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

[Sparkherd]

This has happened twice now, on my 2.3L 7MT badlands 4dr — in first and second gear. I’ll be in gear, slowly climbing through the revs right before I shift around 3.5k or so, and the car will kind of lurch back and forth almost like I’m applying throttle and letting off, over and over. Feels like a yo-yo effect a bit. My foot wasn’t on the clutch pedal whatsoever, but as soon as I press in the clutch to shift, it stops. Has only happened when the car is relatively cold and it’s the first time I’m get up to road speed after starting it.

My 2010 Ranger 4L does that when it's not warmed up; not too bad, feels like a miss.
It's done that since it was new and it's got 69K on it now.

Sponsored

 

[yabu00]

This has happened twice now, on my 2.3L 7MT badlands 4dr — in first and second gear. I’ll be in gear, slowly climbing through the revs right before I shift around 3.5k or so, and the car will kind of lurch back and forth almost like I’m applying throttle and letting off, over and over. Feels like a yo-yo effect a bit. My foot wasn’t on the clutch pedal whatsoever, but as soon as I press in the clutch to shift, it stops. Has only happened when the car is relatively cold and it’s the first time I’m get up to road speed after starting it.

I only have about 350mi on it so far, so wasn’t sure if this is simply a break-in quirk or not. It does feel like some amount of ECU learning could smooth it out, or possibly a turbo/wastegate/vacuum leak issue? I remember seeing someone else’s thread talking about their clutch acting strange similar to this but couldn’t find it by searching.

I’ve experienced the same thing. Talked to some people about it and they guessed it was a quirk of having a direct injection engine when in lower torquey gears.

Someone also suggested it may be an issue with the parking break disengagement.

 

[Mattyfly42]

experience the same thing. Occasionally. Used to experience it in my 90 wrangler. Usually just push in the clutch and shift to second. only happens when cold or moderately warmed up. More concerned with my transmission noise right now. ugh!

 

[tourproto]

I had this happen a couple of times early on - but, it stopped. I’m at almost 7k and hasn’t happened since 1000-1500 or so. If it kept happening, I would have been concerned. Just chalked it up to break-in.

This happened a few times with me early on, and I think it has happened once or twice recently but I attributed it to colder weather and shifting at too low of an RPM, kinda like lugging the engine.

 

[bradcd]

This happened a few times with me early on, and I think it has happened once or twice recently but I attributed it to colder weather and shifting at too low of an RPM, kinda like lugging the engine.

If you think you're shifting too low in the rpm, like at 700 rpm from 1st to 2nd, then you're experiencing something different than the bucking described here. The ECU is giving your super early shift an acceleration/blip bump because it's trying to keep the engine from dying. It's a very slight jolt that brings you up in speed compared to the heavy buck.

I do get the bucking somewhat often, maybe every 10 times out of my driveway. It is always on a cold engine and outside temp doesn't seem to have any affect on it. But I've also experienced weird rev hang in 5th gear at 2.6K rpm/68mph going into 6th which sometimes goes immediately in at 2.1K rpm, sometimes it sticks at 2.6K for upwards of 2 seconds before falling. That feeling then is much like the shifting at very low rpm with blip bump. I get this rev hang at a very very consistent location near my home, going up a long slight incline.

I'm wondering how connected my 1st gear cold bucking is to the rev hang because ultimately they're both during or immediately related to driving on an incline. My driveway is quite steep so I am driving up my drive in 1st gear at 3K rpm because I have to to keep from killing the engine. My routine to drive the Bronco is to reverse out of my flat level garage into my down sloped driveway. Clutch to first and the Hill Assist lets me get going up my driveway incline easily to get back out to a flat street. Right when I hit my flat street is when I experience the bucking and once I get up to a decent speed and hit 3rd gear it's all gone.

Who else that experiences the low gear bucking is driving on a slope or has the Hill Assist engage very early in your drive? I think this all might be software related to how the vehicle's Pitch is being measured. Hill Assist only kicks in as needed if the Pitch is outside of a certain threshold. I have tested with Hill Assist turned OFF and still continue to get rev hang sometimes in my 5th to 6th gear example. I haven't tested enough times to see if the low gear bucking completely goes away with Hill Assist off out of my steep driveway but will leave it off for a week and see if there's a difference.

 

[SPITmadFIRE]

If you think you're shifting too low in the rpm, like at 700 rpm from 1st to 2nd, then you're experiencing something different than the bucking described here...

I would like to see anyone get their RPMs as low as 700 without stalling, even when not in gear. If your RPMs ever dip below 800 in a forced induction, DI, 4cyl engine you will feel why they named the truck Bronco as it bucks and comes to a complete standstill.

 

[bradcd]

I would like to see anyone get their RPMs as low as 700 without stalling, even when not in gear. If your RPMs ever dip below 800 in a forced induction, DI, 4cyl engine you will feel why they named the truck Bronco as it bucks and comes to a complete standstill.

Haha I just went for a quick drive before claiming that 700. Ok, fine, 750rpm going very slightly down a hill.

 

[SPITmadFIRE]

Haha I just went for a quick drive before claiming that 700. Ok, fine, 750rpm going very slightly down a hill.

Ford doesn't want you to know this huge WARRANTY HACK -- piston rings HATE him!!!

 

[dejones64]

If you think you're shifting too low in the rpm, like at 700 rpm from 1st to 2nd, then you're experiencing something different than the bucking described here. The ECU is giving your super early shift an acceleration/blip bump because it's trying to keep the engine from dying. It's a very slight jolt that brings you up in speed compared to the heavy buck.

I do get the bucking somewhat often, maybe every 10 times out of my driveway. It is always on a cold engine and outside temp doesn't seem to have any affect on it. But I've also experienced weird rev hang in 5th gear at 2.6K rpm/68mph going into 6th which sometimes goes immediately in at 2.1K rpm, sometimes it sticks at 2.6K for upwards of 2 seconds before falling. That feeling then is much like the shifting at very low rpm with blip bump. I get this rev hang at a very very consistent location near my home, going up a long slight incline.

I'm wondering how connected my 1st gear cold bucking is to the rev hang because ultimately they're both during or immediately related to driving on an incline. My driveway is quite steep so I am driving up my drive in 1st gear at 4K rpm because I have to to keep from killing the engine. My routine to drive the Bronco is to reverse out of my flat level garage into my down sloped driveway. Clutch to first and the Hill Assist lets me get going up my driveway incline easily to get back out to a flat street. Right when I hit my flat street is when I experience the bucking and once I get up to a decent speed and hit 3rd gear it's all gone.

Who else that experiences the low gear bucking is driving on a slope or has the Hill Assist engage very early in your drive? I think this all might be software related to how the vehicle's Pitch is being measured. Hill Assist only kicks in as needed if the Pitch is outside of a certain threshold. I have tested with Hill Assist turned OFF and still continue to get rev hang sometimes in my 5th to 6th gear example. I haven't tested enough times to see if the low gear bucking completely goes away with Hill Assist off out of my steep driveway but will leave it off for a week and see if there's a difference.

Has happened to me too, but only when starting on an up-hill. Hill-assist is engaged, if I let out the clutch and press the gas to fast then it will "buck". I've learned to let the clutch out without giving extra gas. That seems to smooth it out.

 

[tourproto]

I would like to see anyone get their RPMs as low as 700 without stalling, even when not in gear. If your RPMs ever dip below 800 in a forced induction, DI, 4cyl engine you will feel why they named the truck Bronco as it bucks and comes to a complete standstill.

I wasn’t shifting that low. I was in the 1500rpm range.

 

[DaveInSA]

Mine does it on flat roads.

 

[redone17]

Mine does it on flat roads.

Same.

 

[Sparkherd]

Try turning the auto stop/start off ....

Scanning down the page, my pea brain read this as "Try turning the audio on/off..."
Shades of Cheech and Chong; "Have you checked the air in your tires lately?"

 

[Sparkherd]

I used Motul's Multi DCTF fluid for the RS transmission, as many others have done on the RS forums.

I think that's the stuff I was gonna put in my FieSTa, but now I'm *planning* on trading it for the Bronco, if it ever gets here, and I don't get boned.
Anyone looking for a Ford that hauls ass and gets 33 MPG?
2014 FieSTa, 49K miles, year old (1k miles) rotors, brakes, Michelin Pilot 4s.

 

[SPITmadFIRE]

I think that's the stuff I was gonna put in my FieSTa, but now I'm *planning* on trading it for the Bronco, if it ever gets here, and I don't get boned.
Anyone looking for a Ford that hauls ass and gets 33 MPG?
2014 FieSTa, 49K miles, year old (1k miles) rotors, brakes, Michelin Pilot 4s.

Please tell me you're not advertising your used car for sale on a thread about a very common 2.3L 7MT Bronco issue

Sponsored