mrs daves new car has start stop but it also has a turbo. but you shouldn't switch off a turbo engine straight away but car will do it on its own :spin:
Stop start and turbos
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Stop start and turbos
There's a good chance the turbo is watercooled but even if it isn't the tolerances in them are much better and they are better built than 80s and 90s turbos. However if you want to allow it idle you can, just don't fill the pre-conditions for the stop start. So if you've been on the motorway don't lift the clutch in neutral until the engine has idled for a while. If its an auto switch the stop start off out of town.
We've had turbo stop start and you can manage when it stops the engine.
We've had turbo stop start and you can manage when it stops the engine.
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i keep forgetting to switch it off, but i have noticed sometimes it dont kick it in though and stays on so could it be clever enough to disable its self when it should keep ticking over?
The PSA THP engines have a seperate cooling system for the turbo which runs independent of the engine. Uses an electric coolant pump to cool the turbo even if the engine is switched off at the key.
There are something like 25-30 pre-conditions for stop start on the Citroen to work so turbo temp could well be one of them tbf.
There are something like 25-30 pre-conditions for stop start on the Citroen to work so turbo temp could well be one of them tbf.
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The Fiesta also has turbo and stop/start, and supposedly a supplementary electric water pump.
Had a pupil a year ago lived along a fast minor road. Used to pop up the long hill at 60, brake firmly, into their drive and along to the house. Then the stop/start would operate immediately. Moments later, boiling coolant would be gurgling into the header tank from the turbo. No sign or sound of any electric pump. Can't be good for the turbo. Wouldn't want a 3 year old used one.
Had a pupil a year ago lived along a fast minor road. Used to pop up the long hill at 60, brake firmly, into their drive and along to the house. Then the stop/start would operate immediately. Moments later, boiling coolant would be gurgling into the header tank from the turbo. No sign or sound of any electric pump. Can't be good for the turbo. Wouldn't want a 3 year old used one.
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ah this nissan might have some of them then would explain why it dint stop and start on the way home after i got it or when mrs dave took it out today.
There are all sorts, so for example on the way home if it's been on a forecourt a while the battery would have been low, so it would not have stopped until the battery was acceptably conditioned. Then theres coolant temp, it won't stop if the engines cold. Then theres current power draw, if it can't support what you are doing with out support from the alternator it's not going to cut the engine. They seem sensible enough..they start to get more and more obscure regards things like climate control settings and if it needs heat/to use the aircon to maintain current temperatures. For something that is in concept simple it gets pretty complicated.
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sounds like a big heap of stuff that could all go wrong one day. 
it wasn't from a forecourt it was a SureCheck Gold, grade 1 auction car.
it wasn't from a forecourt it was a SureCheck Gold, grade 1 auction car.
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On our new Giulietta 1.4 Turbo, we just switched the start/stop function off, small button on the dash...easy.
Don't like this engine behavior at all.
Don't like this engine behavior at all.
sounds like a big heap of stuff that could all go wrong one day.
it wasn't from a forecourt it was a SureCheck Gold, grade 1 auction car.
Most of it is stuff a modern car would monitor anyway, it uses data the car would already collect for a different purpose. E.g. it already monitors battery condition and power draw as modern cars shut off their alternator when the battery is full to reduce ancillary drag and save fuel. Same with coolant temp, crank position (it tries to stop the crank in the perfect position for easier restart) cabin temp e.t.c. e.t.c. I guess their may be additional wear on the starter but otherwise switching it off changes nothing. All the sensors are still present and still do their day jobs..it'll just be some more code in the ecu using information the car uses in it's day to day running regardless of the system being active.
I.e. its a modern car even without stop start it's still really complicated.
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this one seems to reset to on every time i turn ignition off and on again.
how does that work alternator is still going around if its switched off
how does that work alternator is still going around if its switched off
The mechanical drag would remain the same however the main component of the drag of the alternator is load is electro magnetic drag which is linked to the load the alternator is under. The car recognises when charging is not required and stops charging allowing the alternator to spin more freely.
Most stop/start cars will not stop the engine if you've just reversed. After a reverse, the likelihood of needing to go forwards again is high, so no engine stop.
My Alfa has only activated S/S once (I've not switched it off), and I've been in plenty of situations where it *should* activate. Suspect Alfa-itis.
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I tried it once, when the car was brandnew, it worked, but after that, I switched it of, permanently
I did almost 100k in a twin air with stop start.
Never a turbo problem, although I rarely arrived at junctions with the turbo spinning furiously either.
D
Never a turbo problem, although I rarely arrived at junctions with the turbo spinning furiously either.
D
this one seems to reset to on every time i turn ignition off and on again.
how does that work alternator is still going around if its switched off
Same with out min and golf the S/S always turns back on each time you restart the car.
With the newer more advanced cars, if the battery is full then they have more complicated systems for charging the battery.
My golf has regenerative braking so in normal driving the battery isn’t charging and when you brake the battery is charged at high current to provide additional engine braking, without the brakes coming in unless your breaking harder than the force exerted by the regenerative breaking. This makes the car much more efficient as slowing down forces are used to charge systems quickly, allowing less work from the engine when in normal driving.
I have a horrible habit of riding the clutch when sat stationary in traffic often forgetting to use the stop start, S/S does take some getting used to.
40k on the golf now, 60k on our last mini and about 10k on the new mini and no problems at all with the stop start systems on those cars or the batteries and no problems with the turbochargers.
As stated there are lots of conditions that state when the system will work or not, my golf won’t let S/S work Immediately after motorway driving, to let everything calm down.
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I must say, after living with one for about 18 months now, I really don't like it either. They say that the starter motors are beefed up to take the extra duty but I think they will still fail early especially on the a city driven car. I have read that combined starter/generators which are permanently engaged with the engine are the coming thing but as long as we have a starter which throws a gear into the flywheel ring gear I'm going to keep pushing the cancel button every time I start my engine.
My engine also has an electric pump in addition to the mechanically driven water pump which is mounted on the back end of the head and driven by a small synchronous belt all of it's own! (Both pumps, including their casings, are now completely made of plastic!). I have been in the habit of letting the engine idle for a minute or two if I've been driving hard before switching off (years of owning turbo diesels) I must have a listen to see if the electric pump runs after switch off as I've not noticed any signs of "water gurgle" on a hot switch off.
A couple of other modern inovations I don't like are hill hold and having to depress the clutch to operate the starter. I know the clutch thing is to stop any chance of the car jumping forward in case it was left in gear but I wonder about what provision has been made for crankshaft thrust washer lubrication for those first few revs 'till oil pressure builds up? Especially if the car hasn't been started for a few days, as mine often is now that I'm retired. The hill hold I don't like because I find it "holds" for too long and I end up slipping the clutch for measurably longer than when hill hold is not active.
My engine also has an electric pump in addition to the mechanically driven water pump which is mounted on the back end of the head and driven by a small synchronous belt all of it's own! (Both pumps, including their casings, are now completely made of plastic!). I have been in the habit of letting the engine idle for a minute or two if I've been driving hard before switching off (years of owning turbo diesels) I must have a listen to see if the electric pump runs after switch off as I've not noticed any signs of "water gurgle" on a hot switch off.
A couple of other modern inovations I don't like are hill hold and having to depress the clutch to operate the starter. I know the clutch thing is to stop any chance of the car jumping forward in case it was left in gear but I wonder about what provision has been made for crankshaft thrust washer lubrication for those first few revs 'till oil pressure builds up? Especially if the car hasn't been started for a few days, as mine often is now that I'm retired. The hill hold I don't like because I find it "holds" for too long and I end up slipping the clutch for measurably longer than when hill hold is not active.
Going back to the qashqai i'd be more concerned about watching engine oil levels in the 1st few weeks rather than what the stop start is up to. From what I've read some Renault Tce units (so qashqai and kadjar e.t.c.) left the factory with slightly small pistons resulting in lots of oil use and eventually new engines.
Hopefully won't affect you but keep an eye as some people have missed the oil use and only realised when the oil pick up for the timing chain could no longer get any resulting in timing chain death rattle.
Hopefully won't affect you but keep an eye as some people have missed the oil use and only realised when the oil pick up for the timing chain could no longer get any resulting in timing chain death rattle.
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i've heard the 2.0 were bad but 1.6 supposed to be ok? i didn't do enough research so didn't know they had a French engine until it was too late
