i changed my oil and spark plugs last night. after i finished i started the seadoo. it ran fine tell i gave it a little throtle after that is started vibrating really bad. i put the old spark plugs back in one at a time and stated the seadoo after every one to find out if one of the new ones was bad but after putting all the old spark plugs back in it was still vibrating relly bad. i got mad so i put everything back together and left it for the night. i woke up this moring went out and started it and it ran fine. anything i need to worry about? or any tips that would save me from a trip to the dealer. its a 09 seadoo GTI se 130