Lexus IS250 4GR-FSE Engine Carbon Build-up (merged threads)
#469
Lexus Champion
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I think many people on here have F-Sport Intake and Springs and they don't have the steering vibration issue. It would be baseless for the dealer to blame the problem on them. Ask them for proof that the mods caused the problem.
I have F-sport intake but no springs yet... I don't have vibration problems.
@HERBos - if you encounter the carbon build-up symptoms, the dealer are required to fix it if you are under warranty. That is what the TSB is for. I would think it take a couple of hours to perform the engine clean. You may have to leave your car for a day.
I have F-sport intake but no springs yet... I don't have vibration problems.
@HERBos - if you encounter the carbon build-up symptoms, the dealer are required to fix it if you are under warranty. That is what the TSB is for. I would think it take a couple of hours to perform the engine clean. You may have to leave your car for a day.
#470
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For the record... I'm at 50k and have yet to have symptoms of carbon build-up.
From what I have read- its due to the lack of port injection during part open throttle ... where the exhaust gas gets recirculated and fed back into the intake for a cleaner burn (?) - this is where the carbon hits the valves, and there is no port injectors to keep it from sticking. Hence... no problems for the IS350 or F.
I drive aggressively... so less POT for me (and less build up - assuming the theory is true
)
From what I have read- its due to the lack of port injection during part open throttle ... where the exhaust gas gets recirculated and fed back into the intake for a cleaner burn (?) - this is where the carbon hits the valves, and there is no port injectors to keep it from sticking. Hence... no problems for the IS350 or F.
I drive aggressively... so less POT for me (and less build up - assuming the theory is true
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#471
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From what I have read- its due to the lack of port injection during part open throttle ... where the exhaust gas gets recirculated and fed back into the intake for a cleaner burn (?) - this is where the carbon hits the valves, and there is no port injectors to keep it from sticking. Hence... no problems for the IS350 or F.
#473
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I own an IS350 (port injectors) and I have the carbon build up issue, which makes itself known every day. I know that IS350's aren't represented in this thread too well, due to having port injectors, but I'm one of the few that is experiencing this problem. I have had a top engine clean completed by Lexus and have added fuel injector cleaner to 2 tanks of gas over the course of a month, but the rough idle remains. If the rough idle issue doesn't stem from carbon build up, I'm at a loss.
Keep us updated!
#474
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I own an IS350 (port injectors) and I have the carbon build up issue, which makes itself known every day. I know that IS350's aren't represented in this thread too well, due to having port injectors, but I'm one of the few that is experiencing this problem. I have had a top engine clean completed by Lexus and have added fuel injector cleaner to 2 tanks of gas over the course of a month, but the rough idle remains. If the rough idle issue doesn't stem from carbon build up, I'm at a loss.
#475
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The fact you did the thing that all the 250 owners report as clearing up the issue (until it returns many thousands of miles later) and it did not fix the problem suggests that you do not have the same carbon build up problem and that something else is going on with your car.
Kurtz I'm in the process of getting the nitrous kit setup. From a little reading around I got from some different forums, there was mention about nitrous cleaning valves, spark plugs, and intake manifolds. I hope this turns out to be a viable solution. Although before I get anything setup I'm doing one more top engine cleaning.
#476
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Is cleaning the exhaust valves something I could do myself or should I have a professional look into it first? I'm really hesitant to take it back to the dealership since they were so difficult to work with.
#477
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Unfortunately it's not something you can clean or quick DIY. They need to be replaced, so your best bet would be to have another dealership look at your problem. It has been documented before where the exhaust valves were to blame for carbon buildup symptom type issues.
#478
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** putting on Kevlar vest **
** putting on my Flame retardant suit **
I don't know what the hell I was thinking when I did this, but I did do it and not sure if the results I am seeing are a direct result of what I did or not.
I purchased a big bottle of MMO (Marvel Mystery Oil) and used it for 4-5 gas tanks consecutively in January 2011. I also poured in couple of bottles of Gumout in between. Then I went out for a month of vacation in February 2011 and when I returned in March 2011, and fired up my beloved IS250, it sputtered and coughed and finally started up.
Since then I have not had the idle dropping below 500rpm incident happen again all trough March and half way through April now. While I can very quickly reach the most obvious conclusions and declare MMO FTW and declare myself victorious (ala GWB.), I am still a skeptic and want opinions, ideas, and a discussion as to what happened here.
** putting on my Flame retardant suit **
I don't know what the hell I was thinking when I did this, but I did do it and not sure if the results I am seeing are a direct result of what I did or not.
I purchased a big bottle of MMO (Marvel Mystery Oil) and used it for 4-5 gas tanks consecutively in January 2011. I also poured in couple of bottles of Gumout in between. Then I went out for a month of vacation in February 2011 and when I returned in March 2011, and fired up my beloved IS250, it sputtered and coughed and finally started up.
Since then I have not had the idle dropping below 500rpm incident happen again all trough March and half way through April now. While I can very quickly reach the most obvious conclusions and declare MMO FTW and declare myself victorious (ala GWB.), I am still a skeptic and want opinions, ideas, and a discussion as to what happened here.
#479
Lexus Test Driver
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any negative effects from doing this engine cleaning ...
I have made an appointment with the dealer to do it
I have experience symptoms of the build up but not severe vibration and the shaking and shudder occurs probably once every few months ..
I have 24k miles on my car and I am not sure if its too early to do it
I have made an appointment with the dealer to do it
I have experience symptoms of the build up but not severe vibration and the shaking and shudder occurs probably once every few months ..
I have 24k miles on my car and I am not sure if its too early to do it
#480
![Default](https://www.clublexus.com/forums/images/icons/icon1.gif)
** putting on Kevlar vest **
** putting on my Flame retardant suit **
I don't know what the hell I was thinking when I did this, but I did do it and not sure if the results I am seeing are a direct result of what I did or not.
I purchased a big bottle of MMO (Marvel Mystery Oil) and used it for 4-5 gas tanks consecutively in January 2011. I also poured in couple of bottles of Gumout in between. Then I went out for a month of vacation in February 2011 and when I returned in March 2011, and fired up my beloved IS250, it sputtered and coughed and finally started up.
Since then I have not had the idle dropping below 500rpm incident happen again all trough March and half way through April now. While I can very quickly reach the most obvious conclusions and declare MMO FTW and declare myself victorious (ala GWB.), I am still a skeptic and want opinions, ideas, and a discussion as to what happened here.
** putting on my Flame retardant suit **
I don't know what the hell I was thinking when I did this, but I did do it and not sure if the results I am seeing are a direct result of what I did or not.
I purchased a big bottle of MMO (Marvel Mystery Oil) and used it for 4-5 gas tanks consecutively in January 2011. I also poured in couple of bottles of Gumout in between. Then I went out for a month of vacation in February 2011 and when I returned in March 2011, and fired up my beloved IS250, it sputtered and coughed and finally started up.
Since then I have not had the idle dropping below 500rpm incident happen again all trough March and half way through April now. While I can very quickly reach the most obvious conclusions and declare MMO FTW and declare myself victorious (ala GWB.), I am still a skeptic and want opinions, ideas, and a discussion as to what happened here.