i went have a car stereo installed and they messed up all kind of stuff,so i just got my car back from the dealer supposedly fixing everything and now it seems like my car doesn't turn over as quick as before.... any suggestions?

 

Id say needs a new battery...
Most batterys only last for 3 yrs... I'm guessing you haven't recently replaced the old battery with a new one purchased from a store/auto parts... That would be my best guess/estimate at what the problem is.... To be safe.... I would have the battery load tested...
as well as have the alternator tested as well to be sure .

I'm sure someone else will chime in with more ideas as well...

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