2016 IS200T is on US EPA gas mileage website now

IS-SV

Premium Member
Messages
1,886
Reactions
1,350
I'm with you corradoMR2 ... there is too much idle vibration in our 200t NX especially when using the brake-hold feature. Vibration is why I've usually steered clear of a 4 cylinder. On a recent Lexus Advisory Board survey, when questioned extensively about satisfaction with 2.0L turbo4, I have offered strong objection to the lack of a NX V6 option.

These are good observations that you and cMR2 have made regarding the Lexus 2.0L turbo, especially since the 2 of you put in plenty of driving seat time. It's also disappointing to hear of the vibration.

In contrast I've driven both Mercedes turbo 4's extensively (1.8L turbo and 2.0L turbo) back to back with the best Lexus V6 (3.5L used in the IS, RC and GS) and have found the difference in NVH to be insignificant and both 4's worthy of inclusion in top tier premium cars. Both Benz turbo4's are smooth and quiet at idle, quiet and smooth to 6000 rpm. Even though the Benz turbo's are small displacement (2.0L and under), they use all the latest vibration suppression techniques including balance shafts which are typically not employed with 4's this small by many automakers.

I've also driven too many IS250 loaner cars extensively, and I can say I won't miss them.

Sounds like Lexus has some work to do. IMO they need to improve the turbo4's to stay competitive, especially for base engine applications. Of course continuing to offer a V6 upgrade at extra cost is also good for profitability.
 
Last edited:

corradoMR2

Founding Member
Messages
729
Reactions
1,124
I'm with you corradoMR2 ... there is too much idle vibration in our 200t NX especially when using the brake-hold feature. Vibration is why I've usually steered clear of a 4 cylinder. On a recent Lexus Advisory Board survey, when questioned extensively about satisfaction with 2.0L turbo4, I have offered strong objection to the lack of a NX V6 option.

I'm also with corradoMR2....and, of course, with you. :) Not there's anything really wrong with the turbo 4, especially if you like the power, but I agree the V6 is more refined overall to drive. Given the choice, I'd take a little less HP/torque (if applicable) and a little more refinement.


I have a poll running at CL on the vibration issue and a significant 40% of owners feel the same 760 rpm (to be precise) vibration in the seat of their pants. :confused: I brought it in for servicing and they found nothing wrong. On the flipside, the fact that 60% of owners do not have this issue indicates the vibrations is not by design. I also brought it to Lexus Customer Service's attention to no avail.

I have found that a hot engine (i.e. stuck in traffic for a significant time) exacerbates the issue at times, but we (owners) haven't found any solid correlation (yet) to fuel octane, fuel brand (and detergents), HVAC on or off, and environmentals. My latest: I'm testing a full tank 91 Octane Esso fuel and about 100 kms in, so far no abnormal vibration... Coincidence? Not sure yet and still a little early to tell...
 

RAL

Moderator
Messages
1,224
Reactions
1,772
I have a poll running at CL on the vibration issue and a significant 40% of owners feel the same 760 rpm (to be precise) vibration in the seat of their pants. :confused: I brought it in for servicing and they found nothing wrong. On the flipside, the fact that 60% of owners do not have this issue indicates the vibrations is not by design. I also brought it to Lexus Customer Service's attention to no avail.

I have found that a hot engine (i.e. stuck in traffic for a significant time) exacerbates the issue at times, but we (owners) haven't found any solid correlation (yet) to fuel octane, fuel brand (and detergents), HVAC on or off, and environmentals. My latest: I'm testing a full tank 91 Octane Esso fuel and about 100 kms in, so far no abnormal vibration... Coincidence? Not sure yet and still a little early to tell...

After driving almost 15k, I have noticed the vibration growing worse to the point of irritation, especially when I use the auto-brake feature (which is not often since I rarely drive in the city). The only recent change I am aware of is the onset of much colder weather here.
 

mmcartalk

Expert
Messages
4,159
Reactions
2,675
I have a poll running at CL on the vibration issue and a significant 40% of owners feel the same 760 rpm (to be precise) vibration in the seat of their pants. :confused: I brought it in for servicing and they found nothing wrong. On the flipside, the fact that 60% of owners do not have this issue indicates the vibrations is not by design. I also brought it to Lexus Customer Service's attention to no avail.

Is this poll for all Lexus 2.0T owners, or just 2.0Ts in one specific Lexus vehicle? I ask because several different design factors can affect low-RPM vibration, even with the same engine, in different vehicles.....among other things, design of motor mounts, design of the steering column where you feel it through the wheel, HP/torque programming where the computer regulates fuel mixture and spark timing, and the A/C compressor. A fully-warm engine will usually tend to have a lower idle speed than when cold or during early warm-up, exacerbating any vibration-issues.
 
Last edited:

mmcartalk

Expert
Messages
4,159
Reactions
2,675
After driving almost 15k, I have noticed the vibration growing worse to the point of irritation, especially when I use the auto-brake feature (which is not often since I rarely drive in the city). The only recent change I am aware of is the onset of much colder weather here.

The colder weather you mention could be a factor, because it would tend to thicken up the fluid some that is inside the motor mounts of many of today's upmarket vehicles. The cold, thicker motor-mount fluid would naturally transmit more vibration than thinner fluid when the engine has warmed up. But, as I replied to corrado, that effect, to some extent, would be counteracted by a lower idle speed and more idle-vibration as the engine warms...so, it may be just a question of what is more effective at what engine-temperatures.
 
  • Like
Reactions: RAL

corradoMR2

Founding Member
Messages
729
Reactions
1,124
Is this poll for all Lexus 2.0T owners, or just 2.0Ts in one specific Lexus vehicle? I ask because several different design factors can affect low-RPM vibration, even with the same engine, in different vehicles.....among other things, design of motor mounts, design of the steering column where you feel it through the wheel, HP/torque programming where the computer regulates fuel mixture and spark timing, and the A/C compressor. A fully-warm engine will usually tend to have a lower idle speed than when cold or during early warm-up, exacerbating any vibration-issues.

Mike, it's for the NX here
Also have one for the IS here. I was hoping the IS would be smoother considering the engine is mounted longitudinally, but similar sentiments though the sampling is still too low in that poll at this time.
 

mmcartalk

Expert
Messages
4,159
Reactions
2,675
Mike, it's for the NX here
Also have one for the IS here. I was hoping the IS would be smoother considering the engine is mounted longitudinally, but similar sentiments though the sampling is still too low in that poll at this time.

Thanks for reminding me about that. :) Among the different vehicle factors affecting engine-vibration, I had forgotten about that one........longitudinal vs. transverse mounting. Both, of course, usually require different motor-mounts at different attach-points in the block and/or sub-cradle.
 

IS-SV

Premium Member
Messages
1,886
Reactions
1,350
RAL/cMR2 - I hope a software fix might help with a more (consistently) smooth idle...

How about the rest of the Lexus 2.0L turbo's powerband NVH, including mid-range and all the way to redline. What's your observation regarding smoothness and sound quality in the important 2000-6500 rpm range. Because expectations for a true premium car are that the engine should sound expensive and rev smoothly even when pressed in the upper rev ranges. (Unlike most mainstream 4 bangers which sound econo box crappy when revved above 4500).
 

corradoMR2

Founding Member
Messages
729
Reactions
1,124
RAL/cMR2 - I hope a software fix might help with a more (consistently) smooth idle...

How about the rest of the Lexus 2.0L turbo's powerband NVH, including mid-range and all the way to redline. What's your observation regarding smoothness and sound quality in the important 2000-6500 rpm range. Because expectations for a true premium car are that the engine should sound expensive and rev smoothly even when pressed in the upper rev ranges. (Unlike most mainstream 4 bangers which sound econo box crappy when revved above 4500).

I thought the 2L Turbo in the NX was pretty good in the NVH department to redline until I had a Ford Fusion 2L Ecoboost rental for a business trip a couple months back. Shockingly, the Ford's powertrain was more quiet, smooth revving, and vibration-free below about 4500 rpm which is the powerband people will use 99% of the time. But above that, it had more NVH than the Lexus 2L. Overall, I was left impressed with the Ford and somewhat disappointed with the NX's 2L and noticed how it was a little louder when I drove the NX immediately after the Fusion. I haven't tried this engine on the IS and wonder if it's any different in the NVH department.
 

IS-SV

Premium Member
Messages
1,886
Reactions
1,350
I thought the 2L Turbo in the NX was pretty good in the NVH department to redline until I had a Ford Fusion 2L Ecoboost rental for a business trip a couple months back. Shockingly, the Ford's powertrain was more quiet, smooth revving, and vibration-free below about 4500 rpm which is the powerband people will use 99% of the time. But above that, it had more NVH than the Lexus 2L. Overall, I was left impressed with the Ford and somewhat disappointed with the NX's 2L and noticed how it was a little louder when I drove the NX immediately after the Fusion. I haven't tried this engine on the IS and wonder if it's any different in the NVH department.

Good report on a couple of turbo4 engines.

But it's easy to make a 4 banger smooth in the heavily-used mid-range today (up to around 4500) and therefore mainstream automakers including Toyota, Honda, Mazda, Ford do that routinely with moderately-priced cars/SUV's. Although Chrysler for example still can't figure out how to accomplish this so far, pathetic.

Another reason some automakers struggle with 4 banger smoothness across entire rev range is how they rely on balance shafts. Typically balance shafts can only be tuned to smooth a portion of the rev range, not entire rev range. So most mainstream automakers mentioned concentrate on the heavily used mid-range mentioned and consider themselves done.

But I expect that level of smoothness through entire powerband including the upper 4-6K range in a turbo 4 premium car. Mercedes does it. Audi does a pretty good job of it from what I remember driving a new A4 hard 2 years ago. I haven't driven the (more powerful) BMW turbo4, but I've seen numerous complaints about coarseness not expected in a premium car. And the BMW 4's literally sound like an old diesel when cold, lol.
 
Last edited:

mmcartalk

Expert
Messages
4,159
Reactions
2,675
I thought the 2L Turbo in the NX was pretty good in the NVH department to redline until I had a Ford Fusion 2L Ecoboost rental for a business trip a couple months back. Shockingly, the Ford's powertrain was more quiet, smooth revving, and vibration-free below about 4500 rpm which is the powerband people will use 99% of the time. But above that, it had more NVH than the Lexus 2L. Overall, I was left impressed with the Ford and somewhat disappointed with the NX's 2L and noticed how it was a little louder when I drove the NX immediately after the Fusion. I haven't tried this engine on the IS and wonder if it's any different in the NVH department.

That's an important point. The average non-enthusiast or non-aggressive driver in the U.S. rarely sees 4000 RPM, much less 4500. Ford made a smart move concentrating NVH control in the lower-bands....it is one of many things that makes the Fusion such a nice car. ;)


BTW...I considered a 2Gen Fusion before I got the car I have now. It was about #4 or 5 on the list.
 

corradoMR2

Founding Member
Messages
729
Reactions
1,124
That's an important point. The average non-enthusiast or non-aggressive driver in the U.S. rarely sees 4000 RPM, much less 4500. Ford made a smart move concentrating NVH control in the lower-bands....it is one of many things that makes the Fusion such a nice car. ;)


BTW...I considered a 2Gen Fusion before I got the car I have now. It was about #4 or 5 on the list.

You still have the Verano right? 2.4L Ecotec? How do you find the engine NVH since we're on the topic of 4 cyl NVH? :D
 

mmcartalk

Expert
Messages
4,159
Reactions
2,675
But I expect that level of smoothness through entire powerband including the upper 4-6K range in a turbo 4 premium car. Mercedes does it. Audi does a pretty good job of it from what I remember driving a new A4 hard 2 years ago.

VW/Audi was (arguably) the company that first used a mass-produced 2.0T gas engine. One reason it's so nice is that it has had years of refinement and improvements.....although, oddly, the newer twin clutch DSG trannys bolted to it don't seem as smooth and seamless as the first ones did. Go figure. o_O
 

IS-SV

Premium Member
Messages
1,886
Reactions
1,350
VW/Audi was (arguably) the company that first used a mass-produced 2.0T gas engine. One reason it's so nice is that it has had years of refinement and improvements.....although, oddly, the newer twin clutch DSG trannys bolted to it don't seem as smooth and seamless as the first ones did. Go figure. o_O

Yes, twin clutch DSG transmission past and present have a much higher incidence of complaints versus convention automatics. VW and Ford are painfully aware.

More related to the topic here are expectations for premium 4's to be smooth and refined across the entire rev range (including idle, mid-range, and to redline). This expectation is especially true for loyal Lexus, Mercedes and BMW drivers who have owned smooth/refined and sweet-sounding 6 and 8 cylinder engines for years. I personally have that expectation too in 2016.
 

mmcartalk

Expert
Messages
4,159
Reactions
2,675
You still have the Verano right? 2.4L Ecotec? How do you find the engine NVH since we're on the topic of 4 cyl NVH? :D

Typical of many other engines in this class. Reasonably smooth for a larger-displacement four-banger, with some engine noise when cold (noticeably less when warm) and as RPMs climb. No noticeable vibration at idle, but sometimes some very light vibration at low-mid-range. Much of the actual engine noise is damped out of the cabin, not by the engine itself, but by Buick's well-known (and effective) Quiet Tuning, which uses many layers of sound-insulating materials (adding, of course, to the car's weight). Given the choice, though, I would have preferred a small V6 like the Lexus/Infiniti 2.5L and some slightly higher-profile tires on smaller wheels...those are the only things I'd improve on. The rest of the car is almost perfect....a superb small car for the price.
 

mmcartalk

Expert
Messages
4,159
Reactions
2,675
Yes, twin clutch DSG transmission past and present have a much higher incidence of complaints versus convention automatics. VW and Ford are painfully aware.

My point was that the first VW/Audi non-conventional DSG's themselves were like butter.....then, for some reason, got rougher after that. I don't know why that happened.....unless it was in the programming. But, as you note, I won't get too far off-topic.

More related to the topic here are expectations for premium 4's to be smooth and refined across the entire rev range (including idle, mid-range, and to redline). This expectation is especially true for loyal Lexus, Mercedes and BMW drivers who have owned smooth/refined and sweet-sounding 6 and 8 cylinder engines for years. I personally have that expectation too in 2016.


Hard to beat the BMW in-line 6s for smoothness/power and sweetness.....though I owned a Lexus IS300 with an also-superb inline 3.0L 6 (same basic block, BTW, that was in the 90's-vintage Supra). Its only real problem was that it sucked gas like the 4.0L V8.
 

Bulldog 1

Follower
Messages
380
Reactions
387
Mmhmmmm. I thank you all for your endorsement.
If I wanted an anemic, vibrating 4-cylinder, I could have bought anything German or General Motors.
Another money grab to pay for an upgrade. Sigh.
 
Messages
17
Reactions
20
Good report on a couple of turbo4 engines.

But it's easy to make a 4 banger smooth in the heavily-used mid-range today (up to around 4500) and therefore mainstream automakers including Toyota, Honda, Mazda, Ford do that routinely with moderately-priced cars/SUV's. Although Chrysler for example still can't figure out how to accomplish this so far, pathetic.

Another reason some automakers struggle with 4 banger smoothness across entire rev range is how they rely on balance shafts. Typically balance shafts can only be tuned to smooth a portion of the rev range, not entire rev range. So most mainstream automakers mentioned concentrate on the heavily used mid-range mentioned and consider themselves done.

But I expect that level of smoothness through entire powerband including the upper 4-6K range in a turbo 4 premium car. Mercedes does it. Audi does a pretty good job of it from what I remember driving a new A4 hard 2 years ago. I haven't driven the (more powerful) BMW turbo4, but I've seen numerous complaints about coarseness not expected in a premium car. And the BMW 4's literally sound like an old diesel when cold, lol.

Yeah never understood the strange idle of many BMW engines. Even the last generation M5's V10 was no exception.
 
Messages
17
Reactions
20
My point was that the first VW/Audi non-conventional DSG's themselves were like butter.....then, for some reason, got rougher after that. I don't know why that happened.....unless it was in the programming. But, as you note, I won't get too far off-topic.




Hard to beat the BMW in-line 6s for smoothness/power and sweetness.....though I owned a Lexus IS300 with an also-superb inline 3.0L 6 (same basic block, BTW, that was in the 90's-vintage Supra). Its only real problem was that it sucked gas like the 4.0L V8.

My opinion is programming. My days of working in the service department of a VW dealer showed that. Earlier generation DSG's compared to the latest generation was like night and day however not much change to the actual transmission. Dual clutch set up with clutch packs that eventually will need to be replaced. $300+ transmission service at every interval (expensive fluid), and the clutch packs...no idea how much that would end up costing. At the end of the day it is still a manual transmission that's electronically controlled, and you can tell that feeling during low speed take off and slow driving.

A quality DSG is very expensive if you tried to make one keep up with Lexus' reliability standards, as with many manufactures, traditional transmissions with 8 speeds or more can shift nearly as fast but delivery much higher reliability, and smoothness at low speeds. No idea but i'm sure the 6 Speed Single Clutch transmission in the LFA was a fortune.

Acura has taken a good concept that I think could catch on, instead of using clutch packs it uses a DSG connected to a torque converter like a normal transmission. So still get lighting quick shifts but the smoothness and reliability of a traditional transmission.