How to disable AFM/DOD at no cost

[lenlo]

MooseMan - I tried the brake booster sensor disconnect on my 2008 Suburban with LC9 to troubleshoot the cloud of smoke I'm getting at cold startup 20% of the time and narrow it down to DOD/AFM. At first the DIC just said 'Service Brakes Soon'. I then got a CELight - I'm assuming it's due to the brake booster sensor being disconnected and not a P1174 'Fuel Trim Cyclinder Balance Bank 1' that I got about a week ago that I also think is related to the DOD/AFM... I digress. Even with the Ck Eng Light, According to the DIC, it is still going into V4 mode.

Can the 5.3l in the Saab and the Burban be that different?

BTW - I have an '08 9-7x Aero too so I'm also a GMT fan. Really like the post you did on the running light change to fog lights. It was an easy change and I'm sure saved the lens from burning up.

 

[Mooseman]

Could be different for the full size trucks. I just know it worked on my 06 9-7x. I used the AFM troubleshooting guide in GM-SI.

Does your 08 Aero have that sensor? If so, then the PCM uses it for something else since the 6.0L doesn't have AFM.

 

[lenlo]

The '08 Burban - I have no access to GM-SI, just what I find from google. I see some folks with Pontiac Gx's have suggested the same that you originally recommended to unplug the brake booster vacuum switch to disable AFM temporarily so I know it's more than just GMT360's that your solution works on.

I know about the Aero - Haven't looked. That one runs good, even though on cold start up it does have a faint lifter tick or piston slap at 133k. I can't tell which? It's one petrol thirsty beast of a motor. I should add, not terribly different though from both I6s I owned, one in another SAAB and another in an Olds.

 

[northcreek]

I put one of these on my 07 over a year ago and it's been working like a charm.They are a little pricey but, have come down a bit from what I paid. The nice thing is that you can move it to your next AFM vehicle, it works on all GM AFM vehicles...Mike.
http://www.ebay.com/itm/RANGE-TECHN...ash=item4af3746ee4:g:t7EAAOSwwbdWOsKj&vxp=mtr

 

[Mooseman]

I'd go for a tune at that price. AFM delete and the benefits of a tune

and

The title of this thread says "at no cost". That obviously isn't

 

[northcreek]

Yeah, I hear ya but, I'm a little troubled with messin' with my ECM and the inconvenience of getting it done...I like plug n play...

 

[enrique]

Hello, a question to the moderator of the group. If I disconnect the vacuum sensor from the brake booster to deactivate the AFM there would be some danger when the truck is suddenly braked, that is, it could bring some consequence or not. Thanks in advance

 

[Mooseman]

None at all. That vacuum sensor is used only for the AFM. You just disconnect the electrical connector and leave the sensor in place.

 

[enrique]

Thank you. One last question the connector that I am going to disconnect is located in the brake booster at the bottom take a picture and the part number is 0 261 230 130 is bosch brand made in germany is the pressure sensor. My question is the one that I have to disconnect. Thanks greetings from Venezuela

 

[Mooseman]

I don't know all that and I'm not at my truck right now but there is only one on the brake booster. Can't go wrong.

 

[enrique]

I have the doubt because the brake booster of my 2008 tahoe brings two connectors one on the top and one on the bottom. The one on top is next to a hose and it is small and the other one is down next to a decal that says AFM and is bigger. Which of them I disconnect to deactivate the AFM. Sorry for the inconvenience and thank you again,

 

[enrique]

Brake Booster with pressure sensor
Part# 159 47019, 0 261 230 130
Fits:
Escalade 2007-2008
Yukon Sierra Silverado Tahoe Suburban 2007-2008
Avalanche 2008

 

[Mooseman]

Ah well, that explains a bit better. Sorry, I wouldn't know since this is my experience with GMT360, not the full size. If I were to guess, I would say the one with the decal that says AFM. Either way, I don't think you'll break anything. Try it and see what happens.

 

[enrique]

Thank you very much friend if I try with the connector below that for me is the vacuum sensor of my 2008 tahoe and I will try to disable the 4v mode that spends a lot of oil. I will inform you at least I know that the brakes will not go away. Merry Christmas

 

[CajunWon]

Will any shop know how to tune out DOD?

Here's a vid on how to free the stuck lifter

Have read that DOD does not provide any fuel economy.

 

[Mooseman]

Will any shop know how to tune out DOD?

Mostly performance shops but others might know somebody local that can. Ask around.

Have read that DOD does not provide any fuel economy.

Yup. That would be me. I did tests on both the Saab when it still had it and my Caprice and I saw little to no fuel savings. It's an absolutely useless and troublesome system.

As for that video, I've seen it before and yes, that can be done however the failed lifter will still be there and will work only if the cam wasn't damaged by being banged by the stuck lifter.

 

[CajunWon]

Although having no issues: disconnected brake booster sensor.
Might be a little better throttle response.
However, pulling from a complete stop is different. Would always jerk away from stop, even when careful on the pedal, no more! I had attributed this to the 3.73 gearing, guess it is in 4 mode when stopped and kicks into v8 a bit too quickly.

 

[Mooseman]

No, it doesn't go into 4 cyl. mode at idle or when stopped. The times when it can be in 4 cyl. mode is very narrow; at steady cruising speed, no acceleration at all, no increase in power demand (i.e. uphill), no applying brakes (vacuum sensor), Between certain speeds, adequate oil pressure, and it has to reactivate all cylinders every 10 minutes to re-pressurize the shut down cylinders.

 

[CajunWon]

So, how can I verify that I have DOD and it is working?
The dealer window sticker says it has DOD, but there are no indicators to tell me when in v4 mode.

 

[C-ya]

So, how can I verify that I have DOD and it is working?
The dealer window sticker says it has DOD, but there are no indicators to tell me when in v4 mode.

These vehicles seem to activate and deactivate very smoothly. For me, I could tell when I was cruising through a corridor of buildings in my small downtown about 30 mph with the windows down. There was a slight odd tone to the exhaust. I could put it in N and it would change (go back to V8). Put it back in D and shortly after, while still maintaining speed, the tone would change again. With my tune, I do not get that change in tone.

 

[Mooseman]

If you have DOD, it will have that vacuum sensor on the brake booster. There isn't any indication in the DIC or anywhere when you're in 4 or 8 cyl. mode in these trucks. I could feel it changing in the Saab but not in the Caprice (which does have an indicator). If it's working correctly, you won't get a CEL or code unless it's already been tuned out. High oil consumption is also an indication it's working (and drops when you turn it off)

 

[CajunWon]

Preparing to send PCM to PCMofNC for their $60 Turn Off DOD service. Surprised they didn't reply with more benefits of a performance tune -They did mention 10-15 horsepower gain, but at the expense of 91 octane fuel.

Not having issues, but oil does get dark quickly, and ~2qts between changes. Mainly, those stuck lifter failures has me, overly?, concerned.

PCM looks easy to remove, just push a tab to release a lever and remove, no bolts/nuts. Assume to disco battery whole time PCM is out. Might require Security re-learn.

 

[C-ya]

So, how can I verify that I have DOD and it is working?
The dealer window sticker says it has DOD, but there are no indicators to tell me when in v4 mode.

Forgot to address this so I quoted you again so you would get the notice. If you have LH6 in your RPO code list (glovebox), or you have VIN code M for your engine, you have a DOD/AFM engine.

From Wikipedia:

LH6
The Vortec 5300 LH6 (VIN code "M") with Active Fuel Management replaced the LM4 for 2005, and was the first of the Generation IV small block V8 truck engines to go into production. The LH6 produced 300 to 315 hp (224 to 235 kW) and 330 to 338 lb·ft (447 to 458 N·m). It is the aluminum block counterpart to the LY5.

 

[C-ya]

Preparing to send PCM to PCMofNC for their $60 Turn Off DOD service. Surprised they didn't reply with more benefits of a performance tune -They did mention 10-15 horsepower gain, but at the expense of 91 octane fuel.

For $39 more, Jeremy (@limequat ) will do what you want with the ECM and TCM. The TCM would need to be sent to him to do any changes you want in the transmission. I had him firm the shifts up slightly. He can also tune the ECM for various other goodies. He updated my fuel tables so I can run whatever fuel I want, gave me a 300 mph speed limit (that's nice on the highway!) and of course, turned off DOD.

 

[Mooseman]

I have to agree with @C-ya . A performance tune, even just a mail order one, really wakes this beast up. Can also take out PWM engagement of the torque converter clutch as well as torque management for quicker throttle response. Just remember you have to send both the PCM and TCM (Transmission Control Module).

 

[C-ya]

I knew there were other things. He shortened the delay between the pedal and the throttle body by modifying the torque management setting, and disabled the PWM for the torque converter. @CajunWon , if you send it to Jeremy, just ask him to put my tune in.

@Mooseman , is it still a PCM for the V8s since there is a separate module for both? Never know quite what to call them.

 

[CajunWon]

I knew there were other things. He shortened the delay between the pedal and the throttle body by modifying the torque management setting, and disabled the PWM for the torque converter. @CajunWon , if you send it to Jeremy, just ask him to put my tune in.

@Mooseman , is it still a PCM for the V8s since there is a separate module for both? Never know quite what to call them.

If I understand: the PWM manages TCC slippage so as not to notice as much when torque converter engages, turn off PWM and firming up shifts means you feel the shifts more but in theory increases life of transmission and TCC.?
How much does mpg suffer when Jeremy adjusts ignition timing and power modes?

 

[C-ya]

If I understand: the PWM manages TCC slippage so as not to notice as much when torque converter engages, that and firming up shifts means you feel the shifts more but in theory increases life of transmission and TCC.?
How much does mpg suffer when Jeremy adjusts ignition timing and power modes?

Correct. The PWM signal allows slippage which causes wear. The modification allows it to act more like a "locked converter". I don't notice it locking and unlocking like my previous GMC p/u did, but it doesn't seem to "float" like it did before.

My mpg remained very close to unchanged with the tune but I didn't/don't drive it on the highway for long distances much. It made almost no difference for my normal around town stuff. Best highway mileage I have gotten before the tune was about 19-20, and the best after is about 18-19 on the two major trips I have taken in it. My normal around town stuff is about 13 in the summer and 10-11 in the winter due to idle warm-up times.

 

[Mooseman]

Correct. The PWM signal allows slippage which causes wear.

Along with heat and breakdown of the fluid.

PCM, ECM, ECU, in my view, are interchangeable. Just the tranny controls are out of it now. we know what we're talking about.

As far as MPG, I mentioned in another thread that DOD, at the time, was advertised to save a paltry 5%. @C-ya 's numbers are on par to what I got with my Saab.

 

[CajunWon]

Shipped to limeswap thanks for the referral! It is a Vortec 5300 LH6 (VIN code "M")

 

[CajunWon]

Lime swap exceeded expectation of turnaround time. Plug'n'Play shifts are firm but not harsh. Speed limiter was only raised to 255 but I'll need new tires to test. Like that it hangs on to 4th w/TCC lock below 45 on flat road

 

[C-ya]

I got his "general" firm shift tune at first but over time, I wanted the 1-2 a bit softer. I was back over on his side of the state for a Tough Mudder so I stopped by for a quick update at no charge on a Sunday morning. He was gracious and got the update done quickly and I was off.

 

[Helikido]

Anyone any current tuners for the 9-7x that can tune out AFM?

 

[Mooseman]

Home

Lime-Swap swap reflashes and parts

www.lime-swap.com

 

[rmintz68]

I have an 07 avalanche with a LC9. I unplugged the brake booster sensor but the information center still shows it going from V8 to V4?

 

[Mooseman]

Look for another sensor on the brake booster. Another method would be to just unplug the VLOM.

 

[rmintz68]

Look for another sensor on the brake booster. Another method would be to just unplug the VLOM.

I will look for another sensor tomorrow. Thanks. Your saying you can just unplug the VLOM connector? I had a lifter collapse last year on the passenger side. Replaced both cylinders lifters and was going to just leave the VLOM unplugged during the reinstall but found online people saying you still had to disable the AFM through the computer.

 

[Mooseman]

For sure the tune would be the best permanent method. Did a little more research and you're right. Unplugging the VLOM would activate the solenoids so they work in reverse (power off to activate DOD)

Unplugging AFM solenoids???

Hey all, so I had a party in my garage last night, and during the guy talk of everyone's truck, we got on the subject of the oh so wonderful AFM. My friend is a service manager at a dealership and he had "all data" on his iPhone. He looked it up on his phone and said the AFM is actuated by 4...

www.silveradosierra.com

 

[Turbobob]

Tried this on my 2007 GMC Yukon 1500 and it did not work

 

[Mooseman]

On full size trucks, I believe that there is a second vacuum sensor on the booster. Try that one. On GMT360/370, it absolutely works.