This applies to any vehicle, but since this is the only auto forum I’m on (80 series), figured I would throw it out here. Google didn’t turn up anything I didn’t already know, and nothing to help my issue.
Done lots of brake jobs, familiar with the system, etc, but feeling stumped here. Hoping I’m an idiot and it’s right under my nose. Recently picked up a 5VZ ‘98 from a competent mechanic friend. He did brakes and a thorough bleed, but it needed a new booster which he hadn’t yet installed. I did that yesterday, adjusted the little plunger for the master so the brakes behaved properly. Took it for a spin, felt proper, thought I was done. Easy. But today, it’s acting up. I believe the booster is functioning properly, but now my reservoir is acting like I have a leak somewhere. Pedal pumps up nice and firm with the engine off, no fluid loss. With engine on, thus booster doing its job, pedal doesn’t do much until it gets close to the floor, and I lose fluid from the res with each pump. Can’t find any leaks at the four corners, master and nearby lines are dry, booster is dry, nothing else visible. I’ve gone through enough fluid to expect to see something somewhere, whether on the vehicle or the ground, but that’s not the case.
Before the new booster, I had no symptoms of a leak at all - no fluid loss from res. All I can deduce is that when the (now functioning) booster is doing its job when the engine is running, it’s pushing fluid out somewhere new, but I can’t find anything for the life of me. If it’s a leak, it’s hiding like a mofo. Even with engine off and no booster, shouldn’t I still lose some fluid when I keep pumping? Please tell me I’m having a brain fart and missing something
Done lots of brake jobs, familiar with the system, etc, but feeling stumped here. Hoping I’m an idiot and it’s right under my nose. Recently picked up a 5VZ ‘98 from a competent mechanic friend. He did brakes and a thorough bleed, but it needed a new booster which he hadn’t yet installed. I did that yesterday, adjusted the little plunger for the master so the brakes behaved properly. Took it for a spin, felt proper, thought I was done. Easy. But today, it’s acting up. I believe the booster is functioning properly, but now my reservoir is acting like I have a leak somewhere. Pedal pumps up nice and firm with the engine off, no fluid loss. With engine on, thus booster doing its job, pedal doesn’t do much until it gets close to the floor, and I lose fluid from the res with each pump. Can’t find any leaks at the four corners, master and nearby lines are dry, booster is dry, nothing else visible. I’ve gone through enough fluid to expect to see something somewhere, whether on the vehicle or the ground, but that’s not the case.
Before the new booster, I had no symptoms of a leak at all - no fluid loss from res. All I can deduce is that when the (now functioning) booster is doing its job when the engine is running, it’s pushing fluid out somewhere new, but I can’t find anything for the life of me. If it’s a leak, it’s hiding like a mofo. Even with engine off and no booster, shouldn’t I still lose some fluid when I keep pumping? Please tell me I’m having a brain fart and missing something
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