by "way2blu does a rev update" (way2blu)
Published 09/23/2017 at 18:11
by "way2blu does a rev update" (way2blu)
Published 09/23/2017 at 18:11
Tags: Toyota MR2
STARS: 0
Under moderate to heavy braking, I get a metallic scraping sound. It’s high-pitched and lags about a half-second behind when I press or release the brakes. Been getting worse today so I’ve stopped by a coffee shop to consult Oppo.
As far as I can tell, the sound comes from the passenger-side wheel well when my windows are down, but it sounds like it’s coming from the engine bay if I have the windows up.
The sound is more grating than the eeeeeee that I used to hear before I got new front calipers and rotors. It definitely sounds like metal-on-metal, but I can’t place what’s scraping. A visual inspection of each wheel has left me puzzled, as everything seems to be in place.
The sound’s lag is also concerning. I can hear the sound start about a half-second after I first apply the brakes, and then it persists for a half-second even after I completely release the pedal.
Are there any quick tests or inspections I can conduct in order to see what’s wrong? Any advice is appreciated, as I’m hoping to keep the vehicle healthy enough for autocross in a few weeks.
"Urambo Tauro" (urambotauro)
09/23/2017 at 18:14, STARS: 3
Did your inspection include both sides of the rotor?
"Straightsix9904" (Straightsix9904)
09/23/2017 at 18:25, STARS: 3
Have you pulled the wheel? It sounds like a brake pad, inspect both sides. If the pads are abnormally worn for the amount of time you have had them you have a stuck cylinder in the brake caliper and it needs rebuilt or replaced.
"Steve in Manhattan" (blogenfreude01)
09/23/2017 at 18:28, STARS: 0
Stuck caliper? Also, MR2? Rear discs, or drums?
"way2blu does a rev update" (way2blu)
09/23/2017 at 18:32, STARS: 0
I’m not sure I have the equipment to check the other side, but that’s a very good point. I had to drive to another coffee shop and I’ve noticed that the sound is the same pitch and intensity regardless of what speed I’m braking from. Even < 10 mph, it sounds the same.
I’ll see what I can do to take a look at the other side too. I have access to another car today so I’ll just drive that one to work later instead.
"way2blu does a rev update" (way2blu)
09/23/2017 at 18:33, STARS: 0
That could be it. Might explain the lag in the sound too if the cylinder isn’t engaging and disengaging as quickly as the others.
"way2blu does a rev update" (way2blu)
09/23/2017 at 18:35, STARS: 0
Discs all around. I think the stuck caliper hypothesis is pretty valid, the last brake service I had only fully replaced the front brakes.
"Steve in Manhattan" (blogenfreude01)
09/23/2017 at 18:42, STARS: 0
Also maybe a partially or fully collapsed brake line - think those are non-metallic.
"RacinBob" (racinbob)
09/23/2017 at 19:12, STARS: 0
I think you have a rear pad that has gone to the backing pad. Assuming a single cyl caliper, I think the pad is hanging up on the bracket and doesn’t move freely. Once it gets stuck (usually due to corrosion) It just rides against the rotor and wears quickly to the backing plate.
For whatever reason, if you are in country with winters, it just seems to be a common event for rear and not front calipers as it has happened on about every car I have had. Anyway, put in new pads, make sure every thing is free and my bet is problem solved.
I would not condemn the brake line or caliper until I tried to just replace the pad. You may have a different problem but I doubt it.
BTW, what car are we talking about?
"RacinBob" (racinbob)
09/23/2017 at 19:15, STARS: 0
Here’s my most recent repair, 80,000 mile rear rotor and pads from a chevy uplander.
"DC3 LS, will be perpetually replacing cars until the end of time" (dc3ls-)
09/23/2017 at 20:51, STARS: 0
Sure it’s not the wear indicator for the pads?
"pip bip - choose Corrour" (hhgttg69)
09/23/2017 at 20:54, STARS: 0
stone between rotor and backing plate?