NWIS250AWD

07 IS250awd. Around 34k, always run synthetic, premium fuel etc. On 2 occasions the car would stumble, vibrate bad, then limited to 40 mph.

First time taken to dealer they reset the computer, kept overnight, road tested with no more problems.

2 months later same thing. Occured late one night on the way home. No more problems in the morning on the way to the dealer.

The dealer after contacting Toyota has now taken the heads off to clean and rebuild per a known issue that is getting more widespread.

This has to due with carbon build up due to the design of the heads is what was relayed.

If this happens at 34k, will it happen again in another 30k out of warranty due to the design of the engine?

If this is the case then it may be best to sell the vehicle and go with one that has a better engine design?

I have owned many many toyotas for there bulletproof and long lasting, no problem design. This is why I chose the Lexus for the wife. Now I am not so sure.

Help me keep my faith in Lexus and the engine design of the IS250 otherwise it may be looking into 08 G35x.

Hate this crap.

shrka

man that sounds serious. sorry to hear that. if you could, you should change it to another car...esp if your wife drives it. that's my 2cents.

greg0723

sorry to hear that. maybe that could be one of the few cars that are built not to last. nothing is 100% there is always a lemon

Kurtz

iTrader: (1)

If it makes ya feel any better the engine warranty is 70k miles

sandwiches

iTrader: (1)

If you're under warranty, let the dealer fix and it and don't sweat about engineering problems. If they cannot fix it to your expectations, then switch to another car.

NWIS250AWD

It seams the problem is more widespread than I thought. I will be discussing it more in depth with the dealership. Very glad for the 70k warranty but this should not occur on a toyota let alone a lexus. If it takes 30 to 40k to recreate the scenario then were out of warranty with a 5k repair bill to rebuil the top end.

Toyota is aware of the issue and I will see what service bulletins are issued. This is not a few cars or limited to 07's.

Evil Teo

iTrader: (13)

when i had my car it happen before 30k. not sure why but it was like after 10k it happen. that was when i had my is250awd. are u running on fully synthetic motor oil? cuz i noticed after i made the switch this had occurred not sure if this is causing it but worth lookin into.

NWIS250AWD

Running factory oil - filters since new.

06isDriver

that happened ONCE to me while I've been monkeying with my intake. It cleared itself up the next day and I havent seen that particular error again. My car has 56k on it now and this happened at about 48k

is250gurl

wow this isn't what i want to hear about my is250! i've been complaining about the occasional studder i get from my car at idle every few months or more and they keep talking about carbon build up on the throttle body and a fuel injection cleaning. i find this hard to believe after only 42k on the car and only using premium gas since day 1. a clean & rebuild? you've got to be kidding me.

Gaugster

Interesting. I've got 40k+ miles and have never had the car go into limp mode.

2slow

iTrader: (5)

If it happens again with the same problem, the dealership will buy back your car. If they don't give them the number to BAR (Bureau of Automotive Repair) and ask " do you want to call or shall i." and they will tend to your needs.

Lemon law

Kurtz

iTrader: (1)

Given the OP isn't in California BAR will ask WTF he's calling them for.

His own state has a lemon law, but it's not relevant to his situation if this first began happening a couple months ago around 30-something thousand miles

http://www.atg.wa.gov/LemonLaw/General.aspx

NWIS250AWD

Got the car back tonight. I really wish all service writers had a minimum required 6 months as a grunt mechanic so they know how to answer someone with a mechanical background. The end result was as follows:

Carbon buildup within the combustion chamber which causes the valves to stick. This is a knows problem on both the 250's and 350's and it is widespread as the local dealer has cleaned a good amount (that is just one dealer) out of 3 within 70 miles.

When initially brought in they found 26 counts in EWMA 4 and failed misfire monitor. Misfire on cylinder 5. They created TAS case and attatched live data. TAS case number 100510018. Contacted DS322 which ok'd for top end cleaning.

They removed plenum, ignition coils and plugs.

Applied top end cleaning solution into the combustion chambers and let sit for 1.5 hours. Then reinstalled everything and changed oil and filter.

They state that this is the fix that Toyota uses. I do not see anything that was done that changes the design parameters to not repeat the problem in another 40k miles.

Lastly I was mistaken the vehicle has 44k not 34k as previously stated. Most of the vehicles comming in with the problem range from 34k to 50k.

Does this sway my from keeping the IS.... I will give it another couple oil changes and see if anything else occurs. I bought the car for the wife to have a very dependable vehicle. After almost stranding her twice in the last 2 months I am not amused and will start researching 08 G35X to see how they compare. I do know there engines are highly rated. Time will tell and for now the IS is behaving as it should.

Clay Easto

Did they say to use fuel system cleaners? I use Techron a few times a year, I wonder if that will help at all.

I am glad I bought the extended warranty. This type of crap never happened on my Acura.