leg3ndary

I just traded my POS 2011 IS250. I am so happy i got rid of it. I spoke to a 3rd party Lexus specialist in Houston and he was in the same line of thinking as me. My car only had 50K miles on it and I experienced rough idle 5 or 6 times in the last 8 months.

The rep with the 3rd party repair shop was in complete agreement with my assessment that Lexus has done nothing about this problem (changing piston rings wont help). This could prolong the life and reduce serious damage to the crankcase, but it does nothing to protect the valves. I even think it can make the valve issue more pronounced because all the carbon deposits remain in the cylinder and is forced out by the exhaust and will deposit even more on the intake port.

He even said that nothing can be done with preventative maintenance and 1/3 of all 4GR FSE engines are affected (dont like those odds)

If anyone is in the same boat with a 250 and low miles, do yourself a favor, trade it in and get a 350. The dual injection system works with engine preservation and you can expect your car to last well beyond 100K miles.

Jeff Lange

iTrader: (1)

I think this may be the first 2011 I've heard of having the issue, and at a very low mileage too. My 2011 had just over 60k miles on it without issue and when I pulled the engine it still looked relatively decent, though not as clean as non-DI engines I've pulled apart obviously.

Jeff

Bkhectic

I hope not. It's not supposed to happen to 2011 and up. I have a 2012 and I have felt a quick lil jerk just a few times before but it might be me just *****ing about it maybe it was just because I was running the AC or Heat. I experienced it at full stop at Red lights with the gear on drive. Never on neutral. Other than that haven't had any signs or carbon build up. I hope the tiny jerks is not signs of beginning stages

RandyIS250

You guys are so uptight on Carbon build up thingy, carbon builds up happen on every new or old car once it's aged, you can't expect your car runs like new when its 5-7 years old, sometimes its fuel problem, exhaust problem, spark plugs problem, coil problem air ratio problem and vaccum hose leaks, most of stuffs on your car affect your car's performance.

Guy up there say his 2011 IS250 gets carbon build up and I totally DO NOT AGREE" it's cannot be, look at those 2006 and 2007 IS250, search the CL and Google how many 2006-2008 got carbon build up ? AWD Car gets a little of shaky when in D stop at the Light, When vibrating the Engine or Transmission mount going bad, carbon build up feels like when Coil is bad they go missfiring and Engine Light on.

To prevent carbon builds, run it on Premium Gas, put a bottle of fuel injector in gas tank once awhile, drive like a Pro Racer use S sport mode and gear once in awhile, you got push hard to Accel to 4-5k RPM,

turn down all windows you will smell that carbon burns, that means it's good, hey that burn is different to oil burn ok Lexus uses performance Engine on their car so you guys need to drive like Fast n Furious, if you drive like an old Man, you get carbon build up way faster, if you scare of Speed drive a Yaris !

Some members on here don't believe this method helps with carbon build up, same like they say dealership told them don't change Transmission fluid. Here some explanation

2 , Why all car has Exhaust system ?
1, Why your car consuming fuel ?
3, Why we need Emission Control ?

Only Electric car don't have Carbon Build up !

azari

Leg3endary,

Did you get your car diagnosed at a Lexus dealership as having carbon build up or did you preemptively sell the car after having those episodes of rough idle, thinking it might be carbon build up?

leg3ndary

I took it in for a diagnosis and it came back negative I also did their stupid *** fuel treatment service.1 month later, I was at a light and rough idle again, this time with my wife in the car who felt the same thing (I felt rough idle at least 4 times in the span of 7 months). The only change made on this engine are the piston rings. It is still TBD if that is the correct fix but I highly highly highly doubt it will do anything. Common sense says that the crankcase will not receive build-up as fast as 80K miles, but the valves are toast and I think the piston rings will only exacerbate the valve issue (less carbon leaking into the crankcase, more carbon remaining in the piston chamber and caking onto valves at 1000+ degrees Fahrenheit -- someone please validate this assumption..)

I spoke to a third party Lexus specialist about the issue and the only thing he had to say is keep making noise with Lexus until they fix it. I even asked if they walnut clean or if he knows anyone who can walnut clean and he advised against that. He basically said that there is nothing that I can do, all he said is keep making noise with Lexus and see if they fix it. The second specialist i spoke to said 1 in 3 of these cars has this problem (really ****ty odds). My car only had 49K miles and I suspect a lot of 2011+ owners have similar miles or less, that's why no one has been posting about it or heard about it.

I didn't want to take the chance with a dead engine so I got rid of it.

leg3ndary

You must be the lucky 2/3s that does not have this issue..

I used nothing but premium fuel, had a fuel treatment done as a follow-up to my diagnosis, and still had rough idle. I drive the **** out of my cars, and the IS250 was no exception (well beyond 4 to 5K on the RPM meter). I don't think that WOT is a fix to this problem. It is the inherent engine design of all DI platforms; hence the biggest reason I avoided BMW/Audi and some Mercs. I was naive enough to think that Lexus had DI figured out and went for the IS instead.

Like most buyers of the Lexus brand, we want a car that is dependable, relatively affordable to its peers and something that will last 100K+ miles. I got the first two with the IS, not sure about the third.

Most 2011+ IS's have less mileage than the 07-08 MY and I bet there will be more and more people complaining about this for the 2011+ MY in the near future.

In any case, I cut my losses, got a 3.5 dual-inject engine and am much happier =D.

leg3ndary

If I had the tools to take a part my engine, I would have done the same as you. There is on real way for me to validate the extent of carbon build-up (if any), but I didn't want to take chances. I want a car that will last well above 100K miles. I spoke to two Lexus specialists and a master mechanic from Lexus. Here is the info I got.

1.) There is nothing you can do, make noise with Lexus and see if they make a fix
2.) Install an oil catch can, but there is a possibility that you will damage the engine
3.) 1/3 of all 4GR-FSE engines have carbon build-up issues

Bear in mind, I never knew about this issue until I had rough idling at the light one morning and I was wondering what that was, so I Googled it. I am not a fan-boy of the car, I wanted an entry luxury sedan at an affordable price, which led me to an IS250.

RandyIS250

I believe you because u said 3 out of 1 get carbon build ups, more or less all will have these problem, i wanted IS350 but somehow end up with IS250, my brother said drive it for 2 years and get rid of it.

Jeff Lange

iTrader: (1)

Not like in the IS250 or other cars that use direct injection.

This agree with to an extent. It seems like whenever someone with an IS250 has any rough running issue, it's immediately assumed to be carbon build-up, when in fact there are many issues that can cause rough running. That's why diagnostics are important to verify the actual cause of the issue. The one nice thing about the IS250 is that it has almost no vacuum lines.

Unfortunately none of those methods will help prevent carbon build up in a direct-injected engine. Fuel never touches the areas where the carbon build up occurs. That's the whole issue with the IS250 to begin with. Running fuel cleaner, better fuel, pushing the engine harder will all have little to no effect on how the carbon will build up on the valves.

That's definitely true, but some engine designs are more prone to excessive carbon build up. The IS250 is one of them, unfortunately.

Jeff

jgarrido

iTrader: (1)

Jeff ,Install an oil catch can is good?

Jeff Lange

iTrader: (1)

To know for sure you'd have to have 2 of the exact same cars, ideally from new, one with the can one without and drive them identically (or close to it) in the same regions and then compare the carbon build-up to see if there is a difference.

That said, it certainly won't hurt, and it very well may help, so I don't think they're a bad idea at all.

Jeff

azari

Leg3ndary,

I think the fact that your car's diagnosis for carbon build up came back negative is pretty promising for us 2010 and newer IS250 owners. A rough idle can be caused by a number of factors. So far I haven't seen any diagnosed cases of carbon build up with the 2010 (modified pistons) and newer cars; at least not yet! Mine is a 2011 with over 80k miles and runs great. Hopefully it'll stay that way!

MWIS350

Also trade my in last year but it was running ok. Now we owe IS350 and ES350.

MWIS350

All direct fuel injectors car like IS250, Audi, BMW have carbone build up issue.