Engine & Gearbox Hot Turbos - allow to tickover before switching off

Discussion in '9th Generation (2012-2017)' started by poor1, Saturday 28th Feb, 2015.

  1. poor1 Junior Member ☆ ☆ ☆ ☆ ☆

    Just bought a 2012, 2.2 diesel (manual) and it's a very sophisticated vehicle. In some ways too clever for it's own good. Not bothered by the the high spoiler at the back, although it was a feature which put me off for a long time.
    What I don't like is the stop/ start feature. Not only from a wear and tear point of view, but going against all the perceived wisdom of allowing a turbo engined vehicle to tickover before switching off, particularly after a hot run, to obviate the oil circulating in the turbo bearings frazzling and to cool off before stopping the engine.
    My Audi TT has a water cooled turbo and a an electric run on pump to circulate the coolant for ten minutes after switching off the ignition, The Golf TDI manual stresses the importance of allowing the engine to tick over for at least a minute before switching off.
    I took the opportunity of asking a Honda workshop foreman about this and he looked blank as though it have never occurred to him and simply replied that Honda must have thought about it. He maintained that there is no need to follow this procedure with a Honda engine
    Any observations from anyone technically knowledgeable please?
    - - - Updated - - -
    I did mean to add on the above posting that I do of course appreciate that it is possible to switch the stop/start off at the beginning of every journey, but I would like to know whether it is possible to switch it off permanently . The Honda foreman who had never been asked the question before stated catagorically that it was not possible. Any views please?.
  2. Nels Moderator Staff Team

    Hello and welcome to HK :tut:. :welcome:
    It's worth a few minutes to start a thread in the 'Introduce Yourself' section.

    Congratulations on your Civic. :Niceone:
    It's also worth popping her into the 'Club Garage'. That way, she will show as a link at the bottom of your posts. It helps us help you.

    I can't profess to know a great deal about the stop-start system, but I'm sure there's someone here that can help you.

    Whilst I understand your concerns for cooling down the turbo, I'm sure Honda have taken this into account. They tend to thoroughly test things before they go into production.
    We will wait and see what the other have to say.
  3. leonard Senior Member ★ ★ ☆ ☆ ☆

    leonard london
    The foreman must be a tool.
    Rule of thumb on every turbo as far as I know is, idle on startup for one minute to allow the oil reach to the turbo and the same before stop to allow the turbo to slow down to normal speed.
    As for Start/Stop function ,can't help as you mine is auto without it (thankfully)
  4. Nighthawk Guest

    United Kingdom Richard T Milton Keynes
    That whole cool down this was mainly for turbo petrols as their turbos run hotter than diesels. You can pretty much drive the daylights out of a diesel, and you won't get the turbo up to the same temperature as a petrol. I always let mine idle for a minute before driving off if its a cold start, but thats more because old habits die hard and I learned to drive with carbs which are more fussy (showing my age at all here??)

    I drive quite a range of diesel cars, alot of the time they are from a cold start and are redlined pretty much straight away, driven hard for 10 minutes, and then instant turn off. Never had a turbo go pop on me. Admittedly, have blown pistons out the side of a diesel, blown gearboxes, shocks etc, but never a turbo. Luckily, none of the cars were mine.
  5. leonard Senior Member ★ ★ ☆ ☆ ☆

    leonard london
    This is what happen when you switch the turbo engine off without waiting to idle.

    it will continue to burn the oil until dry.
  6. Nighthawk Guest

    United Kingdom Richard T Milton Keynes
    It does that when you overfill - the negative pressure sucks the oil back up through the engine, it hits the turbo and then it runs it dry. Thats not a result of not letting the turbo cool down.
  7. poor1 Junior Member ☆ ☆ ☆ ☆ ☆

    Thanks for all your interest. The scenario described and illustrated by leonard only happens with diesel engines, its where the engine consumes it's own oil which does not happen with petrol engines. Quite rightly this phenomeom can be caused by the turdo failing and the oil being inducted into the engine and is usually catastrophic. The vehicles I was referring to my in original post on the subject, the Golf is a diesel and the Audi is petrol and I have nearly always adhere to this principle of allowing the engine to tick over, but my son who runs a Golf TDI with a round trip of 160 miles a day never bothers and it's still going strong at 150K.
    Nighthawk likes this.
  8. Nighthawk Guest

    United Kingdom Richard T Milton Keynes
    The diesel overruns are very common with taxi drivers - because their cars are always maintained to a top notch standard :Whistle:

    The turbos on diesels do not run as hot as petrols, no harm in letting it cool down, but unless you are ragging the daylights out of it till the very last moment, its not as sensitive as a petrol in my experience.
  9. cchris77 Junior Member ☆ ☆ ☆ ☆ ☆

    Germany Chris Munich
    I would not be so much worried about the turbo. As you can hear it while running, it doesn't need so much time to slow down. Normally from such a rotation speed it would need it, but it pushes air as well, and that should slow it down quickly. Anyway, as long as it runs it needs oil be pumped, that's true, therefore I would not be worried but a little careful, or at least avoiding extreme situations of full power followed by engine stop.

    I am also very interested if someone could completely disable the annoying start/stop system. At least from my perspective the start/stop system does only useless starter wear which we will need to pay later. The economy and the pollution reduction are considerably higher some other ways, it is completely irrelevant in practice (only my opinion).
    I asked in two Honda services in two different countries if they can turn it off but I had no success.

    On the other hand I wonder how is it healthier for the engine when running in a city for a short distance: to let the start/stop system do its job and arrive at destination with a cold engine (or at least not fully warmed) - that means to allow several cold engine starts and having a potentially negative impact on DPF, or on the other side to switch the system off and let the engine warm up quicker.

    Because I didn't introduce myself, I drive a 2014 Civic 1.6 I-DTEC Tourer and my wife a Jazz 1.2.
    AccordCU2 likes this.
  10. Nels Moderator Staff Team

    Hi and welcome @cchris77 :welcome:

    Please tell us more about yourself in the 'Introduce Yourself' section.
    Congratulation on having 2 Hondas in your family.:Niceone:
  11. poor1 Junior Member ☆ ☆ ☆ ☆ ☆

    Chris: I totally agree with you as regards your observations regarding the stop/start. BMW have introduced an option in their software to allow this feature to be modified to 'last user' which in effect permanently disables the feature. Judging by the number of people who have bothered to comment on the various forms it is widely regarded as an irritating feature and it is just a pity that Honda do not listen.
  12. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
    Honda have to be seen to be trying to appease environmental issue hence features such as Stop/Start. It's not just Honda, pretty much all manufactures. Even the top end luxury marques have it on their cars.

    I'm sure there is a button on the Hondas that can be pressed to disable this system. I can't remember if you have to press it every time you get in though.
    Last edited: Sunday 1st Mar, 2015
  13. poor1 Junior Member ☆ ☆ ☆ ☆ ☆

    Appeasing is the right word because in reality it is more of a hindrance than a necessity. Cynically you could say that over time the wear and tear on cars using this feature will amount to millions of pounds and the unnecessary wear and tear and replacement of parts will far outweigh any environmental benefits.
    It's true that Honda is not the only culprit and yes it is possible to switch the feature off on each individual journey. This flies in the face of the sophistication of modern cars where more electronic features can be tailored to the requirements of the individual. However to their credit BMW have bowed to public demand and effectively put in place a method of permanently disabling it called 'last use'.
    If Honda were to maintain this stances it would certainly deter me from buying one again, which is great shame because they make beautiful cars..
    I do hope Honda will sit up and take notice.