Hello!
I have an 2009 is350 with 431 miles on it. The car is brand new and during does 431 miles, I slammed the gas about 4 times for 5 seconds each. Is this a no-no for the break in period or is it alright to give it a gas every quite often? Also do you think I damaged the car by flooring it with such little miles on the car? Thanks!

 

define "slammed the gas" like full throttle punching it? our engines are built pretty tough but nonetheless you should be babying your car! its got under 500 miles hahaha

 

newer cars these days dont really need to be broken in. there's a website online that teaches you break in your car by WOT(wide open throttle) to make your car faster overall for the life of the car.

 

who gives a **** about break in. i just drive the car as i would normally whether it has 0 miles or 50k miles.

 

I've learned that when there's a break-in period it's cause the motor was freshly rebuilt and needs a tune. But the car is straight from the factory already tuned so IMO if you want to be safe wait 1000miles but if not smash that btch!

 

i bought my car from lexus of cerritos.. as soon as i drove it off the lot, i made that left turn onto the 605 south and floored it

 

What is more important is if the engine was warmed up.

 

Don't worry about it. Read the manual for break-in recommendations.

 

Drive it like you stole it, but don't bring it up to redline for the first 1k miles methinks just to play it safe. The manual's break-in recommendations are just that, recommendations; newer engines do not need to be broken in like back in the seventies. I remember my mom telling me that when she bought her first new car in 1982 the dealership told her to drive the car under 40 mph so that the paint would cure well. We all know nowadays that's pure bull****.

 

i've always found this phrase interesting... if you steal a car are you gonna pretend your dale jr. at daytona??? no~ you're gonna try to blend in with the sheep, to not attract attention... well thats what the 'smart' criminal does... *cough* not saying that i think of how to get away with stealing a car, umm... just what i heard from frien... wait... i dont have friends like that.... umm... isn't today such lovely weather?

 

I would have used another term, but I would have been labelled a white supremacist.

 

I'd be surprised if you didn't punch it once in a while. I don't think anyone I know with an IS 350 who completely babied the car for the first 1000 miles. I did a few WOTs during break in as well.

You're not going to break this car, trust me. It's a very low maintenance sports sedan. Keep your tire pressures up (check once a month) and do the simple maintenance every whatever miles (I take it to the stealership for completeness but that's just me) and you will be just fine.

Like others have said, many guides will recommend that you run through the gears at varying throttles (including full WOT) for truly proper break in. That's what I did.

1/4 throttle, 1/2 throttle, full throttle from 0.

The only thing I did was I tried to make sure I didn't stay at the same speed for too long.

You should try to vary your speed. That's why city driving may be useful during break in. On the highway, I sometimes slowed to 55 and then went 1/2 throttle to 85 or 90.

I just tried to do a variety of things, seems to have worked great.

 

Oh one thing I did to "gauge" my level of babying the car versus hard accelerations --> I used my tank average MPG as a gauge. I tried ti keep it at 18-20 MPG

You know with 300 HP cars like this it's very possible to go as low as 10 or 11 MPG if you drive REALLY REALLY aggressively...I probably would not do that during break in.

I know some people in IS-Fs have gone as low as 6 MPG on track days.

so keep it above 18 MPG I guess. This is all very unscientific but it's a very very rough gauge I suppose.

Anyone who knows more please feel free to chime in/correct me, I just pulled this "MPG gauge test" out of my *** to be honest but it seems reasonable to me.

 

first day i got it, i let it run for 3 hours straight.

 

I can easily get a respectable 25 mpg on the highway in the F on those long trips to Toronto.