Game/Car/Money glitch

I have been playing nfs heat for the last few months and I've noticed that at times when I turn off then turn back on the game I will sometimes have more money than what i had before i turned it off like i could have 12,000 and then I'll turn the game off and on again and I'll have over 100,000 dollars just given randomly and that turns into my cars glitching out with the tires being bigger and rims smaller and then i cant fix it or sometimes the tires dissappear and then that made my game start giving me game errors and kicking me out of the game entirely so ive had this happen once and now it seems to be happening again and i just dont want to restart the whole game and lose everything so just wanted to know if this will mess up my game and if there is a solution for it