jvah1980

I was driving on the highway (2006 IS250 w/ 134k miles) when suddenly Check VSC and flashing Check Engine light came on, and there was significant power loss. I pulled to the side of the road, shut the car down. The car engine was running very rough, the RPM's were high despite a slow speed. Gave it a sec and turned it back on and everything is now fine for another 100+ miles.

I've saw a few other posts of similar situations. I'm about 10k miles overdue for spark plugs (getting them done next month). I realize this could be anything, (Carbon Build-up, spark plug, ignition coil, etc), but with no stored codes I could find from the incident where do I start? I guess spark plugs are a given, and maybe replace the 3 rear ignition coils at the same time to be on the safe side (considering the work in removing the plenum).

The car runs perfectly, no idling issues, or sputtering that so many people mention as a result of the carbon build-up. I do burn oil as mentioned in a previous post (about a quart every 1500 miles). Unfortunately, the incident has shaken my confidence in the car. There are more than few highways in NYC where it would be terrifying to lose power like that and not have any place to pull over.

videopho

It might very well be your alternator.
Similar issues but the car stranded me on the highway. Car needed to be towed to a nearest Toyota dealer.

Dallasguy1

I think these are the symptoms of carbon buildup and Lexus has a enhancement TIS available for this in which they'll rebuild your engine again with no charges on you. If I would be you I'll take it to the nearest dealer for diagnostics. It's 100$ worth spending.

jvah1980

Unfortunately it is my understanding that was a 9 year unlimited warranty which I'm now almost a full year beyond.

It would be a little easier if there was a stored code to pull. If it happens again anytime soon I will have to take it in. But it's almost a moot point. Paying for a rebuild is not an option. Might as well drive it until the engine blows.

jbuck55

I had same thing.......called dealer and he said that you must ALWAYS make sure that your gas cap is on very tight after each time you visit the pump. This has happened to me twice and both times I tightened the cap and drove about 15 miles and lights went out. Give it a shot..........you have nothing to lose.

jvah1980

thanks for the update!!

This did happen shortly after filling the tank and it crossed my mind maybe it was just bad gas or something. I'll keep an eye on this.

Thanks.

Bichon

I know you are just trying to help, jbuck55, but what you experienced is not the same thing at all. You had a solid check engine light, and if you had plugged in a scan tool you would have had seen a P044X or P045X series diagnostic trouble code (probably P0441), indicating that the evaporative emissions system leak test which runs during each drive cycle failed. The original poster had a flashing check engine light (which indicates a misfire) and the car went into "limp mode"; no way that a loose gas cap would cause that.

jbuck55

Thanks for the correction..............I did miss that part about "flashing" check engine light.

Mrfix

Well one way to figure out what happened is to read the codes. The VSC has nothing to do with your problem. Your ECU went into safe mode and the VSC is disabled to relieve strain on your engine and this will happen anytime there is a problem with the engine.

I would bet that it is a carbon problem and the reason I say this is because you burn a lot of oil (should have installed a catch can). At some point it will affect performance and you will notice it at higher speeds than at lower speeds or idle. The only other thing I would guess is fuel pressure. Your fuel pump might be going. But again I will bet the carbon build up is at the point where it is affecting performance at higher speeds.

A code scanner is like $20 bucks off of Amazon and TorquePro is $5 bucks on the play store. It's the number one thing everyone should have. Why not know what is wrong with your vehicle when something breaks.