I have a 2021 GMC Sierra, diesel, I really like my new ride! I avg 24 mpg and the multifunction tailgate is awesome! One thing though…I can’t stand the “aut start-stop” feature. I try to remember to turn off (dash switch) each time I crank up my GMC however I often forget. There has to be a way to disable that feature. Ya, I get it, supposedly turning off the engine while at a red light save fuel but the cost down the road of a new starter, I am sure, will offset any savings. Any ideas? thx mark in mansfield, tx
I wouldn’t worry about the starter cost, it was upgraded for the stop/start system. I’m not a fan of it, but I found it easier to live with if I started taking my foot off the brake and giving it a second to get the engine going before I hit the gas.
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A Chevy Cruze I rented in Texas a few years ago had that feature. It worked seamlessly and I liked knowing I was not causing unneeded energy consumption and air pollution while “idling.” I wonder if the starter motors are beefed up for this application.
Me, I wouldn’t mind a possible starter motor repair compared to the certainty of having my car do a socially responsible thing day in day out.
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The battery and starter are made just for this Auto/Start feature . If you did find a way to disable the feature you can say goodby to your warranty.
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This was discussed ad nauseum a year or more ago. Some think it is just great and others are annoyed. I’m in the annoyed group but can’t believe it’s good for a diesel especially. Sure might have beefed up parts but back about 85 I had to replace the beefed up starter in my diesel and the part was $300 when normal starters were around $80 new.
At any rate outside of messing with a sensor like the hood ajar switch, ya have to get into the software. Somewhere on a web site or YouTube someone showed the procedure but you have to be a 15 year old or software engineer to follow it. So gonna have to do some searching but I think ford was covered. No dealer will touch it and messing with the software may void a warranty. I assume the silly software is backed up by epa threats of huge fines.
There doesn’t have to be a way. If it can be turned off permanently, the manufacturer has to publish the fuel economy for when it’s turned off instead of for when it’s turned on, which of course they don’t want to do.
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If I had one of these, the first thing I would do is construct a small little timer circuit with a relay. Every time I started the truck, the timer circuit would activate the relay momentarily. The relay contacts would be across the dash switch. Now you have an automatic defeat for that feature with minimal intrusion on the system…
I think this would be a hot item. Plans? Timer circuit? No help from radio shack anymore.
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I just don’t see what the big deal is, regarding the disabling of auto start-stop.
When I began to drive my friend’s Forester with that feature, the first few times I drove it, I forgot to disable the auto stop-start. Now, it is like a reflex.
My starting routine for his car includes checking the mirrors, fastening my seatbelt, and disabling the auto-stop start.
If the OP has problems remembering to push that one button before he starts driving, he may well have other memory-related problems in his future.
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I’m not aware of any simple work-around to disable the auto-start function. If google doesn’t turn anything up, best bet imo is to grin and bear it. If it eventually wears out the starter, replace the part.
I had a BMW diesel rental about 12 years ago with this feature. At first it annoyed me, but after a couple days I got used to it. Maybe you can get used to it if you don’t let it bother you.
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There are so many options out there to choose from it is really not necessary to design your own. I just prefer doing it myself most of the time. Here’s one example:
I just want control over how my equipment operates. Another example is my newer lawn tractor that has numerous safety features that actually interfere with the normal use of the equipment. I cannot mow backwards without several interactions with the key position and button pushing operations. One would be enough. Also, the occupancy sensor is way too sensitive in cutting off the mowing operation. If I lean at all, it cuts out. This prevents cutting on even a slight incline. My son cannot mow because the weight required is too high (he is plenty old enough to mow and weighs 110lbs) and it keeps activating over any bump or shifting of seating position. So I disabled all of the OEM garbage and made my own. The occupancy sensor now has an accelerometer and infrared sensor. If the tractor tips or the operator departs the seat position, it cuts off. The nuisance activations are now eliminated and it works flawlessly without interfering and causing frustration. It cost about $15 in parts to make.
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My wife had a Ford Edge on loan from the dealer that had this feature. I found a way to disable it buried in the settings menu.
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Here’s the deal. Although the versions of these vehicles sold to consumers come with this feature, fleet and law enforcement versions do not come with this feature. Therefore, it should be possible to change the software in the PCM, or install a “tune” which disables the auto start/stop. I am sure it can be done, and that people have done it, although installing an unsanctioned “tune” could affect warranty coverage, even if the only change is to remove B.S. features like auto start/stop, or to tune out “reduced functionality” when the DEF runs out on a diesel vehicle.
Interesting. $10 and a little wiring and problem solved. I did a little modification of my mower too but more disconnecting. On to garage door openers.
How about using the parking brake instead of the service brake when stopping at a light?
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Parking brakes are rear wheels. You just generally slide with rear brakes only.
For the 1/2 ton Sierra there’s this which plugs into the existing wiring for the switch.
4D Tech | Chevrolet & GMC Upgrades, Replacements & Accessories
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A physical switch?
As a test hold down the switch before starting.
If it will disable with the switch held down then use a toothpick or hot glue etc. to hold the switch down.
I love me some cheap hacks. 
If the web is correct all this person has to do is press a button . Good Grief , how hard is it to do that .
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