2.3L 7MT — lurching/stuttering in low gears between 2-3k RPM

[thesocalexplorer]

Have experienced the "bronco buck" a handful of times. Always when the engine is lukewarm temp. Getting off the gas always fixes it. Haven't experienced mine in 3-4 months/3k miles now.

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[HoosierDaddy]

I'll throw my hat in the ring with this issue also. Has happened at least 3 times to me and/OR my daughter.
I'd agree it is a cold motor issue. Probably when it is switching from cold to hot calibrations/emissions etc etc.

The action reminds me of jumping on and off the throttle on a 1 ton truck with a granny gear. It will really rock you.
I'll never forget my first experience with that, all the mechanics at the shop LOL-ing, "YOU DON'T HAVE TO USE FIRST ON THOSE TRUCKS!!!"

 

[Mustbeheresomewhere]

Well, it finally happened to me. I’m just at about 1,000 miles. This morning after I drove it for a while and parked for an hour. I got back in it and started out and it started bucking in 1st gear. I guess they built the Bronco with bucking built in.

 

[SPITmadFIRE]

I haven't had it happen recently, but I doubt it's because of any breaking in/mileage. I'm just over 8,000mi now, and this issue happens essentially 100% of the time when the vehicle starts warm (not cold, not hot, but warm) with oil temps between 90-120F.

The best way to avoid it is either let the vehicle warm up for a few more minutes at idle, or granny shift from 1-2-3 at very low RPMs when you first get going.

 

[ColonelAngus]

I'd give it some time, see if it gets better once you put some miles on it. Did you refill with a higher or lower octane by chance? Also I know this probably a stretch but any chance you are losing a little traction and the ESP is kicking in backing your throttle down? Can cause a similar sensation at lower speeds.

 

[SPITmadFIRE]

I'd give it some time, see if it gets better once you put some miles on it. Did you refill with a higher or lower octane by chance? Also I know this probably a stretch but any chance you are losing a little traction and the ESP is kicking in backing your throttle down? Can cause a similar sensation at lower speeds.

It's definitely not any sort of traction control kicking in -- if anything, this sort of throttle response would cause loss of traction on slippery surfaces because of how violent it is.

If you haven't experienced the issue first hand, it's extremely noticeable. The throttle body is essentially slamming shut, then immediately opening wide, before repeating the cycle causing the truck to jerk around and oscillate until you take your foot off the pedal or shift.

 

[ColonelAngus]

It's definitely not any sort of traction control kicking in -- if anything, this sort of throttle response would cause loss of traction on slippery surfaces because of how violent it is.

If you haven't experienced the issue first hand, it's extremely noticeable. The throttle body is essentially slamming shut, then immediately opening wide, before repeating the cycle causing the truck to jerk around and oscillate until you take your foot off the pedal or shift.

Well... that sounds extremely unpleasant...

 

[NJRoadkill]

I haven’t had it happen past the 3k mile mark. I’m at 11k now.

it usually happen right after a cold start. Getting off the throttle for a second to “reset“ it always did the trick. It didn’t happen often even them; maybe 5-6 times.

 

[Ford Motor Company]

Well, it finally happened to me. I’m just at about 1,000 miles. This morning after I drove it for a while and parked for an hour. I got back in it and started out and it started bucking in 1st gear. I guess they built the Bronco with bucking built in.

Hey there! I can look into your Bronco’s lurching concerns on my end if you’d like. Will you send us a private message with your VIN and dealership info?

 

[ColonelAngus]

Hey there! I can look into your Bronco’s lurching concerns on my end if you’d like. Will you send us a private message with your VIN and dealership info?

While you're at it could you look into getting my Bronco built... its been over 2 years now... k thanks!

But thank you for the forum presence and keeping an eye on customer concerns and issues... just hope engineering and corporate are paying attention...

Never thought I'd say it, but right now I'd be happy to have a bucking bronco to worry about vs a deck of cards, hammock, etc, and no idea what's happening or what to expect.

I'll end my thread hijacking now.

 

[Mustbeheresomewhere]

While you're at it could you look into getting my Bronco built... its been over 2 years now... k thanks!

But thank you for the forum presence and keeping an eye on customer concerns and issues... just hope engineering and corporate are paying attention...

Never thought I'd say it, but right now I'd be happy to have a bucking bronco to worry about vs a deck of cards, hammock, etc, and no idea what's happening or what to expect.

I'll end my thread hijacking now.

Hope it gets built soon, you’re going to love the manual transmission!

 

[Karl_in_Chicago]

Hmmm, 30 years ago I'd have said to check the position of *this* knob . . .

 

[bradcd]

I've been following this thread for a while since before I had my Bronco. I wanted to chime in with some of my experiences 2,000 miles in. I think that I have some of the lurching described on a cold engine but I think that it only occurs for me if I'm shifting above 3K rpm. If I shift early and am very smooth with the clutch release (which I should be doing anyway in the lower gears on a cold engine) the lurching isn't present. The ECU definitely has the ability to feed a little throttle to keep the engine from stalling. I can feel that when slowly releasing the clutch in first gear without applying anything from the accelerator pedal. I have noticed some bucking sometimes while shifting from 5th to 6th even. It behaves like rev hang, where my shift up around 2.5K doesn't fall and the entry into 6th lurches forward a little to meet the like 2.2K it should be at. Normally I can shift up to 4th, 5th, and 6th as fast as I can get off the clutch without issue.

With all that said, I think that there is a software/tune involvement that hasn't been discussed. Ford recently released their performance tune package that adds auto rev matching to down shifts. So there must be beyond just a mechanical component in the system to read and interact with the engagement/throttle relationship. That feature can be enabled via software so the manual trans is more than just simple mechanical. I don't think it's a stretch to think that the software could incorrectly read parameters from time to time and interject some more variance. I have a Sprint Booster (level 5 of 18) installed on the pedal as well so that could also be exaggerating parameters back to the software on what it thinks that it needs to account for.

 

[JD11937]

I've been following this thread for a while since before I had my Bronco. I wanted to chime in with some of my experiences 2,000 miles in. I think that I have some of the lurching described on a cold engine but I think that it only occurs for me if I'm shifting above 3K rpm. If I shift early and am very smooth with the clutch release (which I should be doing anyway in the lower gears on a cold engine) the lurching isn't present. The ECU definitely has the ability to feed a little throttle to keep the engine from stalling. I can feel that when slowly releasing the clutch in first gear without applying anything from the accelerator pedal. I have noticed some bucking sometimes while shifting from 5th to 6th even. It behaves like rev hang, where my shift up around 2.5K doesn't fall and the entry into 6th lurches forward a little to meet the like 2.2K it should be at. Normally I can shift up to 4th, 5th, and 6th as fast as I can get off the clutch without issue.

With all that said, I think that there is a software/tune involvement that hasn't been discussed. Ford recently released their performance tune package that adds auto rev matching to down shifts. So there must be beyond just a mechanical component in the system to read and interact with the engagement/throttle relationship. That feature can be enabled via software so the manual trans is more than just simple mechanical. I don't think it's a stretch to think that the software could incorrectly read parameters from time to time and interject some more variance. I have a Sprint Booster (level 5 of 18) installed on the pedal as well so that could also be exaggerating parameters back to the software on what it thinks that it needs to account for.

I’ve been thinking this may be a software issue also. Even though this seems to happen randomly I have most successfully been able to recreate it under higher load situations. I’m bringing my bronco into the dealer to have them take a look this Saturday, let’s see what they say.

 

[Lakelife36]

Ford recently released their performance tune package that adds auto rev matching to down shifts.

I'm really missing that yuck emoji these days. A*to throttle tip-in, hill hold, and now this.

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