Lexus IS250 4GR-FSE Engine Carbon Build-up (merged threads)
#571
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What you want to do is use a hose connected to the manifold. The brake booster is one possibility, but generally if there is a smaller hose, use it. Put the hose into your water source and have an assistant raise rpm to about 2500 rpm.
If you're really worried about it, you can put a restrictor in the hose to slow the water flow, but again, it's really difficult to hydrolock an engine without completely submerging the intake.
If you're really worried about it, you can put a restrictor in the hose to slow the water flow, but again, it's really difficult to hydrolock an engine without completely submerging the intake.
If you spray water inside the intake by yourself and some goes wrong...you're on your own. The best way is drive the heck of the car and burn it out.
#572
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Driving it won't do anything for the intake valves. There's nothing to clean them because the fuel isn't going down the intake.
Also, the chemical spray could easily reduce the effective octane in the cylinder and cause detonation. Many of the lighter hydrocarbons have great solvent ability, but very low octane numbers. Water does not affect octane and actually reduces octane requirements for any engine.
Also, the chemical spray could easily reduce the effective octane in the cylinder and cause detonation. Many of the lighter hydrocarbons have great solvent ability, but very low octane numbers. Water does not affect octane and actually reduces octane requirements for any engine.
Last edited by lobuxracer; 10-13-11 at 09:44 AM.
#574
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What you want to do is use a hose connected to the manifold. The brake booster is one possibility, but generally if there is a smaller hose, use it. Put the hose into your water source and have an assistant raise rpm to about 2500 rpm.
If you're really worried about it, you can put a restrictor in the hose to slow the water flow, but again, it's really difficult to hydrolock an engine without completely submerging the intake.
If you're really worried about it, you can put a restrictor in the hose to slow the water flow, but again, it's really difficult to hydrolock an engine without completely submerging the intake.
Thanks for the info Lobu
#575
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Is it proven that it is indeed EGR that causes the carbon build up? or is it just a speculation?
If it is the fuel or oil vapor from PCV then the valve closer to the PCV would have more deposit than the other, whereas if it is the EGR the carbon buildup would be fairly even. Also I'm not sure how much EGR is used today especially with variable valve controlled engine, as they can always reduce intake instead of pumping exhaust back to the intake (more work).
Regarding to ring replacement, it could be that a stuck ring is causing excessive blow by that causes more build up. I remember Saturn has a lot of problem with ring design that causes excessive oil burning and many engine died because owner didn't top off on a regular basis.
If it is the fuel or oil vapor from PCV then the valve closer to the PCV would have more deposit than the other, whereas if it is the EGR the carbon buildup would be fairly even. Also I'm not sure how much EGR is used today especially with variable valve controlled engine, as they can always reduce intake instead of pumping exhaust back to the intake (more work).
Regarding to ring replacement, it could be that a stuck ring is causing excessive blow by that causes more build up. I remember Saturn has a lot of problem with ring design that causes excessive oil burning and many engine died because owner didn't top off on a regular basis.
#576
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EGR is done with cam timing. No extra valves or plumbing required, all done with software. There's no indication the deposits are not evenly distributed, and they don't look like oil anyway. They're dry carbon.
#577
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Good point about not getting extended warranty right now, let's wait and see.
I wonder when this issue surfaced. If Lexus was aware of this issue and didn't make any remedy for a few years, it would be a real shame.
I wonder when this issue surfaced. If Lexus was aware of this issue and didn't make any remedy for a few years, it would be a real shame.
Last edited by freeflight; 10-22-11 at 08:52 AM.
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yes, i'd like to know this. I went to the dealership not too long ago and they said they could not duplicate the problem, so there was NO problem. Anyone know how to duplicate it, how to go about getting a fix?
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Read teh thread and it seems the build-up prblem is due to the engine being DI, and a common problem on many DI engines. I have not had any of the symptoms described in the posts, but I am coming up to the end of my warranty in the new year. Any recommended prevention or maintenance I can ask for at the dealer at my final visit before the warranty is up?
#581
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Read teh thread and it seems the build-up prblem is due to the engine being DI, and a common problem on many DI engines. I have not had any of the symptoms described in the posts, but I am coming up to the end of my warranty in the new year. Any recommended prevention or maintenance I can ask for at the dealer at my final visit before the warranty is up?
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No. The basic warranty. If powertrain warranty will cover it, then I'll be happy to keep driving for another two years. Still, is their no prevention possible? From what I read, this is a design flaw in all DI engines.
#584
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I'm still baffled by the lack of help in part of Lexus on this issue. Mostly because a lot of people are coming to the end of their powertrain warranty, as far as mileage is concerned.
I've devised a method that's worked twice in the past. Throwing a check engine light on behalf of engine misfires.
The first step to getting this LSB warranted by Lexus is simple, baby your car & do several short trips every week, short I mean 5 to 10 min drives.
Next step is to pay attention to your car every time you come to a complete stop at a red light or stop sign. If and when you notice your car acting like it's about to stall, immediately drop the gear to N (Neutral) and rev up the engine to red line for a few seconds consecutively. Let it bounce off the rev limiter, don't worry these cars have a cut off so you won't be doing any harm.
If done correctly at the moment you put the car into D (Drive) it should throw a misfire witch will generate a check engine light.
Quickly proceed to your nearest dealership and have them take care of your concern.
This has been a service announcement in case you didn't know![Big Grin](https://www.clublexus.com/forums/images/smilies/biggrin.gif)
Please note, this method mentioned here is only for purposes of having the dealer acknowledge your concern. It's meant for those who have been battling the problem and spending much of their hard earned cash on injector cleaners, fuel system cleaners, and other expensive bandaid fixes. Not to mention dealerships offering to do the top engine cleaning as a "charge service". The dealer cannot try to duplicate a check engine code with misfires as it's stored in the computer immediately after it happens.
I've devised a method that's worked twice in the past. Throwing a check engine light on behalf of engine misfires.
The first step to getting this LSB warranted by Lexus is simple, baby your car & do several short trips every week, short I mean 5 to 10 min drives.
Next step is to pay attention to your car every time you come to a complete stop at a red light or stop sign. If and when you notice your car acting like it's about to stall, immediately drop the gear to N (Neutral) and rev up the engine to red line for a few seconds consecutively. Let it bounce off the rev limiter, don't worry these cars have a cut off so you won't be doing any harm.
If done correctly at the moment you put the car into D (Drive) it should throw a misfire witch will generate a check engine light.
Quickly proceed to your nearest dealership and have them take care of your concern.
This has been a service announcement in case you didn't know
![Big Grin](https://www.clublexus.com/forums/images/smilies/biggrin.gif)
Please note, this method mentioned here is only for purposes of having the dealer acknowledge your concern. It's meant for those who have been battling the problem and spending much of their hard earned cash on injector cleaners, fuel system cleaners, and other expensive bandaid fixes. Not to mention dealerships offering to do the top engine cleaning as a "charge service". The dealer cannot try to duplicate a check engine code with misfires as it's stored in the computer immediately after it happens.
Last edited by XhyDra; 11-09-11 at 11:49 AM.
#585
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That is awesome....thanks xhydra....although my service advisor has always taken my word for it.
Couple of months back went to Park Place Lexus, told my advisor David Williams that cars seems like stalling every now and then. He says "OK" and gets the carbon cleanup procedure done. Simple.
Couple of months back went to Park Place Lexus, told my advisor David Williams that cars seems like stalling every now and then. He says "OK" and gets the carbon cleanup procedure done. Simple.