My 2002 Forester (MT) hesitates when I drive on or off the car-ferry.
Typically, the engine is warm when I line up for the ferry. After a 15-30 minute wait, the ferry arrives and I restart the engine to drive aboard at slow speed.
The car lurches/hesitates in 1st gear, most notably when I ease off or on the throttle. Sometimes the hesitation is so bad that I deal with it by coasting with the clutch depressed in 2nd gear, and just give a little forward acceleration every few seconds to keep the speed up.
The same hesitation happens when I drive off the ferry, after a 30-minute sailing with the engine off.
This is usually the only time that I have noticed the hesitation. Although once, on a long journey, with the engine behaving flawlessly, I stopped in a rest area for about 3 minutes and then immediately resumed my journey. The hesitation was there at high speeds, when I eased off the throttle; it felt like a loose CV-joint! After I stopped for gas many miles later, the hesitation disappeared.
After reading previous posts, I wonder if I need to reset the ECU?