As many of you know, some forum users (including myself) are noticing starter grind after cold start (and after every start in bad cases)
I spend a lot of my free time to investigate the cause (with some misleading conclusions along the way, my thread here https://www.fitfreak.net/forums/1st-...art-noise.html). I also bought a used starter from high mileage Fit to use it as guinea pig, but still had no definite answer.
So yesterday "by an accident" I've found an old (2008) thread on Acura RSX forum posted by sxy2003, which pretty much describes an issue:
"I have had a grind issue on start up at cold temperatures. Right after the engine starts, I heard a loud screeching sound similar to turning the key for too long. This issue only occurred when the car cooled down for a long time (like starting it first thing in the morning).
So I replaced the starter and decided to disassemble the old starter to attempt to figure out why it grinds in clod temperatures. In short, I think it's pretty clear that it's the solenoid...
...Solenoid seems to be working well. But as you can see, there is some wear on the sides of the piston, showing something is not right.
I put it in the freezer for an hour to duplicate the cold start condition. [I've done it too with my junk yard starter but it worked fine! - Dr.J]
After trying to compress/release it a few times, I noticed it produced screeching [rather old mattress spring squeaking noise - Dr.J], as well as hesitation to pull back. So I believe I found the problem here...
Note that when starting a car, the engine relies on the starter to immediately pull the gear away and if the solenoid hesitates at all, it would in fact produce screeching noise forcing the gear back into the starter housing [via spiral splines - Dr.J].
https://forums.clubrsx.com/showthread.php?t=611726


Another situation which I initially believed was the case, is the noise produced by dried out grease of the planetary gear set (Commonly reported on VW cars)
After some audio clip analyses I created the following list which should help to identify source of the noise.

Planetary gear:

Can be reproduced on or off the car;

High tone (sounds more like screech or squeal);

Can be produced even if engine does not start

Is generated by planetary gear rattle as starter armature coasts to stop

Caused by bad lubricant or starter bushing wear

Starter drive:

Can be produced only if engine starts (spins faster than starter pinion)

Lower tone (grinds or whines)

Is generated when pinion gear is disengaged from the flexplate (flywheel)

Caused by “sticking” pinion gear, which in turn is caused by:

a) step wear on the starter output shaft

b) sticky solenoid plunger (weak spring, burrs, hardened rubber boot cracked plunger bore lining)

c) sticky one way clutch

d) bend or contaminated spiral spines on the starter output shaft

I added audio files of noise made by planetary gear set [ crank,start,pause, screech]on VW Jetta and sticking starter pinion gear on 2008 Honda fit [Crank, start, screech]
PS I'll ask moderator to move this thread into the stickies

 

Good report, doctor J. Thank you.

 

Awesome! What's the best fix?

 

The right fix is to replace solenoid, however since solenoid is sold for more than rebuilt starter, for most people it means reman starter
I will try to take solenoid apart and see what causes it to stick, it does not doing it on my used starter though

 

Thanks for doing all this legwork and compiling this report!