll only fix what is broken".

One other thing I noted was that you said #4 collapsed, but that they have the driver's side head off. Driver's side is odd numbered cylinders.

D'oh. Sorry wrote this pretty late last night, it's the passenger side they pulled but I believe they pulled the drivers side as well because the Tech II was showing a pending misfire on #3. I questioned why they were only doing the one side and it's the same reason, "don't fix what isn't broke " which seemed strange because you might as well do them all as a precaution. I'm paying out of pocket for the repairs. I wish I had an aftermarket warranty though.

Very timely your question as I am currently contemplating doing a cam and lifter replacement as my engine has developed a "sewing machine" type noise at moderate acceleration on the passenger side.

Doing a bunch of research, found this page. There have been instances of AFM lifters collapsing because of failed oil control solenoids or the lifter guides allowing the lifter to rotate. Other than that, design flaws were noted. Normally, oil pressure collapses the lifter in V4 mode and when it switches back to V8 mode, relieves that pressure in the lifter to allow it to come back to full height. When they fail, it's an internal mechanical failure preventing them to return. In that same page, it says that deactivation should prevent the AFM lifters from failing. But, this is assuming that the lifter guides are good.

From those that have reported failures, the repair was to replace ALL the lifters and in some cases, also replace the camshaft if it got banged on by the collapsed lifter. Why aren't they replacing all of them? Sure it will take more time and money but this would be the complete repair. If one failed, sure enough another will later on. They are idiots by not doing it properly. I would insist they do it right.

It would be easier if they were local, sadly the break down happened 5 1/2 hours away from my home and it was cheaper to have the repairs done there then to locate a hauler to bring it back here. I questioned why they're only doing one side but they insisted that if it isn't broke don't fix it. I was told the cam survived with no damage since I got the engine off the moment the noise started.

 

[C-ya]

If you are paying out of pocket and can afford it, I would do both sides. I know how life is, though. I have less than 10K left on my aftermarket warranty.

 

[Mike534x]

If you are paying out of pocket and can afford it, I would do both sides. I know how life is, though. I have less than 10K left on my aftermarket warranty.

If I had enough I would get the other side done. Unfortunately, they're being stubborn and refuse to believe the other side will eventually go. They apparently have never seen a TB with the 5.3 let alone have one in their shop for a lifter collapse (so they say). I'll be glad once its back, already had to give it to them straight that I wanted it repaired after they tried to "talk" me out of fixing it given its age/mileage. Do you know what's considered "normal" as far as oil burning goes? I was about 1,500 miles into my oil change when I had to add nearly 1 1/2 QT's, haven't found any leaks so that has me puzzled and more curious about pulling one of the listed sensors Mooseman posted.

 

[Mooseman]

I would suggest you disable AFM before another one craps out on you. Best way is through a tune but disconnecting the sensor on the brake booster is quick, dirty and cheap until you do get a tune.

 

[C-ya]

I seem to remember someone saying GM told them that 1 qt per 2K miles was "acceptable". Not in my book!

I have had to add as many as 4 qts of oil at once to my truck before I really started keeping a good eye on it before my tune. I heard some nasty engine rattling going on at a stoplight and I thought, "I'm glad that isn't me!" The other car made a right on red and there I was, still listening to that nasty noise. A mile down the road, I was where I was going. Shut her down, checked the oil and it wasn't even on the stick! Limped a mile back to an auto parts store after the meeting and had to add almost 4 qts. That one scared me!

I remember adding 6 qts of oil (in total, not at once) in my first oil change interval. I think I got my tune shortly after that oil change. The last couple of oil change intervals had seen about 3 qts added over all. She's still thirsty, but not nearly as bad.

 

[Mike534x]

I would suggest you disable AFM before another one craps out on you. Best way is through a tune but disconnecting the sensor on the brake booster is quick, dirty and cheap until you do get a tune.

I plan on pulling it the moment I get it back, if there is one thing I liked about AFM was the 23 MPG I would get on the highway. At this point, I'd rather lose it for the time being to avoid a repeat. I'm assuming Lime-Swap would be the way to go to have it tuned out?

I seem to remember someone saying GM told them that 1 qt per 2K miles was "acceptable". Not in my book!

I have had to add as many as 4 qts of oil at once to my truck before I really started keeping a good eye on it before my tune. I heard some nasty engine rattling going on at a stoplight and I thought, "I'm glad that isn't me!" The other car made a right on red and there I was, still listening to that nasty noise. A mile down the road, I was where I was going. Shut her down, checked the oil and it wasn't even on the stick! Limped a mile back to an auto parts store after the meeting and had to add almost 4 qts. That one scared me!

I remember adding 6 qts of oil (in total, not at once) in my first oil change interval. I think I got my tune shortly after that oil change. The last couple of oil change intervals had seen about 3 qts added over all. She's still thirsty, but not nearly as bad.

Ouch! I wish it was 1 qt every 2k for me, but so far its been nearly 2 qt's every 1.5k-2k, though I think I've only ever put in maybe 3 or 4 during each interval. I did have a little bit of a noise the week before the breakdown, but it went away after filling it with another qt. That's an unsettling thought, pulling out the dipstick with nothing on it and hearing the noise to top it off.

I'm strongly considering the tune, but for now I guess pulling the sensor will have to make do. I know my wallet will slightly forgive me for not having to buy a qt of oil every few weeks.

 

[Mooseman]

@limequat (aka: lime-swap) is the way to go. He charges much less than the other guys, basically the same as the 4.2, unlike the other guys who almost triple the charge just because it's a 5.3.

 

[Mike534x]

@limequat (aka: lime-swap) is the way to go. He charges much less than the other guys, basically the same as the 4.2, unlike the other guys who almost triple the charge just because it's a 5.3.

Wow! that's insane.

I got the truck back today after taking an overnight train. Pulled the sensor near the brake booster and averaged around 16 MPG going 80 MPH. Really interested in seeing how it does once I start taking it into the city but I have to put it off since it's going back into the dealer (near my house) since the place that did the repair really made a mess of things.

 

[Mooseman]

Just be sure to reconnect the sensor or they'll plug it back in and charge you the labour for it!