Author Topic: Reluctance of the Mk3 CVT to change gear  (Read 4520 times)

Kenneve

  • Approved Member
  • *
  • Posts: 993
  • Country: gb
  • My Honda: 2023 Jazz Advance e-HEV, Red
Reluctance of the Mk3 CVT to change gear
« on: June 12, 2017, 08:19:32 PM »
Hi Guys
Has anyone had a problem with the CVT box not changing down when required.
EG lets say you doing a steady 30mph and you want to briskly accelerate to overtake someone.
I am finding that box will not change down unless i put the accelerator to the floor and even then it sometimes won't react.
The engine appears to stay within the Atkinson cycle part of the rev range, yes I can use the paddles to change down perhaps 2 gears, but that should not be necessary.
Normal acceleration from a standing start is fine, the problem only occurs around the 30-40mph range.
I just thought I would ask you guys, before asking my dealer for advice.

trebor1652

  • Approved Member
  • *
  • Posts: 748
  • Country: gb
  • Fuel economy: 64.7 mpg
  • My Honda: Crosstar Crystal Red Two Tone
Re: Reluctance of the Mk3 CVT to change gear
« Reply #1 on: June 12, 2017, 08:26:26 PM »
I find the same.
The paddles definitely get the required result better than stamping on the accelerator.
Or you can always try S mode.

Sent from my XT1039 using Tapatalk


andruec

  • Approved Member
  • *
  • Posts: 936
  • Country: gb
  • My Honda: (ex)Jazz Mk3 EX-t
Re: Reluctance of the Mk3 CVT to change gear
« Reply #2 on: June 12, 2017, 09:33:34 PM »
Sometimes, yes. It happened a lot when I first got the car but in the 18 months since I've mostly adapted to it. I've found that it's possible to move the accelerator sharply down but not actually to the floor to trigger a 'mini-kick down'. I use it to jump the car straight to 3,000 rpm when pulling away.

It still sometimes doesn't react properly but it's less common now and might be due to my shoe catching the side of the wheel arch. I don't think I've ever had it on the open road though. For me it's mostly been when pulling away from roundabouts. Then again I rarely need to accelerate quickly on the open road. There rarely seems any point in overtaking most of the time these days.

It's always amused me that despite generally driving low-powered cars (including 1 litre Mini Metros) I often out accelerate most other drivers at junctions. I don't burn rubber but I do consider around 3,000 rpm to be the optimal point. A good compromise between peak fuel efficiency (wide open throttle) and the practical considerations of driving on today's roads. I prefer a rapid(ish) burn at 3,000 rpm then a no throttle glide down to stationary over a continuous slow acceleration and use of brakes.
« Last Edit: June 12, 2017, 09:42:08 PM by andruec »

VicW

  • Approved Member
  • *
  • Posts: 1441
  • Country: england
  • My Honda: 07 Plate Civic 1.8 i-Shift.
Re: Reluctance of the Mk3 CVT to change gear
« Reply #3 on: June 13, 2017, 03:44:25 PM »
Or you can always try S mode.

I have always used the 'S' mode on my CVT boxes quite extensively.
It makes the engine and pull away much livelier when joining roundabouts and main roads from side roads and obviously when overtaking.
Yes the engine will rev higher but it won't blow up, the i-VTEC engines thrive on revs.

Vic.

Downsizer

  • Approved Member
  • *
  • Posts: 853
  • Country: gb
  • My Honda: Jazz 1.3 SE cvt - Feb '16 - Blue
Re: Reluctance of the Mk3 CVT to change gear
« Reply #4 on: June 14, 2017, 02:31:25 PM »
I've been looking for this problem but I can't find it.  At a steady 30 on the flat, in D not S, the rev counter shows 1200. Flooring the accelerator results in an increase to around 4500 and rising with acceleration, within about a second.  I don't think I could do it any quicker in a manual, starting from top gear.

andruec

  • Approved Member
  • *
  • Posts: 936
  • Country: gb
  • My Honda: (ex)Jazz Mk3 EX-t
Re: Reluctance of the Mk3 CVT to change gear
« Reply #5 on: June 14, 2017, 04:05:11 PM »
I've been looking for this problem but I can't find it.  At a steady 30 on the flat, in D not S, the rev counter shows 1200. Flooring the accelerator results in an increase to around 4500 and rising with acceleration, within about a second.  I don't think I could do it any quicker in a manual, starting from top gear.
I've never known it not accelerate when pushed flat but the OP actually wrote:
EG lets say you doing a steady 30mph and you want to briskly accelerate to overtake someone.
I am finding that box will not change down unless i put the accelerator to the floor and even then it sometimes won't react.
The bit in italics is an exceptional thing, not the norm.

The OP's main complaint is that when you just want to go a bit faster it sometimes won't. What I have encountered quite a lot is that if you're leaving a roundabout (maybe 20mph) and press the accelerator a bit as you would in most other cars almost nothing happens. If you keep gradually depressing the accelerator there will come a point when you get a sudden surge as the engine wakes up. I found it quite irritating when I first got the Jazz. I don't know if what I do with the pedal is a kickdown or if I'm just pushing it straight to the point where it would wake up anyway.

As regards the OP's italicised comment I wonder if that relates to two stage accelerator operation? Right at the bottom of its throw there seems to be a switch. I have noticed that if you want real acceleration you have to press far enough to activate this switch. When you do that you should feel a distinct 'click' through your feet.

I don't know the purpose of the switch but as the OP suggested I think this all relates to the dual mode nature of the engine. It would rather stay in Atkinson mode so unless you make it clear that you want to get moving that's where it will be. And Atkinson mode can barely pull the skin off a rice pudding.
« Last Edit: June 14, 2017, 04:09:31 PM by andruec »

guest1372

  • Guest
Re: Reluctance of the Mk3 CVT to change gear
« Reply #6 on: June 14, 2017, 05:18:17 PM »
I wonder if that relates to two stage accelerator operation? Right at the bottom of its throw there seems to be a switch. I have noticed that if you want real acceleration you have to press far enough to activate this switch. When you do that you should feel a distinct 'click' through your feet.
There's no switch to speak of but TPSA & TPSB are two position sensors at the pedal*.  All they are doing is sending a variable voltage back to the ECU/PCM.  The internal maps determine throttle opening & CVT positioning depending on these signals plus a whole bunch of other sensors & variables.
Any physical click or change in force is probably just down to the pedal return spring.
--
TG

* For safety there are two sensors whose outputs must correlate.  These are 'hall effect' magnetic encoders rather than a physical resistance track like a volume control, the magnet and sensor have no direct contact and are sealed. The sensor is also pre-calibrated to account for variance in magnetic flux density.  http://www.delphi.com/manufacturers/auto/sensors/chassis/noncontact

andruec

  • Approved Member
  • *
  • Posts: 936
  • Country: gb
  • My Honda: (ex)Jazz Mk3 EX-t
Re: Reluctance of the Mk3 CVT to change gear
« Reply #7 on: June 14, 2017, 06:24:35 PM »
sical click or change in force is probably just down to the pedal return spring.
I've felt it on Jazz courtesy cars as well. It's a very definite 'click'. In fact I might put it even more strongly and say that it's as if there's a deliberate notch at the bottom of the pedal travel that you have to push past. It wasn't present on the previous models (and I've owned all three).

Kenneve

  • Topic Starter
  • Approved Member
  • *
  • Posts: 993
  • Country: gb
  • My Honda: 2023 Jazz Advance e-HEV, Red
Re: Reluctance of the Mk3 CVT to change gear
« Reply #8 on: June 14, 2017, 08:29:05 PM »
Hi Guys
Many thanks for the comments so far.
I have to say, until i read Andruec's comments re the 'notch' at the end of the pedal travel, I had no idea such a notch existed.
Yes I can feel the notch now, but I never get to that position in normal driving.
I'm fairly sure that the reluctance condition did not exist when the car was new, i only noticed it earlier this year, after a 6 week layoff in hospital.
I think i will have a word with my dealer, since it's not just me, and see what he says.

Downsizer

  • Approved Member
  • *
  • Posts: 853
  • Country: gb
  • My Honda: Jazz 1.3 SE cvt - Feb '16 - Blue
Re: Reluctance of the Mk3 CVT to change gear
« Reply #9 on: June 15, 2017, 12:37:41 PM »
I've felt it on Jazz courtesy cars as well. It's a very definite 'click'. In fact I might put it even more strongly and say that it's as if there's a deliberate notch at the bottom of the pedal travel that you have to push past. It wasn't present on the previous models (and I've owned all three).
Yes - I'ld not noticed it before, and I very rarely need to floor the accelerator, but there is a clear increase in pressure required to travel the last bit.  It must be telling the system something, and it certainly downshifts the gearing.

Tags:
 

anything
Back to top