-- tightening belt too tight causes bearing failure .. there is an oem recommended play for the belt for every vehicle (check manual must be around 0.5") .. with optimum belt tension; if ur belt still squeaks that means a sub-standard quality though some better quality belts also squeak for a couple of days after service or rain
https://www.pakwheels.com/forums/belts-pipes-hoses/237916-drive-belt-noise-after-rain#post4539911
-- a vibration on flooring the paddle mostly means that ur not getting suffient fuel or burning .. these could be the probable reasons :
--- fuel is available but air is chocked
--- one of the coils or plugs is weak
--- one of the injectors is not giving right amount of fuel
--- clutch or pressur plate worn
do a standard process .. get it tuned .. check gear sys, plugs and coils .. leave injectors for now, since injector failure on high rpm could be a current issue not necessarily a chocked injector