my engine bogs sometimes from as soon as i start it all the way through accelerating, the check engine light reads cylinder 1 misfire, cylinder2 misfire, cylinder 4 misfire, and multiple cylinder misfire. I have changed rotor, wires, cap, coil pack, fuel filter, and the injectors about a year ago..It was doing this the last time i changed my injectors and it fixed it for about 6 months with no problems. I did drop my gas tank and clean it out, and it had sometime of sand in it. So im thinking the injectors may be messed up again. Ive removed them and tried cleaning them out. ive changed the filter several times. Engine i believe has good compression 180-190. Are there any sensors that could be making my engine misfire? sometimes the car smells like its running rich too.

 

Pull out all plugs and see how they are burning.

In any case, any mechanical parts are either work or not work. They don't care how new /old they are.

Start changing less expensive parts first, one by one.