Help! Weird noise

[jonathanfedel]

I just bought a scion tc a few weeks ago. Recently it has been making a grinding noise or slipping noise only when i first take off or let out the clutch. It only does it when i start the vehicle and take off, after that it never does it while driving. I have 2007 5 speed. Any ideas what it could be? I checked the cv joints they seem to be fine.

[DatsunScion]

i had a car once that did a similar thing (it was more of a rattle though...). Ended up being a loose splash shield. It would rattle only on take off.

[jonathanfedel]

Really, well the weird thing is that it only does it when i start the car and drive off. all the other times when i take off i doesnt do it.. I think im going to take the belt off and jack the front up and let it run through a take off that should let me know if it is the belt or acessory pullys, or something to do with the clutch

[navylife59]

May just be your clutch. It may be a bad throwout bearing or the input shaft spline does not have any grease on it and is galled. Other possibilities with the prescribed symptoms might be just a worn-out clutch. How many miles on the car? How does the transmission shift? Being that the noise does not happen except in first and on start would preclude the serpentine belt, CV joints, or transmission fluid level. With the motor off, do you feel any grinding when engaging/disengaging the clutch?

More on the clutch read here; http://www.club-tc.com/forums/tc-kno...omponents.html

[jonathanfedel]

No the clutch seems fine, with the motor off and it never does it only let the clutch out for the first time when driving never happens again. The tranny fluid is new i just flushed it i though that might have been the problem. The clutch has been inspected and seems to be fine. For some reason i think its the powersteering, but its not showing and symtoms of that being the problem.

[navylife59]

Could be the throwout bearing. The input shaft could be in need of grease but you should feel it with the motor off if it is dry and galled. The throwout bearing would only give you indications with the engine running as the input shaft spins with the flywheel unless the clutch is disengaged. It would be noticeable during engine starts and heard most in 1st gear. After that, road and engine noise can mask it out. If the clutch was visually inspected thru the plastic cover on the lower bell housing and it precluded any premature wear, damaged springs, or cracked flywheel, then the throwout bearing steps forward in the list.

The starter bendix could possibly be not retracting fully causing the gear teeth to either be completely or partially engaged into the flywheel ring gear. It might correct itself ones the flywheel gets past a certain RPM or over a certain amount of time. This would only be an plausible explanation if, once the noise stops, that it does not return until the motor is shut down and restarted. Starter can be easily removed for inspection, as well as, the flywheel ring gear would have chipped teeth or evidence of the bendix riding the gear teeth.

[jonathanfedel]

but see i can sit there and let it idle for ever and it will not do it, if it was the starter on the flywheel it would do it when it idles because the fly wheel always spins. Anyone think it could be the powersteering or belt slipping when i first take off then it catches and doesn't slip again.

[navylife59]

Sounds like a throwout bearing that is running dry on grease. Would explain why it goes away after a little while. The serpentine belt could be slipping till it warms up but it would not change with depressing the clutch. When you first start up the motor you can rev the motor and should hear it squeal if it is the belt. Turning the wheel may or may not produce a squeal on the belt.

[jonathanfedel]

how would i grease the throwout bearing, or do i have to pull apart the transmission.

[navylife59]

Unfortunately, yes you have to drop the tranny to get to it. It rides on the input shaft. It is hard to diagnose a problem like that without being there. If the noise is grinding, then it can't be the serpentine belt. That would only make a squeal.

[jonathanfedel]

no way to shoot grease at it from the inspection point or clutch fork.

[jonathanfedel]

ok its not a grinding noise more a slipping noise. and i have figured out that it is coming from the passenger side.

[navylife59]

That sounds more like the serpentine belt then. Does it change at all with the A/C on or off? Has your water temps been abnormally higher lately? Are you loosing any radiator fluid? Does the sound ever change when turning the steering wheel?

[jonathanfedel]

it only does it when i take off and its not transmission because when i pop it out and coast with the clutch back in it will do it, I will upload a video could my tensioner be bad. Maybe it only slips till it grabs, but a part of me thinks the starter engages and gets stuck so when i drive away it whines out till it pops back. i have been driving it for 4k like this and it has no mechanical problems.