is250gurl

they found nothing wrong with my car after three tests looking for codes again so they did a throttle body cleaning and i will pick it up this afternoon after talking to their head tech again. they also looked at the motor mounts and they are fine too. they did this after i told them repeatedly that the loaner they give me never idle rough or vibrate and my car does.

bob4256

iTrader: (17)

Alright so Im going to take the lazy route and not go though 64 pages and just ask. What is the general cause of this issue? Ive heard others mention that to prevent it, you should drive it hard (WOT) ocassionally. Is this true?

is250gurl

nope it comes down to bad engine design!

Kurtz

iTrader: (1)

The general cause is that direct injection vehicles do not inject fuel above the valves. So that carbon buildup on those valves never gets cleaned away by fuel like it does on port injection vehicles.

Nothing you can do will prevent this from happening.

Several things you can do may make it take longer to happen though (occasional WOT, running proper octane fuel, the piston/ring TSIB to reduce blowby, etc)


Once it DOES happen you'll need a top engine cleaning (few hundred bucks) and then it'll be gone again until it builds back up.

Again this isn't a Lexus-specific problem it's a problem with older designs of DI engines across many manufactures

http://www.autoobserver.com/2011/06/...-adopters.html

bob4256

iTrader: (17)

Does the piston/ring TSIB apply for all 2IS's or only certain years? Im not really that informed about TSIB's so I aplogize in advance

Kurtz

iTrader: (1)

All 250s made before a certain date/VIN number. (range ends somewhere among 2010 models I think?)

350s don't have the problem because they use direct and port injection.

But bear in mind it's a TSIB, not a recall, so you have to actually be experiencing the problem and be under warranty for the dealer to fix it free.

KillaIS250

iTrader: (1)

Another update on my situation...

Went to go check out my car today since I was in the area. They did discover misfire codes, and after ~1,000 miles of driving on the new pistons they opened everything up again and what do you know....carbon build up!!!! I am amazed, the service dept is amazed. The shop foreman took a compression test as well as photographs to send off to Lexus Corporate. I am now waiting on a response from them on what to do. It seems the foreman is requesting a replacement of the entire short block as the possible solution to corporate. I am not the only 250 either, when I asked my SA, there are 2 other's with 250's in a similar situation - facing problems after having the pistons replaced. If they are replacing my entire block, i'm gonna see If i can ask for a goodwill extension of the powertrain warranty from Lexus corporate. Otherwise.....

How she looks right now:

gemini1

iTrader: (7)

At least your temporary putting miles on another car then yours! LOL

I took mine to Westminster lexus and they caught the misfire codes and ordered the parts.
Drop my 250 off sometime next week or after for the carbon issue.

J3ffrey

The replaced my block.. without even doing the pistons first.

zen

iTrader: (6)

I found the TSIB related info from pdf file.
It seems during the replacement for piston/ring under TSIB, the shop should also inspect the block to see if there are any scratches on the block wall or damages. If there are scrtaches/damages then it needs to get replace under the TSIB.

Also, does anyone perform the intake valve clean on carbon buildup by themselves ?

mojeko

stephin. mine too i have 40,000 miles on it. i just got my car 2 days ago. they change my piston and ring. i still have vibration on it every time i stop on red light, but it's not the same last time. last time every time i stop on red light my engine almost died and shake. since they change my piston. it drives brand new "for now". i don't know what would be happened on next 40,000 miles again ? i hope it won't build up carbon again. because i didn't get the extended warranty.

KillaIS250

iTrader: (1)

Carbon build up is pretty much a guarantee because of the design of the engine. It's really a matter of "when" and not "if"

stanjohn12

It would be great if someone could put up a DIY on how to clean these valves for the high mileage member's.

mickificki

Exactly what I've been wishing for. I'm not mechanically inclined but can follow write ups ok. Anyone here done a cleanup themselves?

[QUOTE=stanjohn12;7274972]It would be great if someone could put up a DIY on how to clean these valves for the high mileage member's.[/QUOTE]

KillaIS250

iTrader: (1)

A few members have just seafoamed the car to burn off the Carbon.