Hello I have a 91 hatch dpfi stock minus exhaust and intake. I know when I start the car and let go of the clutch there seems to be a grinding sound. I'm pretty sure it's the throw out bearing. I'm a motor head but am a newbie with Hondas. When I accelerate it gets louder. Different from any car I've owned that had a bad throw out bearing. Just making sure I know what I'm talking about. Any and all help would be appreciated. Sorry for the newbie question.

 

add 2 more things it could be to the list
-front brake pad, easy to inspect, it may be to the indicator prong. Jack car up, use jackstands to support it, remove wheels, and look at how much meat is left on the pads.
-bearing for the trans, would be where the axle hooks in to it. The car may have been abused somehow, and the bearings can go out. I towed a uhaul trailer 2300 miles in my olds CRX Si, and the bearings of the trans eventually ate themselves. I replaced the trans, but then later decided the one with bearings went out shifted better, better syncros, so i got new bearings and fixed and swapped it again. When mine went out, I could look at the axle output of the trans and I saw metal shavings and spiraled steel coming out where the seal was...

 

Could be a lumpy pressure plate (the fingers where the throwout touches aren't laying even and flat) Could be the input bearing, could be the - well, damn near any bearing or anything spinning inside of the trans. some more info on the noise would be helpful - like what kind od grind, cruch, is it dependant on gear or does the noise change when you accelerate vs decellerate?

 

it only changes when accelerating ad silent when the clutch is pushed in.

 

Input shaft bearing

 

mine does this too on a b16a first gen with a s1 cable tranny. Is it the input shaft bearing?

 

i had a similar issue with my 90 CRX Si, turns out that it was the output shaft barring in the trans. i swapped trans' from another civic and regrettingly scrapped the Si trans. i should have fixed it and kept it.

even tho going to the civic dx trans i got gears that were a little longer, so highway cruising was a litte nicer at lover revs

 

No metal shavings no visible damage to axles. It sounds like a bad throw out bearing that's the only sound I can explain. Shifts great in between gears and is silent when clutch is pressed. Does not change with gears and higher speeds stay the same. Have no idea what a input shaft bearing is. Lol. Is it hard to replace? Thanks for the help guys.