02 tacoma

I need help! I just bought an 02 tacoma. It was driving fine but now its sputtering and check engine light is on. these are the error codes that auto zone gave me. p0300 random/multiple cylinder misfires detected. p0302 cylinder 2 misfire detected p0115 engine coolant temp circuit malfunction. p0770 shift selenoid E malfunction. and then under DTC pending there is another p0302 cylinder 2 misfire detected. Now to admit that i'm stupid....the engine compartment was really dirty so i sprayed it with cleaner then hosed it out. do i need to take this to a dealer? Please help and remember i already called myself an idiot. thanks grant