Gameplay issues:
Too grindy.
The spongey suspension and incredible fuel consumption makes going up steep hills nearly impossible at the beginning, which makes getting money a slow and frustrating process, especially after getting several upgrades. Perhaps make the level generator gradually make the terrain get rougher the closer to the finish you get.
Rabbit shouldn't die at the first moment he flips over. I've been able to recover, but he ends up exploding anyway.
No info on what each stat you're upgrading does.
End money collection takes way too long to count up. A click should make it instant.
Needs sound and music mute options.
Bugs:
Carrot collection is spotty. Sometimes I'll collect them, sometimes I won't on very obvious mouth/head hits.
Reverse doesn't use fuel.
Engine sound goes away after running out of fuel and then collecting a carrot to continue.