Side note, about two months after I got the parts from Yam6 and this whole thing was in my rearview mirroer, I got a bill from FedEx on behalf of the US Gov't. Part of importing this stuff from Europe is paying the tariff(?) on it...I think it was about $20...so budget for that!
New owner and already screeching Master Cylinder :( (2 Viewers)
- Thread starter riffman12
- Start date
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- Thread starter
- #22
hey guys wanted to update the thread here:
I got my pump and accumulator combo from Yam6 and had my local Toyota mechanic replace it. All said and done it cost me about $1300 including the price of the part.
Car has been perfect since. No screeching, no alarms. Been starting it in the morning cold etc. and it's been fine
Then out of nowhere, this morning I turn the car on and the exact same symptoms are back. Screeching, All the warning lights, Loud beeping. I was so mad.
I turned off the car and pumped the brakes until all the pressure was gone and the pedal went to the floor. Then I restarted the car and the pressure immediately built up in the pedal and the screeching stopped. 5-10 seconds later the alarm turned off along with all the warning lights.
I drove around doing some errands. Probably 50 miles of stop and go and freeway driving, not a single issue since.
i really hope this was a fluke? I remember reading another member who this happened to then he went ~3 years with no issues.
Anyone know why it would have done this out of the blue and fixed itself after a full pump cycle?
I got my pump and accumulator combo from Yam6 and had my local Toyota mechanic replace it. All said and done it cost me about $1300 including the price of the part.
Car has been perfect since. No screeching, no alarms. Been starting it in the morning cold etc. and it's been fine
Then out of nowhere, this morning I turn the car on and the exact same symptoms are back. Screeching, All the warning lights, Loud beeping. I was so mad.
I turned off the car and pumped the brakes until all the pressure was gone and the pedal went to the floor. Then I restarted the car and the pressure immediately built up in the pedal and the screeching stopped. 5-10 seconds later the alarm turned off along with all the warning lights.
I drove around doing some errands. Probably 50 miles of stop and go and freeway driving, not a single issue since.
i really hope this was a fluke? I remember reading another member who this happened to then he went ~3 years with no issues.
Anyone know why it would have done this out of the blue and fixed itself after a full pump cycle?
uHu
Bridgeburner
Mr Riff, was all the brake fluid changed, including the active ABS bleeding, when the master was changed? I'm thinking there could be some impurities or humidity in the old fluid. Not easy to get out without a very thorough flushing.
- Thread starter
- #25
My mechanic assured me that the system is fully flushed with new fluid.
Done. No sign of leaks.
Thanks for the help guys.
It happened again this morning. This time it took 2 rounds of engine off pumping, turning car on to stop the squeeling. After that it was fine for the rest of the day. My mechanic suggested I go and cycle the ABS a few times on a gravel road. I did this and will try starting it in the morning and see if it's still doing it.
Squealing (alarm) with absent of dash lights could be a booster accumulator not centered. But you've reported dash lights in past post so I assume same now.
With no real issue with braking other than it's shutting down ABS (dash lights on) and engine running fine.
It seems to leave two possibilities:
Water getting onto electricals inside cabin near foot wheel from rain, snow or car wash. This could set off alarms and shut down ABS. But pumping pedal to evacuate booster would not normally stop alarm in that event. Unless by some fluke your pumping pedal 40 to 80 times, is moving enough air in foot wheel along with vibration of action, too dry off moisture from wiring/junction box.
Or
Defective new master, in which sensor is signaling reservoir is low.
With no real issue with braking other than it's shutting down ABS (dash lights on) and engine running fine.
It seems to leave two possibilities:
Water getting onto electricals inside cabin near foot wheel from rain, snow or car wash. This could set off alarms and shut down ABS. But pumping pedal to evacuate booster would not normally stop alarm in that event. Unless by some fluke your pumping pedal 40 to 80 times, is moving enough air in foot wheel along with vibration of action, too dry off moisture from wiring/junction box.
Or
Defective new master, in which sensor is signaling reservoir is low.
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uHu
Bridgeburner
That probably means that he did not exchange all the fluid. Changing the fluid include activating the ABS - the procedure is in the FSM.
Not saying that this is the cause of your problem, but it should have been done.
It does sound like a problem with pump, motor, accumulator/valve.
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- Thread starter
- #28
So if he didn't activate the ABS properly, would it be causing this screeching noise? I checked with him and he says it's all new fluid that was flushed through.
I tend to think this sounds more mechanical than fluid related. Booster and accumulator are brand new, I believe the MC is original. No fluid level drop that I can see
Does anyone have more info on the accumulator alignment issue? The problem is pretty consistent now. Usually goes like this
1. Get in car, start the engine
2. screeching starts, every 3 seconds or so
3. Mess with brake pedal a bit and it quiets it then it starts again
4. turn off car, pump pedal 30+ times until the pedal goes completely soft / to the floor
5. Start car with foot on the brake. Feel it come up quickly as the pressure builds
5. Drive away with no issues. It seems to be taking more and more on/off cycles every day now to get it to behave
If I let the car idle with the screeching, it will do it for about 15-20 seconds total, then suddenly there will be a "thud" through the pedal and the warning lights will come on
I'm so confused
- Thread starter
- #29
ok well going to try and bleed all 4 corners again this weekend. Not sure if that could be causing my screeching noises, but I suppose it's worth a shot before dropping $2k+ on a new MC assembly.
Anyone know the cheapest place to get the full MC assembly?
Anyone know the cheapest place to get the full MC assembly?
- Thread starter
- #30
Ok another update.
I bled the booster this weekend by pumping the pedal with key off. Waited until the accumulator emptied.
Then i bled all 4 corners and got some bubbles out of the right rear .
Then set the brake fluid level with the accumulator empty.
Now the noise seems to have gone away. However, the mornings have been warmer and the cold used to make it worse.
Is there a chance air in the system was causing the screeching? Or is this likely to return as soon as its cold again?
I bled the booster this weekend by pumping the pedal with key off. Waited until the accumulator emptied.
Then i bled all 4 corners and got some bubbles out of the right rear .
Then set the brake fluid level with the accumulator empty.
Now the noise seems to have gone away. However, the mornings have been warmer and the cold used to make it worse.
Is there a chance air in the system was causing the screeching? Or is this likely to return as soon as its cold again?
I had that squealing only once last month never again tho was a cold start no dash lights tho lasted for 2 seconds and then went off by itself.
How's it going @riffman12 ? - Are you still having issues?
Seems we could have numerous causes of "Squealing"
- alam indicating low fluid. Top fluid, watch for indication of leak.
- Air in the Master assembly (master, ABS unit, booster pump, accumulator). Bleed, Activate ABS/booster w/SST electronically or manually, bleed. Note it is possible that manually activating ABS may not be sufficient.
- Accumulator not centered properly, which may transfer a squealing sound. Adjust.
- Water entry into electronics of side cowling junction box. (I've had this active alarm when E brake on) Fix leak.
- ABS/booster pump connection fault. Replace wire harness assembly between ABS & booster pump motor.
- Booster pump failing. Replace.
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- Thread starter
- #37
I actually bit the bullet and replaced the whole MC assembly. Over 1000 miles since and no issues. Even had it parked overnight in 7 degree snow.
Sucks but it was worth it for me to know it was good to go for another 200k
So how is your Master Cylinder from ebay holding up?
I recently woke up to this issue after leaving my truck outside on a cold, rainy night. I guess its been kind of the same issues as riffman but differs in that the lights flicker on and off rather than staying on. The other oddity is that the squealing will stop if I take a circular freeway exit ramp at decent speed. The issue occurred less than 12 hours after replacing the battery. Does replacing the battery with pressure in the system damage the pump?
