Hey all. I've got a 2003 civic LX, it has developed an issue with a severe stutter while going up slight grades @ 1800-2000rpm and 40-45 mph. RPMs don't drop, car just shudders. If I let off the gas and accelerate (move out of that rpm range) it goes away. Doesn't happen every time, but most of the time in that range. Doesn't happen at any other speeds or RPMs. Is this anything simple, or most likely a big fix?