From time to time I get a 'surge' of power when running at low speed whilst keeping a 'steady' throttle - it is disconcerting until you get used to it - any ideas why it does it ?
Technical Surge of power at low rev's
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Technical Surge of power at low rev's
buzzwoody
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I get the same, although I feel it is only when the engine is cold. Someone said it was the Flywheel? used to smooth out the running with a Diesel Engine. Got used to it now - does seem constant, not getting more frequent.
Youre doing well to get a surge of anything in a Doblo 
I love mine really.
I love mine really.
Thanks for the thought but no, definately a surge from the engine with diesel being injected to restore what presumably the EMU feels is necessary.
Anyone got an insight as to who is on the right track?
Might be worth changing the air filter.
Might be worth changing the air filter.
Only done 8k miles and looks new so not that I suspect. I feel that it is a EMU (if thats what they are called Engine Management Unit) giving the engine a boost cos I am 'labouring' same trying to tweak an extra mpg
- will speak at the garage next time it is serviced to see what they can suggest .Italian tuning remember!
Drive it decently hard or you'll get all sorts of bunging up problems.
Never labour the engine either.
It's run in now, so drive it hard regularly and you'll have no trouble.
Use the revs, and when on a long journey don't be afraid to sit at high speed for a long time; after that it will be as sweet as a nut.
And don't forget to let it idle for a while before switching off the engine.
Drive it decently hard or you'll get all sorts of bunging up problems.
Never labour the engine either.
It's run in now, so drive it hard regularly and you'll have no trouble.
Use the revs, and when on a long journey don't be afraid to sit at high speed for a long time; after that it will be as sweet as a nut.
And don't forget to let it idle for a while before switching off the engine.
Thanks for that - but - and there is always one - I was always taught that a diesel engine is designed to give max torque at low revs - as this engine does with max torque at 1750 rpm. Fuel efficiency is how I drive this leaving my two wheel times to making progress
Any harder driving without need i.e. pulling uphill or heavily loaded is clearly a waste of fuel once the engine has reached its max torque - or has the Italian influence brought about a complete u turn in engine design etc?
Any thoughts will be appreciated.....:idea:
Thanks for that - but - and there is always one - I was always taught that a diesel engine is designed to give max torque at low revs - as this engine does with max torque at 1750 rpm. Fuel efficiency is how I drive this leaving my two wheel times to making progress
Any harder driving without need i.e. pulling uphill or heavily loaded is clearly a waste of fuel once the engine has reached its max torque - or has the Italian influence brought about a complete u turn in engine design etc?
Any thoughts will be appreciated.....:idea:
I've had Diesels for many years now and it is true that old Diesel engined cars were all torque and not much else and I used to drive them accordingly, but my Doblo is my first modern Diesel and it's completely different to drive.
I find it needs to be driven within the peak "power band" rather than using the low end torque.
I change gear generally around 3000 rpm and cruise between 2000 and 2500 rpm. I find I have to do this or the engine isn't producing enough power.
Some of my old Diesels would quite happily trundle up hills at about 1000 rpm.
Modern Diesel engines are designed completely differently and are supposed to appeal to die-hard petrol engine fans...imo.
The turbos have a wider power band and are designed to rev, and they need to get hot to work the new DPFs. If they are never extended sufficiently they will clog up and cost a fortune to fix, more than negating any fuel cost saved.
I doubt if much fuel really would be saved either. My 1.9 thrives on long hard runs, and economy is more dependent on wind direction than anything else. A steady 80-90 for hours on end, on the continent, still gives 45 mpg +, which I think is fine. And I make sure I put my foot down to maintain these speeds up long inclines. There is one in Belgium on the route to Luxembourg which goes on for ever.
I doubt if much fuel really would be saved either. My 1.9 thrives on long hard runs, and economy is more dependent on wind direction than anything else. A steady 80-90 for hours on end, on the continent, still gives 45 mpg +, which I think is fine. And I make sure I put my foot down to maintain these speeds up long inclines. There is one in Belgium on the route to Luxembourg which goes on for ever.
Modern diesels like the Fiat JTD amd Multijet make much use of emission control devices such as Exhaust Gas Recirculation EGR and these very quickly block up with carbon, the best way to keep these clear is to occassionally give the engine a good workout.
It has nothing to do with torque or economical driving but just occassionally you need to thrash modern diesels to clear their inards out.
Alternatively you can use an additive such as Millars Diesel Sport which I use even in my new Doblo and this keeps everything running perfectly.
My mate has a Seat Leon with VW's ultra modern 2.0 TDi engine and these can be very bad for clogging its EGR. He has been told by VW that cars driven mainly round town often give problems but rarely have problems reported from motorway mileage cars.
It has nothing to do with torque or economical driving but just occassionally you need to thrash modern diesels to clear their inards out.
Alternatively you can use an additive such as Millars Diesel Sport which I use even in my new Doblo and this keeps everything running perfectly.
My mate has a Seat Leon with VW's ultra modern 2.0 TDi engine and these can be very bad for clogging its EGR. He has been told by VW that cars driven mainly round town often give problems but rarely have problems reported from motorway mileage cars.
Interesting response
. By thrashing a diesel surely you use more fuel creating more carbon bringing about earlier clogging :bang:.Have you worked out costs of Millars v the more expensive diesel with the higher rating that is also supposed to assist in keeping the engine 'clean' and in good working order?
