TODAY's TURBO-Do You Idle Before Shutdown

[jason510]

There are going to be rare circumstances where 30-60 seconds of idling may help. But we're usually talking about high output, modded powertrains operating well outside factory parameters after a hot lap.

Unless specifically called out in the owner's manual, which is rare, there's honestly no need to to do it on stock configurations.

That's what I'm leaning toward.

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[sgtmorph]

The last post is correct, you do not need to post-idle your engine, and I am saying this as an engineer for a turbocharger company. On a water-cooled center-housing turbo (all modern gasoline turbos), the cooolant continues to circulate a bit even (thermo-siphoning) after the engine shuts down. Besides, idling is rough on an engine for a number of reasons, and while the oil temp will drop during idling, the underhood temps rise. The underhood temps can be an isssue for the longevity of all the rubber and plastic components in the engine compartment, as well as the battery. The best way to cool off the turbocharger after some really hard driving is to just drive easy at moderate speeds. This gets a good flow of fresh air flowing through the engine compartment. If you are at a competitive event, open the hood after your run.

Dave

As someone who has done track events, this is All truth!

 

[WoolyKris]

Agree with majority here, for normal driving if you idle you just wasting your gas.

 

[Dan9908]

This issue was definitely something that was advised back in the late 80’s when turbos were eeking their way into the consumer market. I vividly recall going from dealer to dealer looking at cars with my parents... they were interested in a Saab, Benz and (oddly enough) a Turbo-T. Every dealer mentioned the added insurance premiums with the “turbo” designation as well as the cool-down idle step.

My mom picked up an 87 Accord LX-i and I recall the test ride in the Regal, which was my default choice

 

[Cornercarver]

I've been reading up on this topic and there doesn't seem to be a consensus. That is letting your engine idle for a minute or two to help cool the oil in the turbo before shutting down.

I know that turbos have evolved from the early days, but there doesn't seem to be a consensus on TODAY's TURBO's. One part of me says to treat my car well with scheduled maintenance and not over think it, while the other knows I plan on having this car for a while and we know about an ounce of prevention.

What are your thoughts and practices?

I realize that modern turbos are cooled differently, etc. but I like to idle a bit - like a minute - after hard driving for a long time. Probably I err on the side of being overprotective. Good to know that the engine design now acts a little bit like the turbo timers of the past supplying cooling while the turbo spools down.

 

[Neps18Si]

Think of all the cute chicks driving the hatchbacks...(my wife may be one of them). Ask them if they know about idling before shutting off the car. Hell nah. Maybe a fraction of them. Even though I idle the car and even do some light driving before pulling up my driveway I tend to let the turbo spool down and cool off. Even though we don't have to. Just a piece of mind for us car geeks here.

 

[jason510]

Think of all the cute chicks driving the hatchbacks...(my wife may be one of them). Ask them if they know about idling before shutting off the car. Hell nah. Maybe a fraction of them. Even though I idle the car and even do some light driving before pulling up my driveway I tend to let the turbo spool down and cool off. Even though we don't have to. Just a piece of mind for us car geeks here.

I'm thinking those hot chick's don't give a crap about the engine, but point well taken.

 

[Slap KFD]

Just remember, it's not 40 years ago anymore. We don't adjust carbonators on new cars either.

 

[Slap KFD]

K

 

[SuperMotoManDRZ]

The last post is correct, you do not need to post-idle your engine, and I am saying this as an engineer for a turbocharger company. On a water-cooled center-housing turbo (all modern gasoline turbos), the cooolant continues to circulate a bit even (thermo-siphoning) after the engine shuts down. Besides, idling is rough on an engine for a number of reasons, and while the oil temp will drop during idling, the underhood temps rise. The underhood temps can be an isssue for the longevity of all the rubber and plastic components in the engine compartment, as well as the battery. The best way to cool off the turbocharger after some really hard driving is to just drive easy at moderate speeds. This gets a good flow of fresh air flowing through the engine compartment. If you are at a competitive event, open the hood after your run.

Dave

My IAT's and overall engine compartment temps always rise at idle.. when I get back home after a spirited drive my intake/intercooler components are always cool enough to touch.. it's when I let it idle is when things heat up.. what I do after driving the car hard is park in my driveway, pop the hood, and let it idle for a bit. The heat escapes and it cools down more efficiently. It's not really needed, but it gives me peace of mind. Sometimes I just turn it off and pop the hood if I haven't been driving it hard. Just little things to let it cool down naturally.

 

[Purple Drink]

Sorry, but there is some really bad info in this thread. Unless you are driving your car really hard right before parking it, just shut it off. Ever since the advent of water cooled turbos, you no longer need to idle before shutting down. Wonder why you rarely see people w/ turbo timers?... water cooled turbos are why.

This is absolutely correct. And on top of the mentioned if you have a R you can hear an aux pump run to help with the cool down after shut down.

 

[gtman]

Just remember, it's not 40 years ago anymore. We don't adjust carbonators on new cars...

Interesting. I've been driving for 40+ years and never saw one of these under my hood:

Perhaps you meant carburetor.

 

[jason510]

I saw this thread pop and started at the beginning. After reading the first post I thought to myself that this guy needs to chill and not overthink things.

Then I realized I was the one who started the thread.

 

[alxgravel]

Well before go home ... the last 1-2 min trying to babying the car before shut down. Get normal temp and oil circulation .

 

[Ap1 George]

I just make sure I don't do any hard pulls few minutes before I'm about to get to my destination.

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