I recently bought a 93 blazer and it ran when i first bought it but not very well...a short time later the battery and the spark plugs were shot so i replaced that and right after i replaced the spark plugs it ran like brand new but the next day it was running like crap again...what could be the problem?

Also, when i first bought it the fuse for the interior lights was bad and my right turn signal didnt flash but it lit up so i replaced the fuse and i found that one of the bulb in the front wasnt working so i replaced that bulb too and all the interior lights and my turn signal was working but after i changed my spark plugs and drove it a little while the fuse burnt out and my right turn signal isnt working again...idk what it could be?

 

do you live somewhere or did the care come from somewhere it snows and rock salt is used to melt it? stupid question i know but i live in vegas and don't have corrosion issues. the lights sound like a short in the wiring. also does your truck have a tow package i have seen many times were people have a tow package with no seal on the connection cover and once water dirt etc shorts out and causes the fuse to blow. on my 93 i bought was a power line maintainer so it spent most of its time in 4x4 but also at almost idle the whole time. the first time took it on the freeway it ran fine but when i got off the freeway it stalled out and died giving me no power brakes or steering, let me tell you it is not fun trying to get a car to stop at a light from 65mph with no brakes. Took it to a shop and they said there was massive carbon build up on the ______ i don't remember what it was called but he cleaned it out and it ran great and started again so i took it back and he did it again that fixed it for good.

 

yeah i bought it from a friend of mine and my friend got it from a guy who lived in colorado so it could of been around a lot of snow

 

Like posted, could be simple water in the bulb sockets. Pull the bulbs and spread electrical grease on the sockets connections.

As for the running like crap, can you be a little more specific?
Have you truied Seafoam through the gas tank yet? Again, it could be water, this time in the gas.

 

I agree with Hanr3 check your bulb sockets to see if condensation is a problem!! The other issue try a fuel system cleaner or the seafoam treatment to the gas tank!!