JATLIFE

Hey guys (and gals), I read a ton about the carbon build up issue on the 250s in the thread here, but it seems like the majority of the problems occurred from 30K-70K. Mine ran flawlessly until close to 100K, when it would have the rough idle on startup... then it would occasionally do it at stop lights. I never thought much of it. It would happen once or twice a week, sometimes never. Around 100K is when I got my sparkplugs changed, and my mileage seemed to get worse... so, the MPG loss combined with the idling problem had me worried that the sparkplugs weren't done "right" (as you can tell I'm not very tech savvy WRT cars).

So about 6 months ago, I was exiting the freeway and at the light my car did the idle thing while stopped, the light goes green and as I'm turning my car is stuck at like 5K, wont shift, and all the engine lights and VSC lights come on. I go to the nearest light, turn it off, then turn it back on. The car seems to run fine, but I got the sparkplugs done immediately after. Ever since, I very rarely have any shakiness at idle, maybe once every month.

Soooooo... my car has 150K... what should I do, if anything? I use the Chevron fuel injector cleaner, get synthetic oil changes every 10K, use 87 octane ever since I bought the car brand new (yeah, I know some people are totally against this). Should I just ride it out or this a sign that I got lucky? Keep up with status quo? Increase the fuel injector cleaner (I pour the bottle in every 3-6 months) and/or up to 91 octane? I drive a ton of miles (25K a year), I'm at 150K, Car has been perfect for me other than the water pump going bad... and this. Thoughts? Any input would be greatly appreciated.

I don't want to dump it, and definitely don't want to pay thousands of dollars to fix it down the road. I have some mods (black 19" MRR GT1 deep dish, blacked out grill surround, HID lights/fogs, debadged, red-outs, lowered, blah blah blah) but I won't get anything close to what I think it's worth, since it has 150K miles as well... anyway, any thoughts? I don't know whether the 150K miles means I got one of the lucky ones (if there is such a thing) or is the Grim Reaper knocking down the door? You'd assume since it the issue has been happening far less I'm in better shape, but who knows.

Oh, and sometimes when I start it up it has this weird noise upon startup coming from the engine. Not all the time. Normal?

Sorry for all the words. Appreciate your response.

GiantsFan

iTrader: (9)

1) USE 91 OCTANE!!! It says so right in the manual. I can't seem to understand why people choose to cheap out on .20 cents a gallon.

2) Drive the crap out of your car. I was told by a Lexus tech that they go out on the freeway and REDLINE your car to test for the carbon issue (They try and get the car to throw a code). He says go out and hit the rev limiter and it'll burn the carbon right off. Not my words - Im just repeating what I was told by a certain tech.

A popular option for cleaning out the buildup is using seafoam, or getting a top end cleaning done at the dealer.

Hope this helps

rookieIS

iTrader: (8)

1. shouldn't you have been ALREADY using 91octane since day 1?

2. fuel injector cleaner does nothing to help carbon built-up

my advice, unless you have extended warranty, do a top engine cleanup

rookieIS

iTrader: (8)

you beat me to it.. haha

JATLIFE

Re: using 91, Car and Driver did a study a while back an basically said that unless your car is pinging, you can go down to 87 and all you lose is a few HP. I usually fill up at Shell. Sounds like C&D was full of crap?

Re: redlining. This car is always being driven relatively hard. WOT or close nearly every time I drive.

JATLIFE

Sounds like I ought to switch to 91 and talk to someone at the dealer about the top engine cleaning.

GiantsFan

iTrader: (9)

^I don't mean WOT. I was specially told to put it in S, and HIT redline for a good 5-10 seconds.

Yes, Its scary lol.

Again, not saying for you to do it, I'm just telling you what I was told. So don't hold me liable if you do something wrong to your car

Your best bet would be to do the top engine cleaning/seafoam. But also note - the issue will return, you will have to do it again in the future.

kumquatism

iTrader: (10)

Lexus, the car manufacturer, states that premium fuel is required, not recommended, for this specific car. I'd go for that over some car magazine's general observation.

RDIS250AWD

iTrader: (7)

+1
Also says use premium only inside the fuel door

Bichon

Just as an aside, it's about .31 cents a gallon more in NJ. http://fuelgaugereport.opisnet.com/sbsavg.html

In fact, oddly enough, it look to be about .30 cents more in every state where gas is cheap, but only .20 cents more in those where gas is expensive. Strange.

That said, I always put premium in my car.

JATLIFE

Just to close this out: my tech had me bring it in multiple times. It was misfiring at first but wasn't within the range they needed it to be for the "fix"... he said bring it again and it will surely be within the range... next time, it wasnt... brought in again after I happened to me at a light, and they couldnt recreate it... happened a few times after, they said they cant recreate it and now its not misfiring at all and runs like a car with 7,000 milles according to their tests not a car with 157K... called lexus corporate and said what do I do here? it's doing it from time to time, but dealer cant recreate, what if my engine craps out a day after the extended warranty expires, they said they would put a note in the system that if my engine went out due to this at any point in the life of the car, they would replace it for me... nice. Oh, and the car hasn't had any problems in 6 months or so. Odd.

NickTomsyc

12 to 1 compression .... use 91+ octane, always.

I buy premium at Sam's Club / Costco - the premium here is the same price as regular everywhere else.

bob4256

iTrader: (17)

USE PREMIUM GAS.

I could care less what study car and driver (or any other website/magazine) does, it says to use premium on the gas cap. The engineers who built this car would know more about the car than anyone.

teefar

I agree with what everyone else is saying about high octane. Also a redline a day keeps the carbons away. Just like I did with my Mazda RX8. Redline it as you're coming off the exit ramp on the interstate.

NYKnick101

Are you still using 87 or did you go up to 91? Ive noticed that there is more than a year difference in this thread! 87 wont hurt your engine but it would cause that every now and then. Try not to mix octane levels too much.

and if your engine craps out, then your gonna have to either sell the car or get a new engine. which the 250 engines can be bought for like 1500 bucks or so