60mph, sharp intake of breath?

All Volvo XC40 related discussions
Post Reply
RealGoneKid
Posts: 34
Joined: Sun Sep 06, 2020 7:15 pm

Post by RealGoneKid » Wed Jul 21, 2021 8:21 pm

When reaching exactly 60mph, at the first attempt, on each and every journey, my PHEV reacts by what I can only describe as taking a sharp intake of breath. Basically a noticeable drop in speed before pick up. Like a slow gear change, but not.

Same journey if I do it again, i.e. increase speed from below to above 60, no issue.

Usually when on electric power only but not always. Different roads, no speed sign reaction or lane changing going on. No other road condition changes.

Anyone else notice this?
T5 Recharge PHEV MY21, R Design Pro, Glacier Silver, Lounge & Climate packs. New purchase from dealer stock Oct 20. Ceramic Coated after purchase.

User avatar
m@rk
Posts: 171
Joined: Fri Dec 11, 2020 10:06 pm
Location: Lincolnshire, United Kingdom

Post by m@rk » Wed Jul 21, 2021 8:59 pm

It’s a feature!

It’s horrible!

It’s not a fault according to Volvo!

In some countries they put this in the manual (note Twin Engine was what they called it before Recharge). Remember it’s a dual clutch gearbox:

Questions that may arise about changing gear in electric operation.

When driving the XC40 Twin engine, it sometimes seems as if I lose power when accelerating between 80-90 km/h, why?
In the XC40 Twin engine, the electric motor is installed in combination with the transmission. When the electric motor is used, it starts in second gear and changes to fourth gear at high speeds (80-90 km/h).
When changing from second to fourth gear, at the same time as accelerating, the engine loses power, i.e. the torque from the motor is reduced for short period in order for changing gear to be possible. This behaviour is normal.

Why does the car need to change gear?

By using a low gear at lower speeds, the electric performance can be improved when starting and driving at low speed. This means that the power from an internal combustion engine is not needed in the same way as in a hybrid.
By using a high gear at higher speeds, the electric drive and power can be used for higher speeds. This can contribute to a lower energy consumption at higher speeds.

Sometimes it seems as if the motor is losing power, why?

The power transmission will always aim to change gear from second to fourth in electric operation whenever the driver releases the accelerator pedal (halfway or fully). This means that the driver will hardly notice the gear change. However, if the driver constantly accelerates from lower speeds up to approx. 90 km/h, changing gear will be noticed according to the description above.
When speed is reduced, downshifting from fourth to second gear will hardly be noticed since there is no need for extra power during downshifting. This means that changing gear can take place without any power disruption.
Last edited by m@rk on Thu Jul 22, 2021 8:45 am, edited 1 time in total.
XC40 T5 Recharge Inscription Pro - Denim & Blonde

Image

morganj
Posts: 152
Joined: Wed Jan 08, 2020 7:50 am

Post by morganj » Wed Jul 21, 2021 9:06 pm

Have noticed this a few times in Pure mode on one particular stretch of road.

I have put it down to how I understand the gearbox from some early googling before purchase.

As I understand it the electric motor is connected to the shaft on one side of the dual clutch gearbox and delivers its power trough what is essentially 2nd or 4th gears. So my conclusion is you (and I) are feeling the gear change from 2nd to 4th.

A good description is found here;

https://www.caranddriver.com/news/a1534 ... explained/
XC40 T5 Recharge MY21 | Versatility | Driver assist| Techic | Light | Semi-auto Park assist

Ian Almighty
Posts: 16
Joined: Thu Jul 01, 2021 4:09 pm

Post by Ian Almighty » Thu Jul 22, 2021 9:07 am

Actually the caranddriver URL is very good and explains the reason why gears 2 and 4 are used on battery power.
Volvo XC40 T5 Inscription Recharge (PHEV) in Glacier Silver

allyburt
Posts: 4
Joined: Thu Aug 26, 2021 12:11 pm

Post by allyburt » Thu Aug 26, 2021 3:24 pm

Why don’t I feel it every time I accelerate through 59 mph?

---
Posts: 55
Joined: Wed Aug 19, 2020 3:10 am

Post by --- » Wed Apr 20, 2022 2:28 am

Yes, I get this sudden loss of power at about 94kph. Seems to occur the first time on each start, when going from say 0-100kph, in pure electric mode. It's repeatable, and very annoying, especially if you're trying to overtake at that moment when you loose power.
MY21 XC40 T5 Twin Engine Recharge
MY21 XC40 T4 Inscription
(MY20 XC40 T4 Inscription, rejected & now returned!)

bigboots
Posts: 21
Joined: Mon Apr 05, 2021 10:05 am

Post by bigboots » Wed May 11, 2022 10:17 pm

Yep know that feeling, scared the absolute life out of me, now it’s just a case of ‘meh, here we go again’ before it goes off like a scolded cat

Post Reply

  • You may also be interested in...
    Replies
    Views
    Last post