Do turbos blow up if you don't let the engine idle before switching off?!!

[TeaMonsta]

Read somewhere on the internet last night that Nissan X-Trails suffer from their turbos blowing up. Apparently this happens (so the author says) if you don't let the engine idle for 30secs before switching it off. The turbo then gets starved of oil which leads to it blowing up (or at least malfunctioning in some way). I've been running a TDi Golf for a couple of years and never idled the engine before switching off. And I haven't done it with the Surf either (although I've only done 2000 miles in her). So it it complete and utter sh!te?

[Rob5464]

To my knowledge it will inevitably reduce the life of the turbo due to oil starvation. However Its not going to blow up. I don't know anyone who lets it idle for 30 seconds but revving it up and turning it off is not going to do it any good.

[wishbone]

I let the surf tickover for a bit if it's just pulled off the motorway or been up and down hills fully loaded. Normal driving about I don't bother. With the surf it's probably as much for the cooling system as it is the turbo though

[StevenN]

Your not wrong just a little misinformed.
Older turbo designs like the ones found on the Surf can be overworked and if not let to run down they can overheat and break.
You may have a after market gadget called a turbo timer fitted to your surf.
Mine has and its a little black box mounted to the side of the steering column.
Its job is to keep the engine running for a pre determined time after you switch off the ignition.
I believe the use is frowned upon in the UK and mine is unplugged.
If you put your turbo under a lot of prolonged strain it may be prudent to run the engine a little before you switch off.
Most people don't bother or need to.

If you search for turbo timers you will find more info

[red barron]

Turbos don't "blow up"! What can happen if you shut the engine down from high revs, especially when hot. The turbo is starved of oil as the pressure drops to zero because the oil pump stops with the engine. This can lead to the premature
failure of the turbocharger bearings resulting in turbo failure. Bear in mind the temperature of the turbo are typicaly between 500 and 800 degrees F. You can imagine the damage caused when the oil stops flowing and the turbo is spinning at speeds up to 150,000 rpm ! But there are other factors to bear in mind such as oil quality and of course regular servicing.

[markjd]

Your not wrong just a little misinformed.
Older turbo designs like the ones found on the Surf can be overworked and if not let to run down they can overheat and break.
You may have a after market gadget called a turbo timer fitted to your surf.
Mine has and its a little black box mounted to the side of the steering column.
Its job is to keep the engine running for a pre determined time after you switch off the ignition.
I believe the use is frowned upon in the UK and mine is unplugged.
If you put your turbo under a lot of prolonged strain it may be prudent to run the engine a little before you switch off.
Most people don't bother or need to.

If you search for turbo timers you will find more info

Never heard of the use of turbo timers being frowned upon. Must be why people don't like scooby drivers lol
I use mine all the time only 10 seconds just to let the speed come down on it.

[wishbone]

Pretty sure it's illegal to leave a car running on public roads with nobody in it.

[TeaMonsta]

Thanks alot for all your replies, guys. Much better informed now The Surf never gets driven hard. I'm always easy on her, generally limiting the revs to 2000 (as long as it doesn't compromise safety), but the info you've provided is useful to know.

[yorta2]

Quote from Surf Owner's Manual: Page 49, Engine Start/Stop:

"Should your engine be fitted with turbo capabilities and you have been driving fast (over 80km/hr), up/down hills or over sand hills etc., it is advised to let the engine cool down the turbos a little whilst in idling speed, before turning the engine off (around 1 minute)."

[tweak'e]

Read somewhere on the internet last night that Nissan X-Trails suffer from their turbos blowing up. Apparently this happens (so the author says) if you don't let the engine idle for 30secs before switching it off. The turbo then gets starved of oil which leads to it blowing up .....

what your referring to is not a turbo dieing from oil starvation but rather oil coking in the turbo and causing the bearings to fail.

the simple problem is that the turbo is very hot and is cooled by the oil. engine stops, the oil supply stops and the oil in the bearing gets heated by the heat soak. when its heated to hot it forms carbon. the carbon builds up and causes damage to bearings.

some turbo's have water cooling to combat the heat soak. so those turbo's with water cooling may not need much time to cool down before switching off the engine.

[tashtego]

Mine has the turbo timer. It's starting to get annoying when you park to go shopping and some guy runs after you to tell you you "have forgotten to turn engine off!". So now I switch engine off BEFORE pulling the handbrake and that does the trick. However I leave it to do its thing after longer trips.

[tweak'e]

cheaper way and safer way than using a turbo timer is to just use a temp gauge.
an egt gauge will give a fairly good indication of turbo temp.
or you can fit one of many high temp gauges around directly to one of the turbo bolts.

[markjd]

Pretty sure it's illegal to leave a car running on public roads with nobody in it.

With the keys in maybe. Not gonna get far in 10 seconds with steering lock on.

[shokenore]

Pretty sure it's illegal to leave a car running on public roads with nobody in it.

With the keys in maybe. Not gonna get far in 10 seconds with steering lock on.

Assuming the turbo timer is set for 10 seconds, which is unlikely, and if it was set at ten seconds that would be pretty pointless, turbo timers would probably be a good idea on a tuned motor pumping out plenty of HP and as which that engines oil would already be under more stress, on a surf pretty much something else to go wrong.

I think it would take me longer to pull up set the brake stash the sat nav unplug my Ipod grab my phone, take a swig of my coffee before I turned then engine off than a turbo timer set for ten seconds.

S42 of the RTA 1988 deals with leaving an engine running in a unattended vehicle.
There is also legislation dealing with idling engines.

[Karma Supra]

I actually forget my surf is turbo... it doesn't feel like one!

I used to have turbo timers on my supras that adjusted the idle time according to how hard you thrashed the car...

To be fair the surf doesn't get driven that quickly, and the minute or so it takes to turn around and park for me will be more than enough.

Diesel turbos also run much cooler... I've never had anthing in the surf engine bay glowing cherry red