View Poll Results: Have you experienced the Carbon buildup issue on the IS250?
Yes. I got the service done under warranty one or more times
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44
43.56%
No. Never had this issue. Car runs like a sewing machine.
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34
33.66%
Carbon buildup? What is that? Is Al Gore linked to this?
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23
22.77%
Voters: 101. You may not vote on this poll
IS250 Carbon buildup Poll
#17
Lexus Champion
Thread Starter
#18
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2. I experienced it for the first time probably around 48 to 50k.
#19
Lexus Test Driver
iTrader: (4)
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A/C off...It first happened at 30K Miles and I am now at 47K have not stalled nor gotten the tsib. I just WOT in the morning after the car is fully warmed up everyday.
It happens from time to time though...5000 miles...200 miles.. Its random. I was trying to calculate whether it happened every certain number of miles but nope...
It happens from time to time though...5000 miles...200 miles.. Its random. I was trying to calculate whether it happened every certain number of miles but nope...
#20
Lexus Champion
Thread Starter
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Wow one would think that if the carbon is causing the problem, it would keep doing it since the carbon is stuck in there. I think there is something else not the carbon causing the stall
#21
#24
Lexus Champion
Thread Starter
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Here is some more evidence that quicker oil changes might have a hand to play in this, although it is not indicated as such by the OP.
http://www.audizine.com/forum/showth...gathread/page2
Quote Originally Posted by BEM3 View Post
Here’s another data point. This is my first post and unfortunately it doesn’t have anything good to report…
Vehicle Make/Model: 2008 Audi A4 3.2L
Location: Seattle, Washington
Mileage/Date: 11,990 miles / 30 November 2009
Oil used: Unknown. Dealer Supplied
Oil Change Interval: Average every 2850 miles*
Fuel Used: Chevron Supreme Techron (91/92 octane) or Shell V-Power (91/92 octane)
How short/long are your trips on average: 6 to 30 miles
Reported rough idle when cold to the dealer. CEL was on. Did not notice any loss of power.
Dealer invoice states:
“Verified Customer Concern. Hooked up scan tool, found five random engine faults. P0300, P0301, P0302, P0303, and P0304 (random cylinder misfire, cylinder misfire 1-4). Followed TSB 2019948/3, added fuel additive and road tested vehicle for 60 miles sustaining high engine RPM. Allowed vehicle to sit for several hours to repeat cold start up. Hooked up scan tool and cold started vehicle, MVB 14 registered 8 faults (4 in cylinder 1, 2 in cylinder 2, and 2 in cylinder 3). Will open TAC ticket. **- (Tech 2751) opened TAC ticket. They said to check camshaft adjustment. Performed check through MVBS 90-96 and they are fine, there are no sticking adjusters. Removed intake manifold and found carbon build up on back of valves. TAC said to perform cleaning as stated in the TSB. Cleaned valves, removed spark plugs, blew out carbon chunks. Reassembled and test drove. Let sit outside overnight and started cold. There was no misfire on any cylinder. Performed oil service per TSB. Closed TAC ticket. Done.”
Note:
Vehicle purchased new with 49 miles / 27 September 2008
Engine (short block) replaced for cylinder wall scoring 6521 miles / 14 April 2009
*Oil change interval shorted by engine replacement
Drove the car from Seattle to San Francisco and back. It currently has over 15,000 miles on it and its starting to run rough when cold again. Thank goodness for warranty!
Here’s another data point. This is my first post and unfortunately it doesn’t have anything good to report…
Vehicle Make/Model: 2008 Audi A4 3.2L
Location: Seattle, Washington
Mileage/Date: 11,990 miles / 30 November 2009
Oil used: Unknown. Dealer Supplied
Oil Change Interval: Average every 2850 miles*
Fuel Used: Chevron Supreme Techron (91/92 octane) or Shell V-Power (91/92 octane)
How short/long are your trips on average: 6 to 30 miles
Reported rough idle when cold to the dealer. CEL was on. Did not notice any loss of power.
Dealer invoice states:
“Verified Customer Concern. Hooked up scan tool, found five random engine faults. P0300, P0301, P0302, P0303, and P0304 (random cylinder misfire, cylinder misfire 1-4). Followed TSB 2019948/3, added fuel additive and road tested vehicle for 60 miles sustaining high engine RPM. Allowed vehicle to sit for several hours to repeat cold start up. Hooked up scan tool and cold started vehicle, MVB 14 registered 8 faults (4 in cylinder 1, 2 in cylinder 2, and 2 in cylinder 3). Will open TAC ticket. **- (Tech 2751) opened TAC ticket. They said to check camshaft adjustment. Performed check through MVBS 90-96 and they are fine, there are no sticking adjusters. Removed intake manifold and found carbon build up on back of valves. TAC said to perform cleaning as stated in the TSB. Cleaned valves, removed spark plugs, blew out carbon chunks. Reassembled and test drove. Let sit outside overnight and started cold. There was no misfire on any cylinder. Performed oil service per TSB. Closed TAC ticket. Done.”
Note:
Vehicle purchased new with 49 miles / 27 September 2008
Engine (short block) replaced for cylinder wall scoring 6521 miles / 14 April 2009
*Oil change interval shorted by engine replacement
Drove the car from Seattle to San Francisco and back. It currently has over 15,000 miles on it and its starting to run rough when cold again. Thank goodness for warranty!
Vehicle Make/Model: 2008 Audi A4 3.2L
Location: Seattle, Washington
Mileage/Date: 18,082 miles / 01 April 2010
Oil used: Unknown. Dealer Supplied
Oil Change Interval: Average every 4520 miles*
Fuel Used: Chevron Supreme Techron (91/92 octane) or Shell V-Power (91/92 octane)
How short/long are your trips on average: 6 to 30 miles
*Oil change interval shorted by engine replacement and valve cleaning
Issue: “Client states CEL is on and vehicle has a rough idle when started cold”
Dealer invoice states: “Verified Check Engine Light was on, performed guided fault finding, found fault P0301 Cylinder 1 misfire detected, P0303 Cylinder 3 misfire detected, both were at cold start, checked for TSB’s, found TSB2020645/4 for ECM update, updated software, suggest leaving car overnight to cold start and verify repair retested AM ok.
Less than a week later…
Vehicle Make/Model: 2008 Audi A4 3.2L
Location: Seattle, Washington
Mileage/Date: 18,255 miles / 09 April 2010
Oil used: Unknown. Dealer Supplied
Oil Change Interval: Average every 4520 miles*
Fuel Used: Chevron Supreme Techron (91/92 octane) or Shell V-Power (91/92 octane)
How short/long are your trips on average: 6 to 30 miles
*Oil change interval shorted by engine replacement and valve cleaning
Issue: “Client states the Check Engine Light is on. Please verify and advise (rough when cold)
Location: Seattle, Washington
Mileage/Date: 18,082 miles / 01 April 2010
Oil used: Unknown. Dealer Supplied
Oil Change Interval: Average every 4520 miles*
Fuel Used: Chevron Supreme Techron (91/92 octane) or Shell V-Power (91/92 octane)
How short/long are your trips on average: 6 to 30 miles
*Oil change interval shorted by engine replacement and valve cleaning
Issue: “Client states CEL is on and vehicle has a rough idle when started cold”
Dealer invoice states: “Verified Check Engine Light was on, performed guided fault finding, found fault P0301 Cylinder 1 misfire detected, P0303 Cylinder 3 misfire detected, both were at cold start, checked for TSB’s, found TSB2020645/4 for ECM update, updated software, suggest leaving car overnight to cold start and verify repair retested AM ok.
Less than a week later…
Vehicle Make/Model: 2008 Audi A4 3.2L
Location: Seattle, Washington
Mileage/Date: 18,255 miles / 09 April 2010
Oil used: Unknown. Dealer Supplied
Oil Change Interval: Average every 4520 miles*
Fuel Used: Chevron Supreme Techron (91/92 octane) or Shell V-Power (91/92 octane)
How short/long are your trips on average: 6 to 30 miles
*Oil change interval shorted by engine replacement and valve cleaning
Issue: “Client states the Check Engine Light is on. Please verify and advise (rough when cold)
http://www.audizine.com/forum/showth...gathread/page2
#25
Driver School Candidate
Join Date: Sep 2012
Location: CA
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I have 109K miles and just learned about this issue. I having the shop do all the additives and hope that does the trick. Problem started off with rough idle and moved to getting the VSC light and others coming on. I hope this works as I'm not going to pay for such an expensive recurring problem. I did not expect this from Lexus!
#27
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I have 109K miles and just learned about this issue. I having the shop do all the additives and hope that does the trick. Problem started off with rough idle and moved to getting the VSC light and others coming on. I hope this works as I'm not going to pay for such an expensive recurring problem. I did not expect this from Lexus!
https://www.clublexus.com/forums/is-...-up-csp-2.html
#30
Lead Lap
iTrader: (11)
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Ok, I can't believe I'm reading this... I'm an engine freak and will say this.... Doing later oil changes will harm the engine for sure!! One main cause is compression loss. Dirty oil will cause the piston rims to burn down 800% faster causing carbon buildup and loss of power and gas milage.. Your cars oil is like your body's blood. When the oil gets brown it is from gas and microscopic metal pieces that are too small to be filtered out.. My cousin has 2 is350's both have around the same milage being well over 300,000. One was always maintained with moble 1 synthetic 5W 30, every 3K on the dot. The car has only lost around 5-9 psi on each cylinder for compression, and still running strong. The other is350 had oil changes around 8,500-9,500 miles also with synthetic lost around 40 psi on compression on all 6 cylinders and still was getting carbon buildup. Both cars were driven the same way. Cheap oil can damage valve seals causing the engine to burn oil. Bad gas and clogged injectors also cause problems in the engine bay. I have 7 cars in total and do my oil changes every 3000 miles and I NEVER had any problem with carbon or other problems..
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firestart9 (08-05-23)