the guy i bought my 2000 chevy blazer from, said that there is a bit of hesitation taking because he didnt conect one of the wires when he changed the fuel pump.(something about the gas return line or wire)...there is a brief suction whistle like sound at the beggining of acceleration. why would he leave something unpluged to begin with im not sure, but anyways my question is does this sound right, will it be waste of time pulling the gas tank. please help also the codes are:
* exhaust gas recirculation closed position performance ?
* evaporative emissions system vent control circuit ?

 

Anything evap related will usually have to do with the fuel system. If the guy didnt plug in all the wires where they need to go, I would certainly make sure I did just so that I wouldnt have to replace a fuel pump anytime soon. The manufacturers put those wires there for a reason, I would listen.

 

cruizing at low speed then slightly accelerating, (like easy trail riding) makes the blazer bog down just for a split sec, meanwhile making a brief whistling/air sucking like noice from under the hood. it will only do this while slowly cruizing, as on a gravel road. now, if i accelerate quickly, it doesnt do it