Lexus IS250 4GR-FSE Engine Carbon Build-up (merged threads)
10-16-12, 02:23 PM
#1172
I got some pretty bad shaking the other day at a light, and I have the updated pistons too. I drive about 50 miles a day when I do drive to go into the office and have noticed this issue for a while now. This sucks 
I keep having them check it all the time at the dealer when i'm there, but since it hasn't thrown a code since the piston update there's nothing that can be done - Lexus rejects further repairs. Since there's nothing new beyond the updated pistons, I'm assuming a misfire with new pistons would probably just be fixed by doing a top engine clean. Unless you can convince them to give you a new block.
I keep having them check it all the time at the dealer when i'm there, but since it hasn't thrown a code since the piston update there's nothing that can be done - Lexus rejects further repairs. Since there's nothing new beyond the updated pistons, I'm assuming a misfire with new pistons would probably just be fixed by doing a top engine clean. Unless you can convince them to give you a new block.
10-16-12, 03:23 PM
#1173
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Hi all,
I have an IS350 and have noticed a lot of the same symptoms you guys with the 250s have complained about...
Rough idling, almost dying at stop lights, engine not feeling smooth, etc.
I know this may not be an option for everybody, but what I've found to eliminate this problem is using ethanol free gasoline.
I've been using ethanol free gas for the past several months and immediately noticed a smoother idle, and the car seemed to run better and better each tank for several tanks.
Two tanks ago, I filled up with the general ethanol enhanced gasoline and the rough idle almost immediately returned. This Saturday I filled up again with the real gasoline and it is running correctly again.
I hope this information benefits somebody.
Just remember, normally gasoline and alcohol don't mix. Some chemical is added to keep the alcohol suspended in the gas. That chemical is what I believe to be the issue with direct injection engines. And yes I realize the is350 has the port injectors as well...
I have an IS350 and have noticed a lot of the same symptoms you guys with the 250s have complained about...
Rough idling, almost dying at stop lights, engine not feeling smooth, etc.
I know this may not be an option for everybody, but what I've found to eliminate this problem is using ethanol free gasoline.
I've been using ethanol free gas for the past several months and immediately noticed a smoother idle, and the car seemed to run better and better each tank for several tanks.
Two tanks ago, I filled up with the general ethanol enhanced gasoline and the rough idle almost immediately returned. This Saturday I filled up again with the real gasoline and it is running correctly again.
I hope this information benefits somebody.
Just remember, normally gasoline and alcohol don't mix. Some chemical is added to keep the alcohol suspended in the gas. That chemical is what I believe to be the issue with direct injection engines. And yes I realize the is350 has the port injectors as well...
11-10-12, 11:33 AM
#1175
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Just took my 2007 is250 with 110K to the dealer for service. I have had the rough idle after an aggressive stop about 7 or 8 times since the car was new. Dealer is upgrading the pistons and rings at no charge...sweet deal.
11-10-12, 10:21 PM
#1177
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it sounds like MAYBE (just maybe) lexus tinkered with the ecu/computer to maybe NOT throw codes. total speculation here. would anyone happen to know?
I got some pretty bad shaking the other day at a light, and I have the updated pistons too. I drive about 50 miles a day when I do drive to go into the office and have noticed this issue for a while now. This sucks I keep having them check it all the time at the dealer when i'm there, but since it hasn't thrown a code since the piston update there's nothing that can be done - Lexus rejects further repairs. Since there's nothing new beyond the updated pistons, I'm assuming a misfire with new pistons would probably just be fixed by doing a top engine clean. Unless you can convince them to give you a new block.
I keep having them check it all the time at the dealer when i'm there, but since it hasn't thrown a code since the piston update there's nothing that can be done - Lexus rejects further repairs. Since there's nothing new beyond the updated pistons, I'm assuming a misfire with new pistons would probably just be fixed by doing a top engine clean. Unless you can convince them to give you a new block.
11-12-12, 07:25 AM
#1178
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My big problem is that Lexus KNOWS that they aren't fixing the problem. Pistons and rings cannot fix the issue. They need to run the 7th injector more often to clean the intake valves. But they can't because of the EPA preventing them from changing the fuel delivery maps. It's total B.S., but that's where we're at.
12-16-13, 04:32 PM
#1179
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BG Products - Gasoline Direct Injection Kit
I just got the BG Products - Gasoline Direct Injection Kit.
Products: 208, 271, 272,4068
208: Throttle Body and Intake Cleaner
271: Gasoline Direct Injection Cleaner Part 1
272: Gasoline Direct Injection Cleaner Part 2
4068: 44K
I found a mom and pop BMW shop that would do the top engine clean up with the kit and change the spark plugs (which will be removed in the process) for $350.00
Instructions are included with the kit. It seems pretty easy, I wish I could do it myself, but I'll settle for oil changes only.
I got the kit from ebay.
http://www.ebay.com/itm/251385274933...84.m1439.l2649
Products: 208, 271, 272,4068
208: Throttle Body and Intake Cleaner
271: Gasoline Direct Injection Cleaner Part 1
272: Gasoline Direct Injection Cleaner Part 2
4068: 44K
I found a mom and pop BMW shop that would do the top engine clean up with the kit and change the spark plugs (which will be removed in the process) for $350.00
Instructions are included with the kit. It seems pretty easy, I wish I could do it myself, but I'll settle for oil changes only.
I got the kit from ebay.
http://www.ebay.com/itm/251385274933...84.m1439.l2649
12-23-13, 07:08 AM
#1180
Driver School Candidate
I've written back quite a few pages a method for solving this issue involving a small circuit box that tricks the temp sensor on startup to use the 7th injector every time you start for 30 seconds. I haven't done that as I don't have any issues with my IS250. Lexus could do this with a quick reprogram of a few extra lines of code, but they won't for whatever reason.
01-19-14, 02:24 PM
#1183
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I have a few questions.
1st: Has there been any early 2010 is250 with this carbon build up problem?
2nd: Has there been any 6 speed manuals with this problem?
3rd: concerning question 2. If so, how can you tell if you have the carbon issue?
I have a early model 2010 is250 manual with 45k
Thanks
1st: Has there been any early 2010 is250 with this carbon build up problem?
2nd: Has there been any 6 speed manuals with this problem?
3rd: concerning question 2. If so, how can you tell if you have the carbon issue?
I have a early model 2010 is250 manual with 45k
Thanks
Last edited by vinceiscoo; 01-19-14 at 02:32 PM.
01-20-14, 01:25 PM
#1184
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The reason why 6MT owners never notice any issues is because the idle speed is probably regulated to be a little higher.
It's a V6... It's not a naturally balanced engine and the lower the RPMs the closer you get to a resonant frequency. I think the software needs to be tweaked for a higher idle RPM in drive (when lights and A/C are off). Even at idle, there is some drag on the engine from the transmission / torque converter. On 6MT cars, depressing the clutch or shifting into Netural is the same as neutral in the 6AT cars.... and the idle is perfectly smooth.
It's a V6... It's not a naturally balanced engine and the lower the RPMs the closer you get to a resonant frequency. I think the software needs to be tweaked for a higher idle RPM in drive (when lights and A/C are off). Even at idle, there is some drag on the engine from the transmission / torque converter. On 6MT cars, depressing the clutch or shifting into Netural is the same as neutral in the 6AT cars.... and the idle is perfectly smooth.
I'm really worried about this carbon issue but haven't seen anyone with manual receiving the tsb service. Obviously all 2006-2010 is250 are having this issue.
