Diesel acceleration query

Forum for Engine, Exhaust, Drivetrain, ECU
Deleted User 1571

Post by Deleted User 1571 »

Keep the revs at 1500 or above to avoid a torque curve that drops like a stone. Its good practice on all four cylinder engines, including petrol, anyway. The stable working range of high speed light engines usually spans from around rated maximum down to 1500. Below 1500, besides the torque curve issue, the engine becomes unstable under load and extreme stress is imposed on crankshafts. It may even hint at this in the driver's manual.
The other indication for this is the gear change indicator in the dash which will advise a down change when pulling hard under 1500.

Should you drive in this way, you will find near zero lag of any kind and you will be in the optimum torque range for acceleration. I find that it is very easy do drive most of the time with revs between 1500 and 3000, when I can easily achieve 55mpg and often 60. Town traffic does require lower revs quite often, but a steady foot and fairly gentle acceleration until 1500 makes all the difference. High revs are seldom required to drive a diesel quite quickly, but the K9K is quite lively. It does suffer from low start-off torque compared to many engines though, so it can be quite easy to stall from a standing start.

mikeyc1
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Joined: Fri Apr 29, 2016 9:07 pm

Post by mikeyc1 »

I've just got a 1.6dci tekna xtronic and whilst generally I really like the car I just cannot bare the sluggish performance off the line, it borders on dangerous ! the lag is way too much, Yes you can get get used to it and predict gaps in traffic but when it comes to needing power and energy quick then forget it. it's a 2015 model ,Is there any fixes for this? I don't think I can live with a car like this, roundabouts are just silly, the head says go but the car says yawn .....wait then a load of torque too late..
jstallan
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Joined: Mon Mar 23, 2015 2:16 pm

Post by jstallan »

I suppose you could look at getting the ECU remapped ?
2014 (64) QashQai 1.5 dci Tekna in Blade Silver
mikeyc1
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Joined: Fri Apr 29, 2016 9:07 pm

Post by mikeyc1 »

I've booked my car in for a Viezu remap on the 15th. Had many a car remapped in the past so I'm comfortable with the process. Hopefully looking at a nice torque increase and it may help the hesitant nature of the engine from Idle, I'll report back on here with the outcome
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Gel
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Location: Thames Valley UK
Qashqai Model: Mk.2 Qashqai - J11 (2013–2017)

Post by Gel »

Should have picked manual box perhaps?
2014-19 J11A-14 1.5dci Ink Blue Tekna owner; now departed for a Mazda CX-5 GT Sport Nav, 2.0L Petrol :D
mikeyc1
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Joined: Fri Apr 29, 2016 9:07 pm

Post by mikeyc1 »

Wife is a bit "special " she can only drive autos so it had to be the cvt, coming from a golf gti with dsg auto box it was fantastic , some autos are amazing , just not the cvt so far! Maybe it'll grow on me , let's see how it goes
craigstekna
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Joined: Mon May 30, 2016 10:55 am

Post by craigstekna »

Dont all QQ's have CVT boxes?
J11 - QQ 1.6 130 Dci Automagic Tekna, Pearl white, Sept 2014 :D FULL LED upgrade to all interior/exterior lights, china crossover pack, mud-flaps, sill guards and hood deflector
mikeyc1
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Joined: Fri Apr 29, 2016 9:07 pm

Post by mikeyc1 »

Just had my car remapped by this guy

http://www.remappingsussex.co.uk/

Very nice increase in torque which comes in lower down the Rev range, throttle response has also improved. Torque is now around 380nm. Very pleased with the way it's driving now:-)
DaveBerlin
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Qashqai Model: Mk.2 Qashqai Facelift - J11b (2017–2021)

Post by DaveBerlin »

We have a petrol, but has anybody raised the question with Nissan regarding the "Guarantee" after "Re-Mapping" an engine that could be spotted at a Service by a Nissan Technician (Dealers can be a little Anti) - Just interested not a criticism Dave ;)
11.19/1.3L/160PS/Tekna+/DCT/PrOPILOT/KAD Gun Metallic/Trunk Lower Finisher/Rear Glass Finisher/Ambient Lighting-LED’s Innen/Entry Guards Illuminated/Sport Pedals/Front Styling Plate/LED No.Plate/Chrome Door Handles/Rear Valance/Giacuzzo Alloys + Falken
gvmdaddy
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Post by gvmdaddy »

DaveBerlin wrote:We have a petrol, but has anybody raised the question with Nissan regarding the "Guarantee" after "Re-Mapping" an engine that could be spotted at a Service by a Nissan Technician (Dealers can be a little Anti) - Just interested not a criticism Dave ;)
Could also be an issue with your insurance company
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