Lexus IS250 4GR-FSE Engine Carbon Build-up (merged threads)
03-06-12, 01:56 PM
#768
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2006 IS's all get new springs, retainers, shims when/if the pistons are replaced. (sometimes valves) Newer IS's usually do not reqire replacement of anything other then the pistons/rings.
And when the heads are off the valves are cleaned/lapped.
03-06-12, 02:20 PM
#769
Drive the car in a lower gear on the freeway for 1.5 miles (keep it around 4-5.5k rpm), exit the freeway and come to a stop. If it is going to misfire, that will cause it. That test drive procedure is the one Lexus has us do on any IS with a misfire mutiple misfire code. During that drive cycle with the cars live data up on a tech-stream we do a misfire count. The number of misfires determines the repair performed. Some cars get new valves (or valves lapped), new pistons, new piston rings or a combination of the three.
03-06-12, 02:30 PM
#770
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That is just the test procedue that Lexus has us use. doing it yourself wont really help much unless you have a techstream or another way to capture live data to show misfire counts over the drive time. And even so the dealer needs to duplicate it with the techstream to send that data to Lexus.
Just take it to your dealer and tell them that the car feels like it is going to stall when you get off the freeway, They should know what to do from there.
And so you know, the best way to get taken care of is to tell the dealer the symptoms you have, don't go in there and tell them that you need LSB90823908423904823904823940. If you want a certian LSB performed, just look up the symptoms and tell them that.
Just take it to your dealer and tell them that the car feels like it is going to stall when you get off the freeway, They should know what to do from there.
And so you know, the best way to get taken care of is to tell the dealer the symptoms you have, don't go in there and tell them that you need LSB90823908423904823904823940. If you want a certian LSB performed, just look up the symptoms and tell them that.
03-06-12, 03:37 PM
#772
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"Guest states the car feels like it is going to stall when coming to a stop"
Not
"I want free pistons, perform LSB 098432342etc."
lol
03-06-12, 03:51 PM
#773
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Lexus has you lap the valves? That's sad. There's no quicker way to ruin a good valve job. Lapping kills flow at low lift.
03-06-12, 05:01 PM
#774
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03-08-12, 09:15 AM
#777
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Also, how have other manufacturers like VW and GM resolved the issue? It seems this is an inherent flaw of any DI system. Me thinks a lot of Focus and Elantra owners are in for a nasty surprise in a few years.
03-08-12, 11:13 AM
#778
So perhaps instead of every 20k miles it happens every 50k.
A couple hundred buck top engine clean would then buy you another 50k miles before it comes up again.
So it's not ideal, but it's not like the car will cost 10 grand to repair every 6 months or something.
(Disclaimer: those 20k and 50k numbers are total speculation on my part for sake of the example... could really be 30k and 100k or 15k and 30k... or anything else)
Yeah, others have had the same issue... Audi, VW, Hundai, and more... check this story about it:
http://www.autoobserver.com/2011/06/...-adopters.html
It mentions VW including in its 2002 patent the following:
Originally Posted by VW
Gasoline engines with direct injection of the fuel into the combustion chamber…suffer especially from the problem of the formation of carbon deposits…especially in the neck region of the intake valves
The article suggests that newer DI motors won't have these problems (or not nearly as bad anyway) due to design, material, and engineering changes.
03-09-12, 07:35 AM
#779
After that, I feel the engine runs very tight, barely making any "noise" as well as the throttle tip-in to be on the slow side, meaning I have to push the gas pedal (feels more resistance) down to get it moving, as opposed to a light touch to spin it up. Ever heard of anything like this?
03-09-12, 12:26 PM
#780
I read a lot about this carbon buildup issues and Lexus replaced the piston and ring on my 09 IS250 about 3 months ago. After replaced, I don't have the issue of stall when I come to a stop. I know it's not a permanent fix, but does anyone know if the Lexus extended warranty cover this work if I need to replace the piston/ring again in the future ?