Conventional Wisdom — Bronco Engines Are Detuned for Break-in — True or False?

[mpeugeot]

You have to remember that the base tune of the 2.7 will be conservative and as the computer monitors the engine, it likely starts advancing the timing, trimming fuel, and playing with the camshaft timing within the parameters that Ford engineers allow. What this means is that the motor, following a ECU reset will require time to adjust all the parameters to get the motor to work at its peak efficiency and power. I would fully expect this to be the case with any modern engine ECU. For instance, the motor makes 400 ft/lbs on 87 octane, but feed it higher octane (91/93) and the ECU will adjust fuel trims, timing, and cams to take advantage of the additional octane. Put bad quality gas in it and the knock sensors will put an end to that quickly, lowering the power significantly. Reset the ECU and it will start from the most conservative tuning parameters and advance forward until the engine sensors provide data or engineering limits are reached to reign in the party. That's why early on, it may not be running at its highest possible output.

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[johndeerefarmer]

Conventional wisdom circulating throughout the forum is that the Bronco engines are detuned during the break-in period (i.e., during the first 1,000 miles). Ever since test drives commenced weeks ago, I have read this claim dozens of times by different members, each of whom unquestioningly believe it to be true. Members who make this claim assume that the control units in the Bronco’s drive train are coded like those in a new sports car or a finely tuned exotic, which must be protected from user error until properly broken in. It’s a nice theory, but I’m not really sure it’s true, so I’d like to address it here.

If anyone can provide proof that this claim is true, we can all move forward knowing the conventional wisdom is gospel. On the other hand, if anyone can shoot down this claim with evidence, then we can put this conventional wisdom to bed once and for all, and any future incantations can be refuted simply by referring back to this thread.

Honestly, I really don’t know whether it’s true or not, but I’d like to find out.

So let the debate begin!

False. Engines are broke in at the engine factory. Tranny doesn't need break in but does need time to learn your driving style.
Super Duty's have the power limited in first gear to save breaking drive shafts but it stays that way- you don't get more power later

 

[johndeerefarmer]

"gear shopping"...

I like that phrase. Whenever I drive my Dad's eco-boost it's always hunting for the right gear, and really lags on the downshift unless I use Sport Mode or simply lock out the higher gears. His new one is the 3.5, but his 2.7 did the same. Drove me nuts. Thought it was turbo-lag at first, but it was just really lazy downshifting.

When we first got my wife's F-150 in April, it would shift into 10th gear at 45 miles per hour. Dumb. Now it behaves better and usually will dwell in 8 or 9. So the adaptive transmission does learn something over time.

If you don't like Ford's shifting strategy then have 5Star tune your ecoboosts. They have tuned several for me and the shifting is good.

 

[Wanted33]

The 2.3L in my Ranger was not detuned. Ford left it up to me to follow the break-in procedure. It was the same when I bought my 2013 F-150 w/5.0L, the wife's '13 & '18 Mustang 5.0's. So, I don't see them changing anything with Bronco. I think this assumption may come from some that have not driven a vehicle in the same class as the Bronco. Like the Jeep it is a heavy brick, and it's not going to be the quickest from a dead stop, or a WOT when passing. You just have to get used to it, and know how to apply the power before you make a move. Just the nature of the beast.

 

[FourHorses]

Owned three ecoboost engines here. Two of them with the 10 speed, one with a six speed auto. I have never noticed or felt a difference after 1000 Miles. The self learning transmission I have noticed and felt.

 

[mpeugeot]

False. Engines are broke in at the engine factory. Tranny doesn't need break in but does need time to learn your driving style.
Super Duty's have the power limited in first gear to save breaking drive shafts but it stays that way- you don't get more power later

Absolutely, there are a number of reasons for the "break in" period, most notably is liability. If something is wrong in the first 1000 miles and you are pounding the tar out of the vehicle, the consequences are much more likely to be serious under extreme conditions. The motor is broken in prior to installation and in reality is broken in for the most part within 20 mins of operation (all the wear surfaces). Although, I wouldn't be surprised if Ford broke the engines in for about an hour, just to make sure that they were solid.

The computer does have a period of time that it requires to learn that things have improved with regard to fuel quality, but honestly, it doesn't take all that long, unless the engineers have limited the speed in which change occurs. There is an wide variety of things that can be done with the software and honestly we don't know how Ford elected to calibrate the motor in the Bronco. However, a dyno would help determine the truth.

 

[Deleted member 3063]

"gear shopping"...
I like that phrase. Whenever I drive my Dad's eco-boost it's always hunting for the right gear, and really lags on the downshift unless I use Sport Mode or simply lock out the higher gears. His new one is the 3.5, but his 2.7 did the same. Drove me nuts. Thought it was turbo-lag at first, but it was just really lazy downshifting.

Could it be that it learned your Dad's style and he thinks it's acting strange after you drive it?

 

[TRMFAM]

Not sure if the PCM is de tuned but it is set to “learn”. Ford sells vehicles that go to sea level up to +8000ft. Drivers drive differently and could move from Miami to Denver. The PCM takes all the sensor inputs and modifies the program for optimal performance.

I think he has it right...at the Raptor Assault this was asked about the Raptors and the instructors said no but the computer is learning every time you drive and how you drive in each mode and storing those tables to set the acceleration / shift points / steering / braking / etc. to match your style and the truck could "feel" faster to you after you have driven it a while and it learns how you drive.

 

[BroncoBuckaroo]

Actually, neither of those documents say that explicitly. That’s just how you interpreted the text, which is a good example of how conventional wisdom develops and propagates.

For the record, this is exactly what those two source documents that you referenced say about the subject…

Bronco Nation article:

Owner’s Manual:

well did you prove that ”may exhibit some unusual driving characteristics“ doesn’t mean computer manipulation of the engine systems?

hmmm...well they definitely do it for snow mobiles according to this, so why not automobile engines.

http://www.arcticinsider.com/Article/Explained-C-TEC2-Automatic-Engine-Break-In

 

[VoltageDrop]

Why is it tuned so soft off the line? No clue. My guess? Drivetrain longevity. It can probably be tuned out in the ECM. The motor feels great in pretty much every scenario except “off the line performance. It wouldn’t likely come up with testers until the 0-60 instrumented tests. As many have also mentioned, the Bronco, particularly in Badlands trim, is very heavy. In the drag race I mentioned, with 3 passengers in my Bronco vs 1 in the Ranger, we estimated roughly 900 lbs of weight difference. Ford has a long, long history of making vehicles heavier than initially anticipated

I think you're right and I'm not sure if I should be concerned or just annoyed that they're doing this. I wonder if the transfer case clutch is the concern or if it's the 10R60. To have a 4.71 first gear and 4.7 final drive ratio and still be slow off the line is poopy.

 

[rtaylor]

most 3.5L TT engines live their entire life de-tuned to protect the drive line.
aftermarket "tuners" laud the horsepower they create while all they're doing is defeating the built in de-tuning.

True, but probably the bigger issue is avoiding complaints and false warranty issues. For example, stock tune has lots of margin to work with wide range of octane and poor quality fuel. Pedal response is crippled to prevent wheel spin, fast acceleration, loss of control, aggressive downshift, tire chunking, and erratic response for drivers with limited skills. Ford knows that most of their customers are soccer moms and not race car drivers, so the launch is very soft.

Installing a tune for fixed octane that sharpens the pedal response makes a big difference in ecoboost trucks. With 2.7L, 4.7's, and 4A there is no reason you can't have a strong launch if you want.

I know Ford has detuned gt500's (primarily for transport/delivery purposes), but I don't know why they would do that for trucks.

 

[Razorbak86]

well did you prove that ”may exhibit some unusual driving characteristics“ doesn’t mean computer manipulation of the engine systems?

hmmm...well they definitely do it for snow mobiles according to this, so why not automobile engines.

http://www.arcticinsider.com/Article/Explained-C-TEC2-Automatic-Engine-Break-In

I never intended to prove your interpretation wrong. I just proved that what you claimed those documents said was not true, and then I posted the specific text that you interpreted.

Now I’m going to do the same thing again for your snowmobile example. Your claim about snowmobiles is another classic example of conventional wisdom, because your own source document refutes your claim in the 2nd to last paragraph.

To be clear, the engine isn’t being controlled via the ECU any differently from 6 to 12 hours, rather it simply takes upwards of this many hours for the engine components to fully wear-in…

 

[ZackDanger]

well did you prove that ”may exhibit some unusual driving characteristics“ doesn’t mean computer manipulation of the engine systems?

hmmm...well they definitely do it for snow mobiles according to this, so why not automobile engines.

http://www.arcticinsider.com/Article/Explained-C-TEC2-Automatic-Engine-Break-In

If you’re teaching a kid to ride a bike, and they keep falling over and running into things at first, it’s not because the kid is deliberately riding like a jerk until he thinks you’re ready to handle a mini Lance Armstrong…

….it’s because he’s learning the parameters he’s working within and adapting appropriately.

There is no evidence presented yet to support the notion that the ECU is deliberately de-tuning itself during the first 1,000 miles.

 

[Krimzun]

I think its complete BS, the only factor here is adaptive learning with the transmission. On a side note having ordered my fair share of cars over the years. I've never had a break in period where I was told I couldn't get on the car right away. Hell the challenger I test drove before ordering mine had maybe 50 miles on it and the sales person was like let er rip there was no babying period needed. Another urban legend, most engines are tested at the factory its complete bs and just marketing/legal stuff.

 

[pandapaul]

I put it in C and just idled up a big hill on a fire road the other day. Top down, tunes on, just going 1 mph through the woods I’m really enjoying the 7-speed.

This sounds so wonderful. Imagining it brings a smile to my face.

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