cold runs fine warms up it misses
 

My 1998 chevy blazer runs smooth as your wifes. well never mind u know. anyways When it is cold runs smooth. after warming up it runs a little rough. I installed a new fuel filter in it and it had water in the filter. I was told buy some shop guys not to worry about it. its just condasation in the tank just add heat and it will be fine. well it was running the same way before i changed the filter and added two cans of heat and after i did all thatshould i take filter off again and check it? or might be some thing else. new plugs,wires,cap. air filter is clean (see through it). any help or sugestions would be nice. (sorry for the spelling not my best thing)

Have you cleaned the EGR valve and MAF sensor?

maf sensor yes but EGR valve? I am not shure were that is i think it is right next to the thermastat houseing? no and should i? how would i clean that and with what?

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