Mechanic Job in Saint Louis, Missouri

HI,I NEED SOMEONE TO DIAGNOSE THE PROBLEM WITH MY VAN.I HAVE A 1995 GMC G2500 VAN 5.7 WITH ONLY 75,000 ORG. MILES,BUT I HAVE A CHECK ENGINE LIGHT THAT COMES AND GOES.I HAVE ONLY HAD THIS VEHICLE FOR ABOUT A MONTH,IM A DIY KINDA GUY, SO I WHEN I GOT IT,I CHANGED THE OIL,SPARK PLUGS,CLEANED THROTTLE BODY,REPLACED FUEL FILTER,BOUGHT AN O2 SENSOR BUT RETURNED IT,BECAUSE I WAS RECIEVING THE SAME CODE,I ALSO TRIED A DIFFERENT MAP SENSOR,BUT STILL GOT THE SAME CODE..... I NEED SOMEONE TO CHECK FOR VACUUM LEAKS,FUEL PRESSURE, AND MY IGITION SYSTEM AT A RESONABLE RATE AND TELL ME WHATS WRONG WITH MY VAN..... THE WAY,MY GAS SEEMS A LITTLE FUMEY,IT SUTTERS SOMETIMES WHEN I STEP ON THE GAS AND DOESNT WANT TO SHIFT SMOOTHLY AND THEN THE CHECK ENGINE LIGHT COMES ON,BUT ITS NOT THE TRANNY..... INTERESTED GIVE MY CALL OR TEXT WITH A PRICE,BLAKE