hi, i have a 86 accord lx-i fuel injected... i recently had a vaccume leak repaired due to smoke

okay, my friend asked me to teach him how to drive stick, so i decided to with this car, when he started it up he had the feet on the gas as he turned the key and the car was rumbling (he usually does this to his auto to warm up his car) then he released the gas... and the car started running.... but the bad thing smoke starts to come out of the exhaust pipe now.. WTF DID HE DO?!