Grambo

So my 2013 is250 F-sport with 8,500 miles is in the shop right now getting tested. About a week ago, my car started acting funny. At stop lights/signs, the rpms would jump up from idle (600rpms) to about 1,100rpms and launch me forward when I left off the brake. THEN, I was driving down the road at 40mph and left off the gas. My car continued to drive at 40mph and 1,600 rpms. I drove like that for miles without having to touch the gas pedal. This has happened several times since then and I recorded videos on my phone. I'm going to upload them to YouTube and post links here so you can check them out. This sounds identical to the Toyota issue a few years ago and yes....I checked my floor mats.

Any ideas???!

Note: This happened about 5 minutes into a drive. The outside temp was around 38 degrees and the engine temp. shows it 1/2 way to normal operating temp. This has happened approx. 5 other times during driving in the last few days, some of which temperatures were in the 50's-60's and after the engine was completely warm.

TimboIS

No it doesn't.

quick123

iTrader: (2)

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...

Grambo

Of course it will because of the base engine idle....however, when driving around for 10 minutes, the car should not be at 1,500 rpms at idle, especially when it's 55-60 degrees outside. Nor should it stay at 1,500 rpms when you take the foot off the gas pedal at 40mph for miles.

reyoasian

iTrader: (2)

check your cruise control? lol

Noeh

iTrader: (3)

Try resetting the ECU by disconnecting your battery for few mins. If the problem persists inspect your TB

TimboIS

That is NOT going to help in anyway!

Most likely it's rough idle caused by carbon build-up.

Noeh

iTrader: (3)

Don't jump on conclusions, it's not like you worked on his care and know for sure. Speaking from experience, I had a bad throttle body cause weird idle before. Also carbon build-up on a 2013 IS with less than 10k miles? That's a lemon!

604GSE21

owners manual does recommend that you shift into neutral if you are sitting at the light for awhile...

tigerbalm

i'm still learning about these cars, but I've seen Idle Air Control (IAC) valves cause the symptoms. I'm not sure if these cars have that though.

quick123

iTrader: (2)

Here is the thing...have you seen any check engine lights on? Any warning lights at all? If you did, then yes you have something malfunctioning in your vehicle. If the vehicle had an abnormal idle, it would set a check engine light. If the timing was off, or there was a air/vacuum leak affecting idle, you would have a check engine light. If you don't, then most likely the car is functioning as designed and you need to get used to it.

This is a luxury vehicle, and it will try and do a lot of things for you, like keep a constant speed if you take your foot off the gas. It is not accelerating out of control like it is flooring itself. I wonder if your previous car was a manual transmission...

tigerbalm

Unless the car is set on cruise control or is still warming up it should not hold the same speed and rpm for miles as the post originator indicated in his first post. It will remain at that speed briefly but start to gradually slow within a few seconds from releasing the gas pedal. I do agree that this being a luxury car will do more things than non luxury car people are used to though.

quick123

iTrader: (2)

After really watching the video a couple times, here is what I see:

- no warning lights on
- 39 degrees outside
- engine coolant is not at normal operating temp yet
- car is not accelerating, but holding speed
- cruise control light is not on

I again will have to assume that this is just the ECU trying to get the temps up and holding a higher RPM. Once all the fluids are nice and warmed up, the idle will drop and you would not experience this.

shawnxjeon

In my car I see the RPM go up as well but I've never seen it go up to a point where it has a rough start when I leave the brake from a stop and be able to maintain 40 mph because the RPM is that high... I usually see it not shift into 6th and stay at a high RPM in 5th when I'm going 45-60 mph when the engine is cold. I will try going 40 with a cold engine and I'll let post what happens.

... Or maybe it's a ghost.

Grambo

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.