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Overall I think the 3IS will be a fairly reliable car, but we seem to be getting quite a few problem threads lately for the 3IS. This car, is starting to show its age now. So things will naturally start to pop up. We are on year 5. Many of us are nearing the end of our leases or warranty period so it's fair to consider these potential areas of concern.
Here is what I think potential problem areas or concerns to watch out for based on patterns of threads lately seen here. (over past year or so) and with 2IS
It's a fairly sporty car with more demand on it. It's not exactly a Camry or ES300. So to some degree I expect these things. More features/more tech/more performance/ more problems. But they are concerns nonetheless.
F SPort Gauge Cluster - One failure, hardly constitutes an epidemic
Door actuators - Not a new issue, has been around for awhile
LED DRL units (the swooshes) - there have been some recent reports of this, could be a legit concern developing
Headlight (individual LED headlights, the drivers) - some regions didn't get the LED's during certain versions of the IS, so no worries for some...plus I don't believe anyone had reported a failure
AC/HVAC - what about it? There were reports of bad smell, but that could be self induced. The servo reset issue seemed to only plague the first couple years of 3IS.
Infotainment screen/audio/amps - seems to have plagued the early 3IS models with the old system
Charging (electrical-alternator) - what about it?
Front control arm bushings (high wear) - No one has reported worn out bushings...just worn out tires. The bushings are absolutely fine for the way they were designed...I would say the flaw is in the design, more so the rubber compound to be exact.
I just hit the 5 year mark with my 3IS and the only thing to pop up is the driver's side passanger door actuator. I still haven't fixed it yet because no one sits behind me in the car. The battery will probably be going sometime this summer thanks to the AZ heat. They don't usually last more than 3 years and I'm on my 2nd one.
Anyone more familiar with engines understand the severity of the carbon buildup noted in the thread? Seems to be a problem if Lexus is under the impression that their port injection system should have eliminated or highly mitigate carbon build-up, especially at the 60k mark.
How about the boost/vacuum regulator? That seems to be a problem with it seemingly failing every 5-10k miles. Although the part is fairly cheap, I would think that it would be a huge annoyance down the road.
Anyone more familiar with engines understand the severity of the carbon buildup noted in the thread? Seems to be a problem if Lexus is under the impression that their port injection system should have eliminated or highly mitigate carbon build-up, especially at the 60k mark.
How about the boost/vacuum regulator? That seems to be a problem with it seemingly failing every 5-10k miles. Although the part is fairly cheap, I would think that it would be a huge annoyance down the road.
There is a bulletin for the regulator, which includes an updated hose...came out end of Nov/2018. Get your new parts if you haven't done so yet.
The symptoms are noise from the valve and surging while driving under moderate to heavy throttle.
There is a bulletin for the regulator, which includes an updated hose...came out end of Nov/2018. Get your new parts if you haven't done so yet.
The symptoms are noise from the valve and surging while driving under moderate to heavy throttle.
I am aware... currently fighting the stealership on getting it replaced. They think my surging is due to my fuel.
In the issue thread, people were complaining that the revised part was also failing, but there has not been many new threads on it so perhaps it is fixed.
Forgot about the regulator. Apparently Sheddy says even with the "updated" regular, his has failed. He can correct me if i am wrong??
the other day i did feel some weird surging/jerking. it happened 4-5 times. i immediately thought boost regulator. but it hasn't came back and hasn't happened since.
Anyone more familiar with engines understand the severity of the carbon buildup noted in the thread? Seems to be a problem if Lexus is under the impression that their port injection system should have eliminated or highly mitigate carbon build-up, especially at the 60k mark.
How about the boost/vacuum regulator? That seems to be a problem with it seemingly failing every 5-10k miles. Although the part is fairly cheap, I would think that it would be a huge annoyance down the road.
That particular poster said the engines failed but he wouldn't say why. He says he doesn't want to cause false alarm. I think not saying anything is just as bad. But I suspect due to the photos showing heavily carboned intake tract and valves, I suspect this engine may have been getting misfire codes. That's just my guess.
I am aware... currently fighting the stealership on getting it replaced. They think my surging is due to my fuel.
In the issue thread, people were complaining that the revised part was also failing, but there has not been many new threads on it so perhaps it is fixed.
I know the bulletin mentions replacing the hose with the updated part as well, so I would think the hose is critical to the overall fix.
And I would agree that it's possible the updated part has failed. It has happened a few times that Toyota/Lexus has a bulletin with an updated part to fix an issue, and the new part fails in the same way...or creates a new problem.
It doesn't happen often thankfully, but it does happen.
At least the engineers now know what didn't work, and usually get it right the second time.
That particular poster said the engines failed but he wouldn't say why. He says he doesn't want to cause false alarm. I think not saying anything is just as bad. But I suspect due to the photos showing heavily carboned intake tract and valves, I suspect this engine may have been getting misfire codes. That's just my guess.
I read that thread, and that was the missing component, why did they fail?
Not saying the buildup isn't notable, but the 2IS intake valves were 10 times worse than those before they threw a misfire code...like you would need a hammer and chisel to get the carbon off.
If the vehicle threw a misfire code for that amount of buildup on the turbo motor, either the ECU is super sensitive with tighter parameters, or something else caused the codes.
All just speculation though...
The Toyota door lock actuators are junk and will fail. This is my third IS350, the first two being a 2IS and they were nothing but problems and the design seemingly hasn't changed. I replaced almost all of them in my previous two and just replace two in my 2014 Tundra. Luckily, its cheap if you're willing to open them up and just replace the little motor inside as that is what causes the issue in all Toyotas.
The LCA bushings aren't up to the task from the get go. My '06 started eating tires early on. I did an alignment, no luck. Replaced them with new OEM bushings and another alignment, no luck. I swapped to FIGS bushings and all the terrible tire wear ceased. On my next IS I just did that on about the 3rd day of ownership and never had any issues. The 3IS has the same bushings and suspension design, it is just matter of when, not if it will happen as far as I'm concerned.
The one that I don't see mentioned is the rear brake calipers. I will say that I have not touched the brakes in my 3IS yet, but I suspect the design hasn't changed either. Previously the rear brakes had a blind pin that was prone to corrosion and seizing the caliper, preventing it from sliding so it would only wear the piston side pad. Both of my previous ones had that issue so I would always take the 5 minutes to simply grease that pin any time I have the rear wheels off. But it still seems like a nonsense issue, especially considering I'm in an area with no worries of salt, snow and such.
Other than those things, I never had a single mechanical issue out of any of them all the way up 150k miles.
The Toyota door lock actuators are junk and will fail. This is my third IS350, the first two being a 2IS and they were nothing but problems and the design seemingly hasn't changed. I replaced almost all of them in my previous two and just replace two in my 2014 Tundra. Luckily, its cheap if you're willing to open them up and just replace the little motor inside as that is what causes the issue in all Toyotas.
The one that I don't see mentioned is the rear brake calipers.
Are the rear calipers a carryover from the 2IS? The rear suspension is new so I assume the brakes are different as well. I don't know for sure though. Haven't bothered to look into that.
I hated those pins. I did a rear brake job for my friend's 2IS. Was a bit of a pain but got the hang of it. Seemed a bit overcomplicated for what the pin is set out to do (assuming we're talking about the same pad retaining pin/clip/spring)
Are the rear calipers a carryover from the 2IS? The rear suspension is new so I assume the brakes are different as well. I don't know for sure though. Haven't bothered to look into that.
I hated those pins. I did a rear brake job for my friend's 2IS. Was a bit of a pain but got the hang of it. Seemed a bit overcomplicated for what the pin is set out to do (assuming we're talking about the same pad retaining pin/clip/spring)
I am not 100% as I haven't messed with the brakes on my 3IS but they do look the same. They did have a weird pin/clip/spring setup that retains the pads, but that is not what I'm talking about. There is only one bolt that holds the two pieces of the caliper together, the other is just a blind pin that the caliper slid on so there was no way to remove it. They were prone to corroding and making the rear sliding caliper immobile.
Again, I haven't been into the 3IS brakes but just looking at it, it looks the same.
EDIT: Ok, you had me curious now so I just went out and looked at the rear caliper design. They did change it to alleviate the stupid issue that plagues the 2IS.
Last edited by Tungstn-IS; Feb 5, 2019 at 03:28 PM.
^good to know. My friend and I were commenting how dumb the 2IS rear retaining spring design was as weve done brake jobs on so many different cars. On BMW's it's literally one flat piece of metal you install using your fingers. a toddler can do it. And in all of Toyota's brilliance there was this weird overly complicated spring. But i imagine i'd not want to encounter this pin you are talking about either.
toddler-friendly retaining clip on BMW rear
to Lexus's credit the 2IS/3IS front (F Sport) brakes are the easiest brakes i've ever worked on. literally only need a screwdriver and your fingers to do a pad swap.
The 2IS rear brakes were not carried over to the 3IS. The 3IS rear uses a traditional floating caliper, like the front of a 3IS 250.
The 2IS rear brakes were a bad design and prone to seizing, hence they were scrapped...live and learn.
3IS long term ownership concerns
