newgsman

iTrader: (4)

I went to start my car this morning after not driving it for about three days and nothing happened when I pushed the start button. So I double checked to make sure it was in park, had my foot on the brake and again the car wouldn't start. The only thing that would happen is it would engage the accessories same as if I pushed the start button without having my foot on the brake pedal. I did notice that the brake pedal felt unusually hard as in, it would not depress more than a few millimeters. I decided to push on the brake pedal with considerable amount of force which resulted in it depressing maybe a few millimeters more. Then when I pushed the start button the car started up and the braked pedal sank a few inches like normal when the car first starts up. Everything was normal after this. Made a few pit stops on the way to work and the brakes felt fine and the car started perfectly normally.

Anyone experience anything similar. I have had the car for only a week and a half. It's a 2012 isf.

itsmike177

iTrader: (3)

Had the exact same issue as described. Dealer replaced the brake vacuum check valve and fixed.

PatrickISF

I've experienced this too, twice. I haven't experienced it for awhile though.

justfme

My F is not my DD so it will sit for 4-5 days without being started. This happens EVERY time I start it for the first time after it has been sitting.

lobuxracer

iTrader: (2)

I've never had this issue even letting the car sit for a week. It should not happen, and replacing the check valve is exactly the right thing to do. The check valve is letting air in so the vacuum goes away and you have no power assist before starting. It should easily hold for a couple of weeks without starting the engine.

newgsman

iTrader: (4)

Thanks for the replies guys.

So only one replacement of the vacuum check valve?? (presumably under warrant?)

Anyone else?

lobuxracer

iTrader: (2)

Definitely warranty. Part number is 44730-28030. It is used on a pretty wide range of Toyotas, the IS-F and the ES. Around $30 from Internet Lexus retailers.

caveman

i definitely have this issue. brake pedal is stiff as a brick after two days of not driving.

need to get it fixed under warranty next time i'm in.

ISRocker

iTrader: (1)

I have this same problem. I think it started happening after my brakes were replaced. I took the car back to the dealer and the dealer couldn't replicate the issue. There doesn't seem to be a pattern as to when it happens. But it seems to be happening more frequently, about 3 times a week now. I have to take my car into the dealer soon. Hopefully the info here will help them locate the issue!

Defratos

I regularly get this, didn't realize it was an issue and brakes as well as brake oil level are fine.

Are you guys sure this is a problem? if it was a problem with valve then wouldn't it affect the brakes while driving normally?

I'm 100% sure even if I took it to the stealers they'll have no idea what I was talking about....as usual!

MisterSkiz

iTrader: (2)

I've been meaning to replace my brake booster check valve...been noticing that I get a weird rattling sound when I am on the brakes at a stop light...

ISRocker

iTrader: (1)

Dealer had my car for 3 days. Could not replicate the issue so they didn't replace anything...

newgsman

iTrader: (4)

Took my car in to have this checked out yesterday. I told them the pedal stiffens up after about two or three days. They gave me a loaner (plain jane no options IS250) and said they will let the car sit for a day or two to see if they can recreate the situation. This afternoon they called me to tell me it's the brake booster. They have one on order and will be replacing it (under warranty) when it arrives. they said I can continue to drive the car as it is.

Wondering if I should tell them to make sure it's not just the vacuum check valve or should I just let them go ahead and change the whole booster? I suppose a new booster would be nice although it is very rare that these things fail over the reasonable life of a car. The flip side is that I hope they don't mess something else up when changing the booster. Any comments?

streetx

iTrader: (4)

Is the check valve a difficult part to replace? Rather just fix this myself since it's only a 30 dollar part

I8ABMR

LOL I just went through this with my SA. The car is fine. What happens is when you get in the car you dont realize but you keep stomping on the brake pedal to get situated. When you press the pedal a few times the pressure gets pretty high and then you need to push really hard to get it to the point where it will start. LOL He said he had 2 people with IS350 and one ES this month with the same complaint. He even watched the people get in and start the car and pointed out to them how many times they stomp on the pedal getting situated and putting their belt on. Mine did this after my last track day when I got home and I was cleaning the interior. I went to start it and the pedal was rock hard,. I even freaked out and took it in right away. My car was fine
. I think they are replacing it because they can,

If you dont believe me stomp on your brake pedal 4 times before you start it . $50 says it feels like a rock when you go to start it