IS250 carbon buildup - What works? What doesn't?
08-17-17, 06:06 AM
#16
What oil do you recommend? Also, how do you use the BP's fuel system cleaner and how does that help with the carbon since the fuel never washes over the problem area on the valves?
08-17-17, 08:30 AM
#17
A few things that are rarely mentioned are:
How you use the car matters!
City cars doing short 15" trips and idling more than being ran WOT will accumulate deposits in both intake and exhaust tracks as well throughout the entire engine much quicker than a car ran 100mi a day down the interstate. The soccer car grocery getter needs more oil changes than the Interstate freeway runner.
Why has many parts:
1) Never reaching full operating temperature means fuel and water vapor in the crankcase never burn off.
2) Each time you start the car cold it runs richer to maintain a smooth idle and that extra fuel is not only deposited into the crankcase oil but also into the intake when the car is shut off.
3) Each time you turn the engine off, combustion gasses must go somewhere and SOME of the intake and exhaust valves are open. Those combustion gasses, unburned fuel, and to some extent oil vapor deposit on the valves, and intake plenum up to the throttle body. Not to mention the EGR gasses which are now in the intake all attach as a film. Over years this accumulation adds up creating a physical layer of deposits. The intake valve being cooled by fresh air coming in is the prime candidate for deposits.
4) Offsetting this build up process can be as simple as trading cars with others in your life who freeway commute and OPEN the engine up for sustained higher RPM use when fully warmed up. High velocity through the intake, combustion chamber, and exhaust, slowly removes deposits.
You see this when people stomp on the throttle and the grey cloud of ash pours out the pipes freeing the vehicle of loose deposits that accumulate during idle time and putting around.
Add fuel cleaners at least 3x a year. Especially before winter freeze sets in to reduce the chance of moisture in the fuel system freezing and leaving you stranded.
FWIW I use Techron black bottle 3x a year in everything that burns fuel.
Last little bit; the back side of the exhaust valve stays much cleaner as the combustion gasses at 1200 to 1500°F burn off deposits reducing them to ash. In addition the port velocity is much higher on the exhaust than the intake. It's why the exhaust doesn't have the same build up issues.
Bottom line is they need to reach full operating temperature AND be opened up occasionally! Grocery getters need more frequent OC than Interstate cars even tho they travel half the miles.
JM2C!
tag JJD952
How you use the car matters!
City cars doing short 15" trips and idling more than being ran WOT will accumulate deposits in both intake and exhaust tracks as well throughout the entire engine much quicker than a car ran 100mi a day down the interstate. The soccer car grocery getter needs more oil changes than the Interstate freeway runner.
Why has many parts:
1) Never reaching full operating temperature means fuel and water vapor in the crankcase never burn off.
2) Each time you start the car cold it runs richer to maintain a smooth idle and that extra fuel is not only deposited into the crankcase oil but also into the intake when the car is shut off.
3) Each time you turn the engine off, combustion gasses must go somewhere and SOME of the intake and exhaust valves are open. Those combustion gasses, unburned fuel, and to some extent oil vapor deposit on the valves, and intake plenum up to the throttle body. Not to mention the EGR gasses which are now in the intake all attach as a film. Over years this accumulation adds up creating a physical layer of deposits. The intake valve being cooled by fresh air coming in is the prime candidate for deposits.
4) Offsetting this build up process can be as simple as trading cars with others in your life who freeway commute and OPEN the engine up for sustained higher RPM use when fully warmed up. High velocity through the intake, combustion chamber, and exhaust, slowly removes deposits.
You see this when people stomp on the throttle and the grey cloud of ash pours out the pipes freeing the vehicle of loose deposits that accumulate during idle time and putting around.
Add fuel cleaners at least 3x a year. Especially before winter freeze sets in to reduce the chance of moisture in the fuel system freezing and leaving you stranded.
FWIW I use Techron black bottle 3x a year in everything that burns fuel.
Last little bit; the back side of the exhaust valve stays much cleaner as the combustion gasses at 1200 to 1500°F burn off deposits reducing them to ash. In addition the port velocity is much higher on the exhaust than the intake. It's why the exhaust doesn't have the same build up issues.
Bottom line is they need to reach full operating temperature AND be opened up occasionally! Grocery getters need more frequent OC than Interstate cars even tho they travel half the miles.
JM2C!
tag JJD952
Last edited by 2013FSport; 08-17-17 at 08:45 AM. Reason: Added content
The following 2 users liked this post by 2013FSport:
IWasHungry (10-14-17),
lexus4nxtc (10-06-20)
08-17-17, 08:35 AM
#18
Here is an article you can read by a GM guy. However he fails to address the importance of the oil.
http://thechronicleherald.ca/wheelsn...rect-injection
08-17-17, 08:42 AM
#19
A few things that are rarely mentioned are:
How you use the car matters!
City cars doing short 15" trips and idling more than being ran WOT will accumulate deposits in both intake and exhaust tracks as well throughout the entire engine much quicker than a car ran 100mi a day down the interstate. The soccer car grocery getter needs more oil changes than the Interstate freeway runner.
Why has many parts:
1) Never reaching full operating temperature means fuel and water vapor in the crankcase never burn off.
2) Each time you start the car cold it runs richer to maintain a smooth idle and that extra fuel is not only deposited into the crankcase oil but also into the intake when the car is shut off.
3) Each time you turn the engine off, combustion gasses must go somewhere and SOME of the intake and exhaust valves are open. Those combustion gasses, unburned fuel, and to some extent oil vapor deposit on the valves, and intake plenum up to the throttle body. Not to mention the EGR gasses which are now in the intake all attach as a film. Over years this accumulation adds up creating a physical layer of deposits. The intake valve being cooled by fresh air coming in is the prime candidate for deposits.
4) Offsetting this build up process can be as simple as trading cars with others in your life who freeway commute and OPEN the engine up for sustained higher RPM use when fully warmed up. High velocity through the intake, combustion chamber, and exhaust, slowly removes deposits.
You see this when people stomp on the throttle and the grey cloud of ash pores out the pipes freeing the vehicle of loose deposits that accumulate during idle time and putting around.
Add fuel cleaners at least 3x a year. Especially before winter freeze sets in to reduce the chance of moisture in the fuel system freezing and leaving you stranded.
FWIW I use Techron black bottle 3x a year in everything that burns fuel.
Bottom line is they need to reach full operating temperature AND be opened up occasionally! Grocery getters need more frequent OC than Interstate cars even tho they travel half the miles.
JM2C!
How you use the car matters!
City cars doing short 15" trips and idling more than being ran WOT will accumulate deposits in both intake and exhaust tracks as well throughout the entire engine much quicker than a car ran 100mi a day down the interstate. The soccer car grocery getter needs more oil changes than the Interstate freeway runner.
Why has many parts:
1) Never reaching full operating temperature means fuel and water vapor in the crankcase never burn off.
2) Each time you start the car cold it runs richer to maintain a smooth idle and that extra fuel is not only deposited into the crankcase oil but also into the intake when the car is shut off.
3) Each time you turn the engine off, combustion gasses must go somewhere and SOME of the intake and exhaust valves are open. Those combustion gasses, unburned fuel, and to some extent oil vapor deposit on the valves, and intake plenum up to the throttle body. Not to mention the EGR gasses which are now in the intake all attach as a film. Over years this accumulation adds up creating a physical layer of deposits. The intake valve being cooled by fresh air coming in is the prime candidate for deposits.
4) Offsetting this build up process can be as simple as trading cars with others in your life who freeway commute and OPEN the engine up for sustained higher RPM use when fully warmed up. High velocity through the intake, combustion chamber, and exhaust, slowly removes deposits.
You see this when people stomp on the throttle and the grey cloud of ash pores out the pipes freeing the vehicle of loose deposits that accumulate during idle time and putting around.
Add fuel cleaners at least 3x a year. Especially before winter freeze sets in to reduce the chance of moisture in the fuel system freezing and leaving you stranded.
FWIW I use Techron black bottle 3x a year in everything that burns fuel.
Bottom line is they need to reach full operating temperature AND be opened up occasionally! Grocery getters need more frequent OC than Interstate cars even tho they travel half the miles.
JM2C!
1. Fuel aromatics do not play like they used to, you can no longer burn off fuels dilution by driving on long periods of time, short of 8-9 hour straight highway drives.
2. Every issue you have described is really a ring seal in the combustion chamber rather than an actual inherent flaw in engine design or tune. This is 100% on the oil, nothing else.
3. Stomping on cards will not reduce or remove deposits, UNLESS, you have very very aggressive fuel cleaners or you are running ethanol in the engine.
08-17-17, 09:08 AM
#21
We'll have to agree to disagree on a few topics.
Yes, oil quality matters.
Our environment has moisture. Everytime the engine cools down moisture accumulates. Fully warming the engine to sustained operating temperature can and does burn off moisture and unburned fuel and to a lesser extent bypass gasses that blow past the rings.
How you use the vehicle matters. Two extremes are those hitting WOT for sustained periods vs someone lugging a stick shift about in high gear at low speeds. Lugging creates incredibly high cylinder pressures which induce blow by past the rings. The same reason many small displacement boosted engines tend to use oil and need a catch can. High cylinder pressures at low RPM induce piston rock unseating the rings allowing blow by to occur.
Again, higher port velocities from high RPM use can remove loose debris from all surfaces. Agreed, attached films, deposits, carbon will not be removed by air flow alone. Cycle back to vehicle use. Vehicles that idle a lot and do lots of low RPM city stop and go will have increased build up compared to an engine at ran at sustained 2500 RPM for example...
Yes, oil quality matters.
Our environment has moisture. Everytime the engine cools down moisture accumulates. Fully warming the engine to sustained operating temperature can and does burn off moisture and unburned fuel and to a lesser extent bypass gasses that blow past the rings.
How you use the vehicle matters. Two extremes are those hitting WOT for sustained periods vs someone lugging a stick shift about in high gear at low speeds. Lugging creates incredibly high cylinder pressures which induce blow by past the rings. The same reason many small displacement boosted engines tend to use oil and need a catch can. High cylinder pressures at low RPM induce piston rock unseating the rings allowing blow by to occur.
Again, higher port velocities from high RPM use can remove loose debris from all surfaces. Agreed, attached films, deposits, carbon will not be removed by air flow alone. Cycle back to vehicle use. Vehicles that idle a lot and do lots of low RPM city stop and go will have increased build up compared to an engine at ran at sustained 2500 RPM for example...
08-17-17, 09:27 AM
#22
Here is an article you can read by a GM guy. However he fails to address the importance of the oil.
http://thechronicleherald.ca/wheelsn...rect-injection
http://thechronicleherald.ca/wheelsn...rect-injection
08-17-17, 11:30 AM
#23
We'll have to agree to disagree on a few topics.
Yes, oil quality matters.
Our environment has moisture. Everytime the engine cools down moisture accumulates. Fully warming the engine to sustained operating temperature can and does burn off moisture and unburned fuel and to a lesser extent bypass gasses that blow past the rings.
How you use the vehicle matters. Two extremes are those hitting WOT for sustained periods vs someone lugging a stick shift about in high gear at low speeds. Lugging creates incredibly high cylinder pressures which induce blow by past the rings. The same reason many small displacement boosted engines tend to use oil and need a catch can. High cylinder pressures at low RPM induce piston rock unseating the rings allowing blow by to occur.
Again, higher port velocities from high RPM use can remove loose debris from all surfaces. Agreed, attached films, deposits, carbon will not be removed by air flow alone. Cycle back to vehicle use. Vehicles that idle a lot and do lots of low RPM city stop and go will have increased build up compared to an engine at ran at sustained 2500 RPM for example...
Yes, oil quality matters.
Our environment has moisture. Everytime the engine cools down moisture accumulates. Fully warming the engine to sustained operating temperature can and does burn off moisture and unburned fuel and to a lesser extent bypass gasses that blow past the rings.
How you use the vehicle matters. Two extremes are those hitting WOT for sustained periods vs someone lugging a stick shift about in high gear at low speeds. Lugging creates incredibly high cylinder pressures which induce blow by past the rings. The same reason many small displacement boosted engines tend to use oil and need a catch can. High cylinder pressures at low RPM induce piston rock unseating the rings allowing blow by to occur.
Again, higher port velocities from high RPM use can remove loose debris from all surfaces. Agreed, attached films, deposits, carbon will not be removed by air flow alone. Cycle back to vehicle use. Vehicles that idle a lot and do lots of low RPM city stop and go will have increased build up compared to an engine at ran at sustained 2500 RPM for example...
What you're not addressing is something called ring seal. I city drive my RC F and my fuels dilution is 1.2% for 5K. I see plenty of RC F's that do more highway, longer drives, etc that have FD in the 3% range. Address the ring seal issues and you'll never have blow by AKA fuels dilution issues. Ring seal is an oil issue and rarely a mechanical design issue. But most of us are taught oil is oil like the latest article on R&T.
FI/NA applications(super/turbo) don't require catch can's if the oil is providing proper ring seal. Catch cans will reduce amount of EGR deposits but doesn't address the issue and help but a minimal amount. I've proven this on many vehicles.
While use does play a significant factor, if you have a proper oil selection + fuel + air filter + oil filter + right additives, you can idle and drive "rough"(city driving) and not have any issues.
In terms of oil, you need UOA to determine what oil works best. Telling you to use one oil or the other is baseless short of having done many UOA and understanding thing from a different perspective, that being said, get a UOA and make a determination from there.
08-17-17, 12:24 PM
#24
^^^^Thanks for that information. It's great you have such a grasp on all of this. I, on the other hand, am a driver of a DI powered car. What goes on inside the motor and the oil/fuel contamination and EGR mechanisms and stuff are beyond my desire to spend countless hours trying to understand. I have another life. All I'm trying to ascertain is of there is a particular oil type, I should avoid or a particular oil-type that is better given that we all know the susceptibility of the IS250 engine to get carbon build-up. I'm not looking to cure it necessarily, but slow it down if there is a way. If a certain type of oil will help slow it down, I'll use that. If you can't answer that, then I'll just use whatever Lexus says/uses and hope they know what they're doing. I doubt they get a UOA on every car that comes in for an oil change so I guess they have generally chosen an oil that suits the majority of drivers of their cars. I just thought you might have some kind of rule of thumb for us novices.
08-17-17, 03:44 PM
#25
Sure, I'll address this the best I can. Have you ever called a shop and asked for them to tell you what's wrong with your car? They usually tell you to bring it in right? Even after you told them everything you knew. Problem is, you have no idea what's happening in your engine. You could be having build up from a multitude of conditions. Certain oils work for certain issues but it doesn't mean they cover them all. Now here's the problem, if I tell you go use X, and your issue worsens or remains because that oil didn't address it, there's reputation damage, etc and I'm not one who goes about things just guessing. I don't expect my carpenter to do UOA and I certainly don't remodel kitchens, so I understand you want an easy answer.
Lexus doesn't know what they're doing and the few internally that do, can't do anything about it. Someone for the largest CAT dealer in South Africa once asked me, "so if you know so much, how come you don't work at CAT and CAT hasn't fixed the issue." My answer was simple, these companies make much more money in SERVICE and PARTS, do you reAlly think they want your equipment to last for a long time?
No, they need to make money and to those that will claim the OEM will never do them wrong, all I have to say is look at VW, BMW, MB, Porsche, Audi, GM/Chevy, RAM, Chrysler, Jeep. They had no problem cheating us out on their diesel engines.
In short, you could use every 5,000 miles a bottle of Chevron Fuel Systems Cleaner and any high mileage/extended drain performance, etc, oil at Wal-Mart, AZ, etc and hope your issue slows down or if you want your issue to stop and increase power & fuel economy, consider getting a UOA. You can easily remedy what's happening for a few dollars compared to what you will eventually spend on an intake cleaning. I hope that's a decent answer that gives you my perspective as an oil analyst.
Lexus doesn't know what they're doing and the few internally that do, can't do anything about it. Someone for the largest CAT dealer in South Africa once asked me, "so if you know so much, how come you don't work at CAT and CAT hasn't fixed the issue." My answer was simple, these companies make much more money in SERVICE and PARTS, do you reAlly think they want your equipment to last for a long time?
No, they need to make money and to those that will claim the OEM will never do them wrong, all I have to say is look at VW, BMW, MB, Porsche, Audi, GM/Chevy, RAM, Chrysler, Jeep. They had no problem cheating us out on their diesel engines.
In short, you could use every 5,000 miles a bottle of Chevron Fuel Systems Cleaner and any high mileage/extended drain performance, etc, oil at Wal-Mart, AZ, etc and hope your issue slows down or if you want your issue to stop and increase power & fuel economy, consider getting a UOA. You can easily remedy what's happening for a few dollars compared to what you will eventually spend on an intake cleaning. I hope that's a decent answer that gives you my perspective as an oil analyst.
The following users liked this post:
leoferus (08-18-17)
08-18-17, 05:12 AM
#28
Lou, thank you. I'm sorry I asked a question that was already answered. I need to stop reading the forums after work. Many Toyota power plants have no EGR. It is simulated or unnecessary.
Anyways, I looked through the available documents regarding rough idle, carbon build up, and oil consumption. Here's what I found:
Some 2006 2010 model year IS 250 vehicles may exhibit one or more of the following conditions: • MIL ON DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306. • Runs rough after coming to a stop with the engine at operating temperature. • Runs rough with engine misfires present after a cold soak startup. Follow the procedures in this bulletin to address these conditions.
- The top end cleaner used: GM - General Motors Vehicle Care Upper Engine and Fuel Injector Cleaner GM# 88861802.
- The cleaner is poured into each cylinder and allowed to soak piston and rings.
Some 2006 – 2010 model year IS 250 and IS 250C vehicles may exhibit one or more of the following conditions: • MIL “ON” DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306. • Intermittently runs rough after coming to a stop with the engine at operating temperature. • Intermittently runs rough with engine misfires present after a cold soak startup. • Engine oil consumption exceeding 1 quart in 1,200 miles. The pistons and piston ring set have been updated. Follow the procedures in this bulletin to address these conditions.
- The cylinder head and valves are to be thoroughly cleaned.
- Pistons and rings replaced.
So, if you compare the two procedures, it seems that the valve contamination is a symptom of a ring problem. It might be possible to mitigate the carbon buildup issue by use of cleaners, carbon dilution, etc but if your vehicle's engine suffer from this condition it is a mechanical issue that will plague it until the pistons and rings have been replaced.
Anyways, I looked through the available documents regarding rough idle, carbon build up, and oil consumption. Here's what I found:
Some 2006 2010 model year IS 250 vehicles may exhibit one or more of the following conditions: • MIL ON DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306. • Runs rough after coming to a stop with the engine at operating temperature. • Runs rough with engine misfires present after a cold soak startup. Follow the procedures in this bulletin to address these conditions.
- The top end cleaner used: GM - General Motors Vehicle Care Upper Engine and Fuel Injector Cleaner GM# 88861802.
- The cleaner is poured into each cylinder and allowed to soak piston and rings.
Some 2006 – 2010 model year IS 250 and IS 250C vehicles may exhibit one or more of the following conditions: • MIL “ON” DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306. • Intermittently runs rough after coming to a stop with the engine at operating temperature. • Intermittently runs rough with engine misfires present after a cold soak startup. • Engine oil consumption exceeding 1 quart in 1,200 miles. The pistons and piston ring set have been updated. Follow the procedures in this bulletin to address these conditions.
- The cylinder head and valves are to be thoroughly cleaned.
- Pistons and rings replaced.
So, if you compare the two procedures, it seems that the valve contamination is a symptom of a ring problem. It might be possible to mitigate the carbon buildup issue by use of cleaners, carbon dilution, etc but if your vehicle's engine suffer from this condition it is a mechanical issue that will plague it until the pistons and rings have been replaced.
08-18-17, 05:52 AM
#29
Well, I'm just about due for my next 5k oil change. I'll get them to save me some and get the UOA done. Not sure how to interpret them, but hopefully someone here can help. The car has less than 20k on it and I doubt it has much if any carbon build up now. That is why I'm trying to find the best way to slow it.
08-18-17, 07:37 AM
#30
[QUOTE=leoferus;9957686]Lou, thank you. I'm sorry I asked a question that was already answered. I need to stop reading the forums after work. Many Toyota power plants have no EGR. It is simulated or unnecessary.
Anyways, I looked through the available documents regarding rough idle, carbon build up, and oil consumption. Here's what I found:
Some 2006 2010 model year IS 250 vehicles may exhibit one or more of the following conditions: • MIL ON DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306. • Runs rough after coming to a stop with the engine at operating temperature. • Runs rough with engine misfires present after a cold soak startup. Follow the procedures in this bulletin to address these conditions.
- The top end cleaner used: GM - General Motors Vehicle Care Upper Engine and Fuel Injector Cleaner GM# 88861802.
- The cleaner is poured into each cylinder and allowed to soak piston and rings.%3
Anyways, I looked through the available documents regarding rough idle, carbon build up, and oil consumption. Here's what I found:
Some 2006 2010 model year IS 250 vehicles may exhibit one or more of the following conditions: • MIL ON DTC P0300, P0301, P0302, P0303, P0304, P0305, and/or P0306. • Runs rough after coming to a stop with the engine at operating temperature. • Runs rough with engine misfires present after a cold soak startup. Follow the procedures in this bulletin to address these conditions.
- The top end cleaner used: GM - General Motors Vehicle Care Upper Engine and Fuel Injector Cleaner GM# 88861802.
- The cleaner is poured into each cylinder and allowed to soak piston and rings.%3
Last edited by danielTRLK; 08-18-17 at 07:44 AM.