Is anyone else experiencing a jerky acceleration? Seems like when the turbo kicks on there's a big boost that throws my passengers into their seat. Is this something that we just have to get accustomed to or is there a way to dial this down?

Other than that loving the car!

 

Just give it two more weeks. Everything will be fine.

 

P400 or 300? My 400 has very poor power delivery, in the way you describe. But it’s not classic turbo lag, best I can tell. It seems to be the Drive By Wire programming. Pull out, give it the amount of throttle you would expect based on 40 years of driving scores of different cars, and get a tepid dawdling along. Look in RVM, see approaching traffic, panic a little, give it more gas, then VROOM! it takes off.

I corrected this with a SprintBooster module on my 2014 3.6 Wrangler. Going to try that or something similar on this Defender. Problem went away immediately and completely.

I’ve owned DBW (electronic throttle) cars since my 2002 911 Turbo and it doesn’t have to be this way. Probably has to do with gaming the EPA and/or Euro fuel economy testing. Annoying as hell in an automatic, and downright undrivable in a manual (like my Jeep.) I could never time the clutch let-out. After driving it a little, I’d get used to it and be okay, but then when I’d get back into my Porsche which didn’t have the delay, I couldn’t drive it.

Doesn’t seem to be one for Defender yet; there are other people in this space — I’ll research it in a little bit.

SprintBooster

 

@NoGaBiker that sounds ABnormal for a P400. The two I've driven have been quite linear (for a turbo) and predictable, especially for an auto trans with drive by wire.

I've had similar jerkiness with other turbo cars on a tank of bad gas. Pulls timing with a big delay then irregularly gives you full boost.

 

Yeah I agree it sounds like sensitive DBW response/programming.

That said I got used to it quickly.

Then again I don't have any problem with the throttle in my Jeep or slipping the clutch. Actually I can walk my Jeep with the clutch in tight spots.

I've also heard similar complaints on DBW motorcycles over the years. I don't share them.

So I think it's definitely a conquerable issue.
issue.

Edit - PS I think it's made worse if you use the auto brake hold.

 

Thanks, Kev, for the reminder. Every time I drive the LR I say bad words to myself about how I hate that sumbitch, but I can never remember when I get home to delve back into the menus and turn it off. I’m doing it right now. Don’t know how much it will help the laggy throttle but at least it will be gone. I’ll report back.

As for your ability to work the Jeep’s clutch without issue, do you have other manual cars you drive back to back with it? That was my problem. I’d jump in the Jeep and practically stall it (or actually stall it) because I was releasing the clutch too soon, based on the usual relationship of right foot and left foot (throttle and clutch); it’s a delicate balance (as witnessed with every new clutch-user in the world) that you get used to and never think about again. But when the throttle “holds onto” the power delivery a second or so before obeying your right foot, it throws your 30-years-of-driving-manual timing off. If you only drive a Jeep, you get used to it within a few minutes and probably never think about it again.

But when I would park the Jeep and jump into my 911 or GT4 or MINI, my new “Jeep specific” clutch timing muscle memory would cause me to delay releasing the clutch for that extra second or so, and now instead of stalling, I’d rev the motor to 4000 rpm before letting the clutch out. So I’d have to relearn the proper timing again.

Putting the SprintBooster in solved it and all was good for the next 7 years. My buddy has a 2006 TJ Rubicon 4.0 with a throttle cable and it didn’t have the lag at all, so it’s not “a Jeep thang.”

 

Though I think both my wife and I have had more manuals than autos over our lives, my Jeep has been the only manual car (obviously we still have our fleet of bikes) in the last decade.

I definitely had growing pains as I got used to it the first year or so. And not just the throttle but more that horrible shifter.

But it's not like I had any problem jumping to another manual, like that week+ as COVID broke out around the world when we flew into Dublin and picked up a manual, diesel, right-hand drive Tiguan and drove out into the roundabouts of Ireland at 5:00 AM.

Throttle and clutch management were, luckily, not a worry, well not as much as keeping left and shifting with my left hand lol. It didn't help that the rental had something like only 17 miles on it when we picked it up. No pressure.

 

My Defender has the auto park feature switched on when I picked it up from the dealer. Really annoying driving home in heavy traffic. At first I did not know what was wrong but then noticed the “Hold” message in the instrument display. Why it would be on my default I do not know. Actually I do not know why it would even be classed as a feature. When I got home I turned it off. Pulling away from a standstill now very smooth.

 

I drive both our P400 Defender and V8 LR4. Obviously the LR4 acceleration is very linear. P400 definitely has a point where the turbo or supercharger kicks in and you get a surge of acceleration. I really noticed it at first when new but not so much anymore. I think you adapt to the P400 power delivery over time. I tend to press the gas harder from a dead stop then let up around 20 mph when I know the surge is coming. And yes, turn off that stupid brake hold feature unless you are rock climbing.

 

@NoGaBiker My experience has been similar to yours. My previous car was the Range Rover Sport and that had a very linear correlation with pedal pressing translating to an increase in the car's acceleration. The Defender feels like the first 15 mph are dangerously slow, and then once the turbo kicks in you get this massive spike in acceleration. Really only matters in stop and go traffic, or when turning with oncoming traffic. Would be curious if that SprintBooster helps once it comes out. Will have to check the auto break hold. Didn't really notice that before but will definitely take a look today