car goes lean when braking

[Jiggalude]

When I brake hard, or several times in a row, the AFR gauge goes completely to the red. I'm assuming it's a boost leak. Wondering if there was a specific spot or a specific issue others have run into with this.

 

[Achelea]

On the back side of the intake manifold there is a hose going from the brake booster to the intake manifold. It's not long and it's pretty easy to spot. The brake booster is the big flat can shaped thing on the firewall.

 

[92AWDHX40]

Do a boost leak test to find your leaks if any, the red light, blinky light dont know about that.

 

[68442]

Keep in mind the injectors stop when you coast and brake. Was worried about this in my ecmlink log until I was told that is normal. A wiseman may confirm this.

 

[tips000]

yes the injectors do slow/ stop but IF you are having idle problems or stalling/ choking problems when stopping then i would for sure check the brake booster line and any other boost leaks.

 

[GIRman67]

yes it's totally normal. when you let off the throttle the computer detects no air going in so it shuts off or slows the injectors until about 1400RPM. I believe it was LiquidX that said that in a thread that was posted no more than a week ago.

 

[Jiggalude]

Yea I know that when you left off the throttle that the car goes lean. That's fine. My issue is that if I'm I sit and pump my brakes, I can make the car go completely lean. Off the charts lean on my wide band. I'm assuming it's a boost leak, I just didn't know if anyone had specific experience like this and maybe good give me a good source of it. I wonder if the brake booster or Master cylinder could be bad?