Scary problem - unexplained acceleration in my is250
#16
Lexus Test Driver
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I have NEVER had a check engine light on yet. When I explained the problem to the dealer, they also mentioned that maybe the rpm's were high because it was trying to warm up....HOWEVER...it is not supposed to be enough to allow your car to drive at 40mph for miles. It also should not launch forward at a stop light (not enough to burn tires, but enough to make it uncomfortable). They are keeping the vehicle for another day to do more tests.
I have had several cars before, including other luxury and sports car. I am from Connecticut and have never had a car do this before. My BMW 335i didn't do it. My 350z didn't do it. If this is what Lexus considers normal and safe, then I'm selling the car as soon as I get it back from the shop.
I have had several cars before, including other luxury and sports car. I am from Connecticut and have never had a car do this before. My BMW 335i didn't do it. My 350z didn't do it. If this is what Lexus considers normal and safe, then I'm selling the car as soon as I get it back from the shop.
You ask if 1500 RPM is enough to get these vehicles moving...well that answer is yes. When I go to the drag strip, I power brake my car to about 1000-1500 RPM for the best launch possible. So the launch I aim for at the drag strip is the same you feel when your car's idle is at 1500 RPM when it is warming up...even after the car has warmed up, the idle speed is enough to get the vehicle moving to at least 20mph
The reason you think your other vehicles didn't do this is probably because you didn't notice that they did this. On another cold winter day, jump in a friend's non-Lexus and you will notice they all do the same thing. I am sorry this is so frightening to you, maybe a vehicle with less low end torque and less aggressive low end gearing is more suited for you... jk
#18
Lexus Champion
How does a luxury car keep a constant speed for you, if you take your foot off the gas, and don't have the cruise control on?
#19
Lexus Test Driver
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What I was trying to point out is that these vehicles will not downshift to try and slow the car down if you take your foot off the gas...they will keep the highest gear possible to allow the vehicle to glide almost with the least resistance possible, then once re-applying the gas it will find the correct gear per the throttle input
#21
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So you're telling me that every single one of your cars, when cold, can drive on its own at 40 to 50 mph? I highly doubt it....and if so, please go take a video and post it. The NHTSA would flip if this was a standard among Lexus.
And to the comment about getting another car with lower torque....this lexus is one of the lowest I've ever owned. Never have I experienced this with another brand. I've also talked to several mechanics and 2 engineers from Ford who say this shouldn't be happening.
And to the comment about getting another car with lower torque....this lexus is one of the lowest I've ever owned. Never have I experienced this with another brand. I've also talked to several mechanics and 2 engineers from Ford who say this shouldn't be happening.
#22
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I don't think the 40-50mph is normal either. I would have to see a video of the redlight issue you were talking about, but I do have to put a decent amount of pressure on the brake while the car is still not up to temp. Otherwise it will want to start moving again. My car does have leave on its own while cold, but I wouldn't consider it harsh.
#24
Wish the video was longer. My car can coast around those speeds for a bit if the conditions are right (level road, going straight, etc.). I too have to press the brake fairly firm when I get started in the morning from a cold start. If I take my foot off the brake I feel like the car will accelerate to 15-20mph, it's just ready to go.
I've been able to get my last car, a Ford Fusion V6, to coast at speeds too without my foot on the gas. But I don't see in the video where there's an "acceleration" issue. Maybe there is a problem with it's ability to 'cruise' without cruise control on but like I said, the video is really short. I don't see the major issue (yet), and I don't see where it's anything like what happened with Toyota (which more or less was proven to not be a real thing anyways).
I've been able to get my last car, a Ford Fusion V6, to coast at speeds too without my foot on the gas. But I don't see in the video where there's an "acceleration" issue. Maybe there is a problem with it's ability to 'cruise' without cruise control on but like I said, the video is really short. I don't see the major issue (yet), and I don't see where it's anything like what happened with Toyota (which more or less was proven to not be a real thing anyways).
#26
Lexus Champion
I tried this out in my car today (2014 IS350). Car sat in the cold for 10 hours, ambient around 35 deg F. I started it up and put it in drive within 1 minute. Couldn't even get it to maintain 20 mph without using the gas pedal, despite the elevated RPMs. Not sure what's up with the OP's car, but I can't believe this is normal.
#27
Driver School Candidate
Nothing like the Toyota issue...and you do not have unintended acceleration. BTW, Toyota was completely exonerated from all of that nonsense. Even NASA couldn't find an issue with their software. And every case I have seen, the data from the car's "black box" showed the driver was hitting the gas and not the brake pedal.
It is normal for your RPMs to rise slightly sometimes. If the car is cold, it will raise RPMs to warm up quicker. If the A/C compressor turns on, it will rise slightly to compensate for the load on the motor. If you said 3,000 RPMs, then there would be concern.
And for the record, the car will move forward when you are in drive and take your foot off the brake...
It is normal for your RPMs to rise slightly sometimes. If the car is cold, it will raise RPMs to warm up quicker. If the A/C compressor turns on, it will rise slightly to compensate for the load on the motor. If you said 3,000 RPMs, then there would be concern.
And for the record, the car will move forward when you are in drive and take your foot off the brake...
I doubt that this is the same issue, but just take it to a dealer and have it fixed. Cars decelerate when you release the gas not stay the same or accelerate in speed.
#29
Lead Lap
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This is a NORMAL thing. I noticed on your temp display that its 38 degrees out and your vehicle isn't fully warmed up. what's happening is your engine and transmission are warming themselves up faster by idling at higher RPMs. And yes, if you happen to be in Drive while its still not warmed up it will be moving a little quicker than you will be used to, especially when you release the brake pedal from a full stop.
#30
Lexus Test Driver
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Guys, this is not normal. My IS350 does the same thing when it's below 50 and not fully warmed up. When I let go of my gas pedal, it will maintain speed and not even slow down. It's almost as if my foot was stilling lightly pressing the gas. It will almost coast at 1500 RPM+. I know this is not normal since I work at a Acura/Lexus dealer and I've taken their loaners to get gas or a snack from the nearby 7 Eleven and I did not notice it happening on the loaner cars. Even when cold, they coast at about 1100 RPM and slow down when I let off the gas.. This started happening to me last winter and only occurs in cold weather. Definitely not carbon build-up since I had a new motor put in this summer and the throttle body is clean, so is MAF. I do have a CEL with code P0606 which is a faulty ECU but that too has been replaced about a year ago when this started happening but it didn't fix it.
OP, let us know what Lexus says. I've had the techs at my work check it out and none of them can figure out what's wrong and claim it's "normal" but still not 100% normal.
OP, let us know what Lexus says. I've had the techs at my work check it out and none of them can figure out what's wrong and claim it's "normal" but still not 100% normal.