Fixing dead/dying NES carts?

One of my NES carts (Castlevania) locks up sometimes randomly...sometimes around Frankensteins stage, and the only time it got past that part without crashing it...it crashed.

Ditch it and buy a new copy or is there a way to revive it?

 

Pencil eraser on the contacts.

-hl718

 

Scotchbrite pad/steel wool, for those tough oxidations (...don't overdo it), if it's really an issue with the contacts.

If it's ROM-related... it's done for.
My copy of Super C died one day. Nothing can bring it back, that I can see.

 

I'm not sure it's in the contacts , i mean the game lassts up until the last level.

 

There's nothing dying about it, the first revision of Castlevania apparently has bugs that cause the game to crash later on.

 

source?

 

http://nesdev.parodius.com/bbs/viewtopic.php?t=4461

It's that or metastability because without SRAM or something retaining the game's state (well, resetting could do it temporarily) there's nothing that could break your specific cart with malformed data from non-initialization/poor handling. And having a few bits just flip in your ROM is pretty out of the question.

 

oh wow. it's at the stage they mention too. Is there a way to tell which NES cart is the original and which is the revision?

 

Yeah, on the back of the revised cart there should be something like "REV A".