Do 335i owners keep the engine idling after a drive to cool?

[merlin5]

I heard from someone, that you are meant to leave the car idling for a while after a spirited run. Does anyone do this? If so for how long and what is the principle? Does it cool the turbos?

[Slippydiff]

Answered here : - (seventh question down) http://www.turbotechnics.com/docs/turbo/faq.htm

Edited by Slippydiff on Wednesday 13th February 00:29

[Robatr0n]

I don't know if it's the case with the 335i but generally speaking all turbo cars should be carefully warmed up and warmed down otherwise they have a habit of eating turbos.

I'm pretty sure that a 335i would have a recirculating oil function that cycles oil through the system until it cools down (my 91 audi does!) but I still let my old banger idle for a minute or so after a particularly hard run.

This probably isn't much help to you to be honest, but I do have a great deal of mechanical sympathy for cars.

[eowen]

Agree you should take care to not drive too hard until the car has warmed up. Regarding cooling down, our german friends have through of this and the cooling system/pumps continue after you stop the car, so there is no need to do this.

[dxb335d]

As the last two chaps said, oil is circulated after shutting down so there should not be an issue. What i want to know is whether that applies to the 335d also.

[MattOz]

You should always let the turbo(s) spool down after a spirited drive. People tend to forget this and rely on systems that claim to do the same thing. They do not.

The best way to cool things down is to run off boost for the last couple of miles of your journey before switching off.

Matt

[dxb335d]

How do you run ''off-boost'' on a 335d, where the turbos, well at least the diddy one will be spinning at the merest ''thought'' of throttle pressure.

[vincenz]

dxb335d said:

How do you run ''off-boost'' on a 335d, where the turbos, well at least the diddy one will be spinning at the merest ''thought'' of throttle pressure.

Just stack it into a ditch then you'll stop posting crap.

As for cooling it down, there are cooling systems in place. Its not like theyre renault 5's

[Broccers]

vincenz said:

Just stack it into a ditch then you'll stop posting crap.

As for cooling it down, there are cooling systems in place. Its not like theyre renault 5's

Bad day ?

[baz1985]

ffs, you spend nearly £30k+ and then you to f8ck about like that... Sod it, if it breaks, it breaks that's what the warranty is for.

[dxb335d]

vincenz said:

dxb335d said:

How do you run ''off-boost'' on a 335d, where the turbos, well at least the diddy one will be spinning at the merest ''thought'' of throttle pressure.

Just stack it into a ditch then you'll stop posting crap.

As for cooling it down, there are cooling systems in place. Its not like theyre renault 5's

What a lovely reply. Not nice wishing someone dead. Most people would read your reply and think your a wr.


I want to know how you drive a car which boosts very early on in the rev range and under light load ''off boost'' thats all.

[Robatr0n]

You are right Carl, its very hard to drive a car off boost when you have the small one spinning at such low revs. You can however lay off the accelerator and keep boost to a minimum.

As I say, most cars recirculate oil after you stop to cool things down slowly but I would always advise letting it idle after a hard run.

[vincenz]

dxb335d said:

vincenz said:

dxb335d said:

How do you run ''off-boost'' on a 335d, where the turbos, well at least the diddy one will be spinning at the merest ''thought'' of throttle pressure.

Just stack it into a ditch then you'll stop posting crap.

As for cooling it down, there are cooling systems in place. Its not like theyre renault 5's

What a lovely reply. Not nice wishing someone dead. Most people would read your reply and think your a wr.


I want to know how you drive a car which boosts very early on in the rev range and under light load ''off boost'' thats all.

I didnt say anything bout wishing you dead, just the BMW section seems to be littered with your posts bout your beloved 335d to the extenet where your views are just stupid.
The M3 v 335d is a good case in point.

Bottom line is they will never sound as good as a petrol.

[Methane Bloke]

It's a good idea to run the car on light throttle for the last few minutes before switching off, not to let the turbos spool down as this only takes seconds, but to allow heat to dissipate from the turbo housing. As has been posted most turbos now have cooling systems in place to help this situation. Also fully synthetic oils have helped lowered heat induced turbo failures.

On the subject of diesels, running a 335d on light throttle, whilst producing plenty of boost from the small turbo, is not producing anything like the exhaust gas temperature that occurs with WOT. In any case the exhaust gas temperature is a lot lower with a diesel engine than it is with a petrol.

Regards

Chris

[dxb335d]

vincenz said:

dxb335d said:

vincenz said:

dxb335d said:

How do you run ''off-boost'' on a 335d, where the turbos, well at least the diddy one will be spinning at the merest ''thought'' of throttle pressure.

Just stack it into a ditch then you'll stop posting crap.

As for cooling it down, there are cooling systems in place. Its not like theyre renault 5's

What a lovely reply. Not nice wishing someone dead. Most people would read your reply and think your a wr.


I want to know how you drive a car which boosts very early on in the rev range and under light load ''off boost'' thats all.

I didnt say anything bout wishing you dead, just the BMW section seems to be littered with your posts bout your beloved 335d to the extenet where your views are just stupid.
The M3 v 335d is a good case in point.

Bottom line is they will never sound as good as a petrol.

I didnt start the thread, and was merely pointing out my views and feelings on the matter. Did you see the video posted near the bottom by Sniff petrol?

[davidd]

The last bit of any journey for me is meandering through our village and then parking up. I have always felt that was always enough to ensure the engine had a stress free end of trip and could then be shut down.

D

[sniff petrol]

davidd said:

The last bit of any journey for me is meandering through our village and then parking up. I have always felt that was always enough to ensure the engine had a stress free end of trip and could then be shut down.

D

The only turbo cars I've owned have only been diesels and I figure that by the time you pull in and manouvre to park that things have cooled down enough to not suffer problems. You'd have to be driving flat out for mile after mile of motorway then do an emergancy stop on the hard shoulder and then switch the engine off immediatley to suffer failures from excess heat IMO.

[Boulder]

With my old 400bhp cosworth running 30psi,i always kept it below 3k rpm for 10 mins and after a hard run did the same prior to turning off.

What causes huge heat in turbos is sustained WOT,and if you switch off directly after this then an awful lot of stress is caused.The recirc feature is merely to aid lubrication to the shaft bearings upon shut down of the engine, it wont prevent damage caused by 'shock cooling' which is bad for any blower.

[Methane Bloke]

When I was rallycrossing many turbos suffered heat induced failures when cars crashed and the turbos were unable to be cooled down gradually after racing at full tilt.

Regards

Chris