lexusplz

I was thinking of getting the 2015 IS 250. I test drove the IS 250 2015 yesterday and I wasn't really too impress with the performance on the freeway. I do like the interior, and the overall comfort ride. Now, I think I'm going lean towards the IS 200t after reading a lot of positive responses to the NX200t. This is going to be my first turbo engine car. My questions are:

1) Reading the NX200t forum, I read someone say you need to leave the car idle for about 3mins before shutting off the car? Is that how it works for Turbo engine?

2) What kind of maintenance are needed on a Turbo engine?

brendanf

You should check with Lexus about the 3mins. I can say most people recommend it to give the turbo time to cool down by pumping engine oil through it. It is believed that if you just shut off the engine the heat from the bearings in the turbo will cook the oil and you'll get build up on them that will affect the ability of the turbo to spool. Turbo technology has changed a lot in the last 10 years so I highly doubt the 3 min requirement is even of use these days. Most turbos have actual bearings in them instead of a bushing like they used to so it is a non-issue.


Turbo engines need regular oil changes with proper oil. No cheating here. You also will need to use premium fuel.

PAPI007

Wow, I never knew this! that seems like to much work. Lol- I will stick with my IS350.

brendanf

It's one of the reasons I grabbed a 2015 instead of waiting for the 16. My plan is always to get 10yrs out of a car and that can be hard with a turbo. They wear out and sometimes it doesn't matter how good you are with it they crap out, or the seals can leak oil and suddenly your smoking a bit or have higher oil consumption. And to replace one is not cheap.

I am not sure how well Lexus/Toyota have developed their own turbo tech, I know the Supra is a great example but that was a long time ago and to be honest they never sold that many of them either to be a good base line. If it was a VW then yeah I would trust it to go forever..

PKSkull77

Though admittedly I've never owned a Toyota turbo car, I've owned several STi and an Evo as well. Letting those car cool down for 3 minutes before shutting them off was not necessary and I'd be shocked if it was needed with the NX200t. You hear these sorts of comments from people who are misinformed or paranoid.

Owning a turbo engine is a lot like owning a naturally aspirated car. If you drive the car like a normal human being you won't have any issues. If you drive the car like a clown, you should use better oil, and change it at regular intervals.

The bottom line is that if it's getting a Lexus badge, it's probably going to be very reliable. As long as your not modifying it, you can get the car fixed for free if anything goes wrong.

If you plan on modifying the car, you always run the risk of reducing reliability turbo or not. With that being said, coaxing more power out of a turbo charged engine is a lot easier than one that is naturally aspirated.

corradoMR2

Besides some lag on take off, the NX is faster than the IS 250 despite the 400 lbs heavier weight. You'll love the 2L Turbo from a power and fuel economy standpoint, but sound is far sportier from the 250's V6 if you care for that.

1. Based on the manual, yes 3 mins for heavy driving but 20 seconds in normal city driving. During the latter which is our most common use for the NX, I let it idle about 10 seconds and a little more for short highway trips.

2. Nothing more than would be done on a normally aspirated Lexus engine with the exception of oil top ups as needed. Oil changes are every 10k miles with top ups at every 5k miles. My NX had some oil added at 5k miles.

lexusplz

Thanks for the explanation and picture.

When you say sportier sound, are you saying the turbo engine will louder than a v6?

" Oil changes are every 10k miles with top ups at every 5k miles."

- I'm not clear when you mention 2 numbers here. So is it every 10k you change oil for the Lexus or 5k?

Wow...there's a lot of cautious things to be aware of when driving a turbo. "Do not driving continuously in lower gear? wut".

-This is referring to a manual transmission right? Correct if I'm wrong, when you start off accelerating, don't you start with first gear which is lowest gear? So you can't drive slow all the time in the city?

"Do not drive at a constant speed for an extended period of time?"

-So I shouldn't turn on cruise control...? I can't drive constant at 65 MPH - 70 MPH for optimal fuel efficiency on the freeway?

3ISRC

I say just drive it and take care of it just like a N/A. If you find the need to wait 3 min. before shutting off the car then find an aftermarket turbo timer for convenience. Just follow the maintenance schedule and you will be fine. I had a modded Evo prior to my IS and it was reliable up to 180k miles when I sold it. No major issues with occasional hard driving. Most guys either blow their motors, replacing their transfer case, or replacing their clutch frequently on an Evo all because of how they drive their cars. This apply on NA as well modded or not. It really comes down to how you drive your car and how you maintain it.

How big is the turbo on the IS200t and stock boost? I can't imagine it being a a good size turbo and running at high psi stock like other turbo cars out there that are race inspired.

My0gr81

The turbo will have more noise as it kicks in and "twin scroll" design means it is running even when it doesn't kick in, so the sound of the turbo will be there. Not a bad sound at all, blends in very well with the engine / exhaust sound. I would say on par with the 2.5l V6 DI engine.

Oil "CHANGE" @ 10K miles, Oil "TOP UP" at 5K miles

As per the screen print from the manual, this part is only for the break in period in the first 1000 miles.

corradoMR2

You sound concerned. Don't be. Reminder, I have both the IS 250 and the new 2L Turbo in the NX and I drive and operate the NX the same way I do the IS. The only thing "special" is idling it for a few seconds after normal use before shutting down the engine, that's all you need to do differently as an owner. All the rest, regular scheduled maintenance will take care of your trouble-free driving for years.

Regular maintenance is every 5k miles where they top up all fluids (oil, windshield fluid, brake fluid, etc as needed) with full oil changes (oil drained, filter replaced, new oil added) done every 10k miles. This 5k and 10k servicing is typical of late model normally aspirated Lexus/Toyota engines in the US, i.e. such as on the IS 250.

As My0gr81 stated, the above speed and driving constraints are during the break in period. After that drive it like you normally would. Note, no manual transmission available on any of the 3rd gen IS engines nor with the upcoming 2L Turbo 4 cyl. They're just referring to automatic transmissions you can switch to manually select your own gears when in "M- Mode" (or "manual" mode). If you're unfamiliar with this, simply put the car in "D" and drive!

For the sportier sound, to be clear, I'm referring to the 250's V6 engine. The 2L Turbo 4 cyl's sound is not as sexy which is typical for the majority of inline 4 cyl engines versus the deeper bass and growl you get from a V6. I took both on the track a couple months ago to give you an idea:



If your priority remains highway passing power, the 2L Turbo is a gem. Where the 250's V6 runs out of steam the more you press the accelerator, the NX's Turbo does the opposite. It gives more when you press more. You feel a lot more in control and safe you will make the pass.


Exactly, it's not running at very high PSI. Under normal driving, you may hit 3-5 psi under moderate acceleration in pace with traffic, while hwy cruising you're constantly hovering around 1-2 psi, but of course it can max out at a pretty generous 17 psi under full throttle.

SummerRain

One more minor thing. The cabin engine sound in NX200t is generated artificially and broadcast through the speaker, you can turn that feature off. The cabin engine sound in IS250 is generated by the resonator at the intake. In short, the sound in NX200t is "fake" and the sound in IS250 is "real"

JDR76

^^ If I recall correctly, CorradoMR2's NX does not have the sound generating feature. Differences with the Canadian spec models... In the US, I think the engine sound is only on the F Sports (I could be wrong).

corradoMR2

Correct, for US models, you have the ASC (Active Sound Control) switch on NX F Sport's that can enhance artificial sound in the cabin.

What you hear in the video with the NX is natural since we don't get ASC in Canada, as JDR76 mentioned.

SummerRain

Thanks for pointing that out. IS250 does sound a lot better in my own opinion. I believe my 350 will be even better