Turbo Engine - Please Educate Me How to Drive & Care

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Sep 27, 2020
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Location
Vancouver, WA
Purchased a 2019 Mazda CX-5 with 2.5L Turbo engine, my first vehicle with Turbo engine, need some help from experienced folks.
I've read "not to drive until the engine has warmed up", "don't shut-off the engine right away", need some clarification on these two more than anything else.

Just a few minutes ago, the car starts right up idling at around 1,450 RPM, goes down to 1,200 after 30 seconds, took full 1 minute to reach 1,000. After 3 minutes it's hair below 1,000 RPM. The ambient temperature was 42℉. I usually drive off after 30 seconds of idling, but the OM says, "After starting the engine, let it idle for about 10 seconds". I then drive 25MPH for 3-4 min to reach 45MPN zone street.

The OM also says, "After driving at freeway speeds or up a long hill, trailer towing for a long time, idle the engine at least 30 seconds before stopping it. Otherwise, the turbocharger could be damaged". I have to drive 25mph before reach my driveway, do I still need to idle 30 seconds before turning off the engine?

Please feel free to give any and all advices so I can get clear idea , as I'm hoping to keep this CX-5 for 15 years/150,000 miles or longer.
 
!. Drive normally after about 15 seconds and after you hook up your seat belt.
2. Don't Accelerate fast or at wide open throttle until the engine is fully warmed up.
3. If I'm coming off the interstate after divining at 75 MPH for more than a half hour or so, I just drive slower for a mile or so to let things cool down

Modern turbo enginess are much more robust that 15 years ago. Modern turbos are oil and water cooled so no special treatment is needed. Read the manual, and you will find little or no special effort is needed. Ed
 
I bought an '86 Volvo 740 Turbo new. It was only oil cooled (not water cooled like the '87s) and I worried about it a lot. But it was still fine after 18 1/2 years and 285,000 Km.

When you have a very cold start, don't romp on the throttle. Take it easy getting started. My rule was no vigorous acceleration until the temp gauge was at least off the pin, and even then I took it easy until it was really warmed up.

When you drive at high speed on the highway you may find your turbo is red hot (a good shade of orange anyway). So you want to let it cool down a bit before you shut it off. I used to pull off into a service station and let it idle for a couple of minutes.

When I was coming home there was a block or so of low speed this way and that way driving before I actually got there. I took it easy for that last bit and just shut it off when I got to the house.

And I changed the oil a lot, every 3 months to be exact. Keep in mind this was in the days before today's much better oils.

Other than that just enjoy it.
 
Just take it easy before you shut it off. I go slow up my street and take it easy in parking lots when I go somewhere and that's enough. Ran my '92 MB 300Dm2.5 Turbo to 348k miles on the original oil cooled turbo without a leak, rebuild, or replacement.
If you've been cruising down the highway, well then give a cooldown. But again, the side streets once off the highway doing 20 to 35 miles per hour for a couple of minutes will do it. For anecdotal data point, go back to where I said "Ran my '92...."
The first turbo diesel I ever drove was a Deuce and a Half. They taught us to let them idle a minute or two before shutting down. New cars aren't old abused mil trucks.
Just common sense rules. If you've driven light on the home streets, no problem. If you just worked it hard, let it cool a minute.
 
Start engine. Put seatbelt, turn audio, etc. Hit the road.
Drive moderately, allow transmission to shift between 2,000-2,500rpms. This is how all cars should be driven cold, not just turbo.
Remember, oil temperature is what matters not coolant temperature. If you only have coolant temperature gauge, take into consideration that oil warms up much slower than coolant.
Shutting off engine: just drive moderately last mile, that is it.
 
Driving boosted car means you either don boost or off boost.
<25% throttle and you'll be off boost for the main part and your fuel consumption will reflect it.
 
Purchased a 2019 Mazda CX-5 with 2.5L Turbo engine, my first vehicle with Turbo engine, need some help from experienced folks.
I've read "not to drive until the engine has warmed up", "don't shut-off the engine right away", need some clarification on these two more than anything else.

Just a few minutes ago, the car starts right up idling at around 1,450 RPM, goes down to 1,200 after 30 seconds, took full 1 minute to reach 1,000. After 3 minutes it's hair below 1,000 RPM. The ambient temperature was 42℉. I usually drive off after 30 seconds of idling, but the OM says, "After starting the engine, let it idle for about 10 seconds". I then drive 25MPH for 3-4 min to reach 45MPN zone street.

The OM also says, "After driving at freeway speeds or up a long hill, trailer towing for a long time, idle the engine at least 30 seconds before stopping it. Otherwise, the turbocharger could be damaged". I have to drive 25mph before reach my driveway, do I still need to idle 30 seconds before turning off the engine?

Please feel free to give any and all advices so I can get clear idea , as I'm hoping to keep this CX-5 for 15 years/150,000 miles or longer.
Back in the day, with conventional oil, oil coking in the thrust bearing is more common, which is why you idled the engine before shut-off, and why turbo timers became popular.

WHen you drive 25 mph to reach your driveway, assuming that it's a flat road, it's probably not under boost, so that's fine.

WHen you turn on the car, let the engine come up to temperature before you go into max boost. Small turbos get into boost a lot quicker than large turbos... it's inertia, so even at 25 mph, you may be on boost to get to 25 mph, albeit maybe 1-2 psi, especially if you need to go up a hill.

Synthetic oils and water cooling virtually eliminates the need to let the engine idle for an extended amount of time before shutoff.
 

9 and 3 with thumbs placed along the rim up is the correct way because of the airbag.

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Your owners manual said exactly what I would say.

I have six turbo cars at the moment. All running their original turbos.

You should listen to Mazda on this one.

I will clarify that since you drive gently down the street, you don’t need to idle it in your driveway when you get home (or to work). My lovely bride doesn’t really read owners manuals. She starts up, backs out, then drives gently until the engine is warmed up. No excessive idling. When she gets home, her turbo car is driven gently down the street, and shut off when she parks in the driveway.

It has about 280,000 miles on it. Original turbo.

Use a good oil. Follow what Mazda said - 10 seconds is plenty of idling before driving gently off. Idling for a bit before shutting off won‘t hurt, but it doesn’t need to be long unless you’ve really had the turbo cranked up as your manual describes.
 
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I also have a 2019 Mazda CX 5 with the 2.5L turbo. From a cold start the revs drop fairly quickly down to about 1000 RPM's. I warm it up for maybe 30 seconds before starting out. I live about a mile from the highway so I drive it like a grandma until I get to the highway and then drive normally but not redlining the car. When coming home, most of the trip off the highway is downhill so I just coast until I get home. That is plenty of time for the turbo to cool down.

I think other important factors and to use only top tier gas, add a bottle of Techron before each oil change, use a really good oil like Mobil 1 EP and change it every 5000 miles even if the manual suggests 7500 miles. And keep a close eye on the coolant level. There have been some reports of vehicles made in that time period of leaks and resultant engine damage. Hopefully you have some kind of warranty.
 
Noting different. Turbo will probably not engage until engine temp is sufficient. That's the way subaru is. Also with subaru you have a turbo gage that constantly shows amount of boost. That's nice bc you can stay out of turbo 90+% of the time for better mileage.
 
Noting different. Turbo will probably not engage until engine temp is sufficient. That's the way subaru is. Also with subaru you have a turbo gage that constantly shows amount of boost. That's nice bc you can stay out of turbo 90+% of the time for better mileage.
“Not engage”??

They‘re not clutched.

Turbochargers spin when exhaust gas is present, the more exhaust, the faster they spin. Boost is controlled by bleeding off some of the exhaust gas via a waste gate.

But they spin 100% of the time, there isn’t any time that they are “not engaged”. They start spinning after the first cylinder exhaust valve opens on engine start.

So, making sure there is oil flowing to it before going above idle is key, as the turbo RPM climbs when more exhaust is flowing.

Good oil flow is key to turbo life. Avoiding a hot shutdown avoids coking the oil passages in the center section of the turbo, which preserves good oil flow for long life.
 
I drive 8 and 4. Or just 8. Or 6 with my knee 😎

I have noticed my water pump (electric) running for up to 10 minutes after long, fast freeway runs. I think being mindful of what the turbos are doing in extreme hot and cold, and being good at maintenance will keep them strong. 237k on mine but I doubt they’re original due to a wastegate rattle issue with the first design.
 
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