View Poll Results: Do you feel any engine vibrations at low RPM with your NX 200t?
Yes. Often
28
21.54%
Yes. Sometimes
41
31.54%
No. Not at all
61
46.92%
Voters: 130. You may not vote on this poll
NX 200t Owner Survey - Engine Vibration Poll
Lexus Test Driver
Joined: May 2011
Posts: 1,492
Likes: 12
From: PA
Shouldn't the question be "Do you feel any excessive engine vibrations at low RPM with your NX 200t?" My last car was an electric car and there was zero vibration. The NX is an ICE-based vehicle so there is always going to be some level of vibration. Technically, the results should reflect 100% "Yes. Often"
The NX is very smooth, but the Camaro has some natural unbalance as the stock cam in the LS3 is performance oriented, and the new cam I'm putting in will legit shake the car.
Intermediate
Joined: Oct 2011
Posts: 475
Likes: 10
From: Ct
Intermediate
Joined: Oct 2011
Posts: 475
Likes: 10
From: Ct
Lexus 2-Liter Engine Architecture
The Lexus in-line, four-cylinder, two-liter engine in the 2015 NX 200t includes a balance shaft with resin gearing. It uses a twin scroll turbocharger. The engine also has an air to liquid intercooler. Fuel is delivered to the engine by both port and also direct injection. The VVT-iW cam and valve timing system can allow the engine to operate in both the Otto and also Atkinson cycles. The exhaust manifold is built into the cylinder head and is cooled to keep exhaust gases from causing too much strain on this super-hot area of the engine. Let’s dive deep into this engine design now and take a closer look at every aspect of what could be the most important Toyota/Lexus engine in a decade.
Final Thoughts on the 2015 Lexus NX Turbo Engine
Having driven, heard, and seen the new Lexus turbocharged 2.0-liter engine we now know why Lexus waited so long to introduce it. It is one of the quietest, most fuel efficient engines of its type, and it is made entirely by Lexus which means that its quality, durability, and reliability will be unrivaled. Look for it to be the mainstay of the Toyota/Lexus line for the next decade or more.
The Lexus in-line, four-cylinder, two-liter engine in the 2015 NX 200t includes a balance shaft with resin gearing. It uses a twin scroll turbocharger. The engine also has an air to liquid intercooler. Fuel is delivered to the engine by both port and also direct injection. The VVT-iW cam and valve timing system can allow the engine to operate in both the Otto and also Atkinson cycles. The exhaust manifold is built into the cylinder head and is cooled to keep exhaust gases from causing too much strain on this super-hot area of the engine. Let’s dive deep into this engine design now and take a closer look at every aspect of what could be the most important Toyota/Lexus engine in a decade.
Final Thoughts on the 2015 Lexus NX Turbo Engine
Having driven, heard, and seen the new Lexus turbocharged 2.0-liter engine we now know why Lexus waited so long to introduce it. It is one of the quietest, most fuel efficient engines of its type, and it is made entirely by Lexus which means that its quality, durability, and reliability will be unrivaled. Look for it to be the mainstay of the Toyota/Lexus line for the next decade or more.
Thread Starter
Rookie
Joined: May 2015
Posts: 88
Likes: 1
From: CT
OP, the following questions:
1. Do you have AUTO on the climate control? If this is the case, I would think that you're feeling the compressor running all the time. But, I only feel it when i let off the brake. Why would that change anything if it was coming from the compressor. EDIT: tried a few things. First with ac climate control system off. ~ 650 RPM on brake. ~ 725 RPM off brake. Now with climate control on - RPM are about 725 whether on or off the brake. No matter the status of the climate control system, once I remove my foot from the brake, the car has a vibration.
2. Are you running 91+? If you aren't, you could be feeling the engine running with a little bit of knock. I am actually running 93
When you're saying "vibration", how much are we really talking? One you oddly feel in your foot, or something that makes your teeth move? Somewhere in the middle of your two examples. Its enough that I can feel it in the wheel and my seat
What RPM are you sitting at a stop? Does the RPM move at all once the car starts rolling? (i'm more concerned about it going downward) Will need to recheck RPMs. If anything, going by memory, when i release the brake and feel the vibration, I am recalling seeing the RPMs go up a little - see above in Blue
1. Do you have AUTO on the climate control? If this is the case, I would think that you're feeling the compressor running all the time. But, I only feel it when i let off the brake. Why would that change anything if it was coming from the compressor. EDIT: tried a few things. First with ac climate control system off. ~ 650 RPM on brake. ~ 725 RPM off brake. Now with climate control on - RPM are about 725 whether on or off the brake. No matter the status of the climate control system, once I remove my foot from the brake, the car has a vibration.
2. Are you running 91+? If you aren't, you could be feeling the engine running with a little bit of knock. I am actually running 93
When you're saying "vibration", how much are we really talking? One you oddly feel in your foot, or something that makes your teeth move? Somewhere in the middle of your two examples. Its enough that I can feel it in the wheel and my seat
What RPM are you sitting at a stop? Does the RPM move at all once the car starts rolling? (i'm more concerned about it going downward) Will need to recheck RPMs. If anything, going by memory, when i release the brake and feel the vibration, I am recalling seeing the RPMs go up a little - see above in Blue
Lexus Test Driver
Joined: May 2011
Posts: 1,492
Likes: 12
From: PA
The reason I asked about the compressor running is because that's another load on your underdrive pulley and extra load on the motor. If its was starving for power (like a fuel injector problem or an ignition coil issue) it would stuggle to run the compressor. Also, keep in mind, your AC compressor is always running when you have AUTO on, regardless if you have the temperature set at 75F or 32F. Its one of the reason I don't like utilizing an AUTO feature.
RPMs seem consistent, though your non-AC brake idle looks a little low.
Is your oil pressure and turbo temp normal? My oil pressure when cold is 32-33psi and upward to 60psi, and when warm, it will go down to 25-27psi. My normal turbo temp is about 180F.
My next suggestion would be to think that you might have a broken motor mount.
RPMs seem consistent, though your non-AC brake idle looks a little low.
Is your oil pressure and turbo temp normal? My oil pressure when cold is 32-33psi and upward to 60psi, and when warm, it will go down to 25-27psi. My normal turbo temp is about 180F.
My next suggestion would be to think that you might have a broken motor mount.
Driver School Candidate
Joined: Sep 2005
Posts: 44
Likes: 0
From: wisconsin
I have a 200t built 11/14, auto is always on. temps have been between 100 and 20. Octane between 87 and 93, I have not noticed any vibration at any time! Could be my nerve endings have changed with age, or my butt is fatter than I thought ! No issues at all.
10th Gear
Joined: Oct 2015
Posts: 14
Likes: 0
From: British Columbia
Thanks, Sawcer. That could explain why some people here experienced vibration.
Hey, CorradoMR2, please keep us posted when you take your car in for 16k km maintenance. Curious to know what your SA has to say about the vibration.
Hey, CorradoMR2, please keep us posted when you take your car in for 16k km maintenance. Curious to know what your SA has to say about the vibration.
Pole Position
Joined: Feb 2003
Posts: 360
Likes: 9
From: NY
The reason I asked about the compressor running is because that's another load on your underdrive pulley and extra load on the motor. If its was starving for power (like a fuel injector problem or an ignition coil issue) it would stuggle to run the compressor. Also, keep in mind, your AC compressor is always running when you have AUTO on, regardless if you have the temperature set at 75F or 32F. Its one of the reason I don't like utilizing an AUTO feature.
RPMs seem consistent, though your non-AC brake idle looks a little low.
Is your oil pressure and turbo temp normal? My oil pressure when cold is 32-33psi and upward to 60psi, and when warm, it will go down to 25-27psi. My normal turbo temp is about 180F.
My next suggestion would be to think that you might have a broken motor mount.
RPMs seem consistent, though your non-AC brake idle looks a little low.
Is your oil pressure and turbo temp normal? My oil pressure when cold is 32-33psi and upward to 60psi, and when warm, it will go down to 25-27psi. My normal turbo temp is about 180F.
My next suggestion would be to think that you might have a broken motor mount.
Driver
Joined: Aug 2012
Posts: 134
Likes: 0
From: SG
OP. I know exactly what you're experiencing. It's happened to me from day 1 which I reported in a few threads over time in this forum. The vibration is uncharacteristic of Lexus, regardless of it being a 4 cyl since the CT I had was smooth at all RPMs. I'd say it's more noticeable with cooler temps these days vs over the summer.
Conditions when the vibration occurs:
- 700-800 rpms (all other RPMS smooth)
- If the HVAC is on, slightly more vibration is felt
- engine can be warm or cold
- it is lightly felt with the Brakes engaged with your foot or via the Hold function
- it is more felt as soon as you release the brake and let the car roll before hitting the gas
- it is also felt when coming to a stop getting to the 700-800 rpm range.
- vibration is felt slightly through the seat, more so if you place your hand on the center armrest
For a recent business trip, I had a Ford Fusion rental with the 2L Ecoboost 4 cyl (similar power/torque) and I was surprised at how smooth, vibrationless, and quiet
it was especially at lower RPMs.
I have my 16k km maintenance appointment Friday. I will mention this to my SA.
@NX Owner, I'd do a video but there there is no perceptible rpm fluctuation that a video would capture, at least from my NX. RPM is very stable. My guess is an engine mount issue.
Conditions when the vibration occurs:
- 700-800 rpms (all other RPMS smooth)
- If the HVAC is on, slightly more vibration is felt
- engine can be warm or cold
- it is lightly felt with the Brakes engaged with your foot or via the Hold function
- it is more felt as soon as you release the brake and let the car roll before hitting the gas
- it is also felt when coming to a stop getting to the 700-800 rpm range.
- vibration is felt slightly through the seat, more so if you place your hand on the center armrest
For a recent business trip, I had a Ford Fusion rental with the 2L Ecoboost 4 cyl (similar power/torque) and I was surprised at how smooth, vibrationless, and quiet
it was especially at lower RPMs.I have my 16k km maintenance appointment Friday. I will mention this to my SA.
@NX Owner, I'd do a video but there there is no perceptible rpm fluctuation that a video would capture, at least from my NX. RPM is very stable. My guess is an engine mount issue.
The pursuit of F
Joined: Jul 2006
Posts: 8,296
Likes: 303
From: Toronto, Canada
@swacer - it's possible the Atkinson tech has something to do with but then everyone would experience vibration and could be argued "it's by design". But the fact that at this time, a higher 56% of the owners voted for No Vibrations while 44% voted Yes indicates this vibration is clearly not by design.
However, let's see how the numbers play out as the sampling is still fairly small.
Will do though it won't be until late next Thursday since the dealer had to reschedule on me since they thought I was only coming in for the 16k km (10k mile) service. The positive in this delay is this poll should garner more votes, making it a more reliable source of information, which I will show to my dealer.
Not an expert mechanic and Swacer or anyone else more mechanically-inclined can chime in but if I'd have to guess, it would be with the engine mounts based on the conditions I described earlier.
However, let's see how the numbers play out as the sampling is still fairly small.
Not an expert mechanic and Swacer or anyone else more mechanically-inclined can chime in but if I'd have to guess, it would be with the engine mounts based on the conditions I described earlier.
Intermediate
Joined: Oct 2011
Posts: 475
Likes: 10
From: Ct
Mine doesn't vibrate. Mine is a 6/15 build date. Be interesting to ask new IS owners.........
I own a CT200h and my NX is honestly smoother....the CT idles a tad smoother , but drivability the NX is.....otto and atkinson do contribute.
I own a CT200h and my NX is honestly smoother....the CT idles a tad smoother , but drivability the NX is.....otto and atkinson do contribute.
