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

[Karl_in_Chicago]

Mine does it on flat roads.

That's t-shirt material right there!

Sponsored

 

[Sparkherd]

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

I guess I am. Is that illegal?
Will I be banned for life?
I've already been banned for a week.
Yee Fn Haw!!!

 

[Giddyup Buttercup]

sounds like a sticky throw out bearing

 

[bradcd]

Alright I've had my Hill Assist feature turned off since Nov 3rd and am happy to report the unexplained bucking I was experiencing in low gears/cold engine has completely gone away. It's worth a try to disable the Hill Assist for anyone that's experiencing this. There is some understandable bouncing in throttle sometimes when starting from stop on a steeper incline but I attribute that to just the full weight of the vehicle against the clutch and finesse of accelerator pedal.

 

[Boreal]

Alright I've had my Hill Assist feature turned off since Nov 3rd and am happy to report the unexplained bucking I was experiencing in low gears/cold engine has completely gone away. It's worth a try to disable the Hill Assist for anyone that's experiencing this. There is some understandable bouncing in throttle sometimes when starting from stop on a steeper incline but I attribute that to just the full weight of the vehicle against the clutch and finesse of accelerator pedal.

This must’ve been addressed in an update, I have HSA enabled and haven’t had a buck for about 4-5 months now.

 

[ric42pars]

I am early receiver of a Bronco Black Diamond 2.3l manual in August 2021. I can say I've had the lurching on and off since new when cold. I didn't think much of it but lurching happens in first gear if I don't give it a minute or two to warm up before driving slowly through a parking lot or driveway. I figured it was just part of the warmup cycle. I'd just push in the clutch when it started. Feels like something with throttle control to me. Not clutch related. I've grown accustomed to let it go through it's warmup before taking off.

The bigger issue I've had lately since it has gotten cold here in NC is the throttle sticking in 1st and 2nd gear. This typically happens when cold and mostly clears up when warm. Again it feels like a throttle control issue. If I take off in first gear and get past 2000 RPM before shifting, the throttle seems to hang up at 2000 RPM or little higher (up to 2300 RPM maybe) and not back down for a couple seconds, then backs down. Seems to bother me most in first and second gear but I believe it does it in higher gears also. It's really annoying and glad I have a clutch to push in just in case. The throttle pedal feels kind of sticky so I tried pulling back on the throttle pedal with my toe when shifting. Didn't change anything. Still hung at RPM.

Checking in to see if anyone else has experienced the throttle hang up issue.

Thanks.

 

[SPITmadFIRE]

I am early receiver of a Bronco Black Diamond 2.3l manual in August 2021. I can say I've had the lurching on and off since new when cold. I didn't think much of it but lurching happens in first gear if I don't give it a minute or two to warm up before driving slowly through a parking lot or driveway. I figured it was just part of the warmup cycle. I'd just push in the clutch when it started. Feels like something with throttle control to me. Not clutch related. I've grown accustomed to let it go through it's warmup before taking off.

The bigger issue I've had lately since it has gotten cold here in NC is the throttle sticking in 1st and 2nd gear. This typically happens when cold and mostly clears up when warm. Again it feels like a throttle control issue. If I take off in first gear and get past 2000 RPM before shifting, the throttle seems to hang up at 2000 RPM or little higher (up to 2300 RPM maybe) and not back down for a couple seconds, then backs down. Seems to bother me most in first and second gear but I believe it does it in higher gears also. It's really annoying and glad I have a clutch to push in just in case. The throttle pedal feels kind of sticky so I tried pulling back on the throttle pedal with my toe when shifting. Didn't change anything. Still hung at RPM.

Checking in to see if anyone else has experienced the throttle hang up issue.

Thanks.

Throttle hang during warm up is almost certainly an emissions control mechanism -- this is pretty common amongst high-compression, forced-induction cars with manuals

 

[ric42pars]

Thanks for the reply. Good to know. So I'll just deal and be careful until warmed up. Guess I need an electric Eco-friendly vehicle.

 

[ric42pars]

Throttle hang during warm up is almost certainly an emissions control mechanism -- this is pretty common amongst high-compression, forced-induction cars with manuals

Do you think the lurching is related to this same issue?

 

[SPITmadFIRE]

Thanks for the reply. Good to know. So I'll just deal and be careful until warmed up. Guess I need an electric Eco-friendly vehicle.

It’s definitely a weird quirk to get used to if you’re not accustomed to newer turbocharged engines, but the ECU should do a good job of dropping the revs once you start putting some load on and shifting into gear

 

[SPITmadFIRE]

Do you think the lurching is related to this same issue?

I don’t think so, but my data is all anecdotal. The lurching still seems like a throttle map issue that happens when warming up — mine never happens when I start the truck from cold, or when still hot from last start. It only happens when the truck is somewhat warm, but not fully warmed up (oil temp between 100F and 150F).

 

[ric42pars]

It seems to be worse for me when oil temp is below 100. I fixed it on the way home from work today. It is not noticeable if you rev the crap out of it and drive it like you stole it. That was a fun drive.

 

[Gnomad]

I had something like this happen when I changed my tires from stock to 285/75/16's, but after completing all of the forscan recalibration steps, especially the RCM relearn, it went away. Might be something to try if it's chronic and won't go away.

 

[Gnomad]

I am early receiver of a Bronco Black Diamond 2.3l manual in August 2021. I can say I've had the lurching on and off since new when cold. I didn't think much of it but lurching happens in first gear if I don't give it a minute or two to warm up before driving slowly through a parking lot or driveway. I figured it was just part of the warmup cycle. I'd just push in the clutch when it started. Feels like something with throttle control to me. Not clutch related. I've grown accustomed to let it go through it's warmup before taking off.

The bigger issue I've had lately since it has gotten cold here in NC is the throttle sticking in 1st and 2nd gear. This typically happens when cold and mostly clears up when warm. Again it feels like a throttle control issue. If I take off in first gear and get past 2000 RPM before shifting, the throttle seems to hang up at 2000 RPM or little higher (up to 2300 RPM maybe) and not back down for a couple seconds, then backs down. Seems to bother me most in first and second gear but I believe it does it in higher gears also. It's really annoying and glad I have a clutch to push in just in case. The throttle pedal feels kind of sticky so I tried pulling back on the throttle pedal with my toe when shifting. Didn't change anything. Still hung at RPM.

Checking in to see if anyone else has experienced the throttle hang up issue.

Thanks.

That sounds a bit like "icing" maybe? Lower temps and higher humidty can cause an ice buildup in the intake at the throttle plates, the low pressure area.

 

[redone17]

20k+ and this still happens once in a while.

I think I’ve narrowed it down to only happening when the vehicle is warmed up (perhaps not fully) and then off for some time (hour or less) and I go out for another drive. Water temp is generally at 1-2 bars (not fully warmed up). Usually 2nd gear/1200-1500 RPM. Take foot off gas - goes away. Continue.

Sponsored