Hello all. Here is my issue that I'm wondering what next step i should take. Have a 03 S-10 ZR-2 4x4 4.3 V6 ext. cab. Had a check engine light on with code p0300, multi cylinder misfire. Connected my Snap-on computer to it and found that cylinder 3 had multiple misfires. Performed a tune-up, cap, rotor, plugs and wires. Truck ran great. Code gone. Took it for a test drive and while getting of the highway, the check engine light began to flash repeatedly then turned off. No odd throttle response or shifting to note when the light was flashing. Happened twice while on the highway. Got off and got back on the highway and it did not happen again. No codes found in the history. Unable to get the light to flash again or and codes to come back. Then the next day when i started it up, have check engine light steady with codes now P0303(cylinder #3 Misfire) and P0101(MAF sensor circuit Range/performance problem). Don't wanna just throw more parts at it with a MAF sensor code. Also im leaning towards checking fuel injectors due to the tune up and again cylinder 3 misfire. Any help would be appreciated. Happy Thanksgiving to you all!!