p0102 and p0307

[04 silerado dave]

I recently purchased a 2004 Chevy Silverado 1500 with a 5.3. Get a blinking CEL on acceleration. code reads p0102 and p0307. I already did a tune up on the truck, new plugs and wires oil change. truck has 189,000 miles. the kid I bought it off did god only knows what in repairs. the evap purge hose on the top of the engine was replaced with heater/fuel hose goes back behind the engine to a hard pipe. the evap canister underneath the middle port has a random hose going to what looks like a 3 port filter connected (I'll see if I could post a pic). it definitely has a rough idle. also not sure if I here a hissing noise around the manifold. does anyone have a vacuum diagram of the evap system the hard pipe the purge valve goes to seems to go direct to the tank.

[Brian715]

Your p0102 is a MAF code. Doesn't have anything to do with the EVAP system. The p0307 is a cylinder 7 misfire so if it's blinking on acceleration it means #7 is misfiring badly. Check the coil with a spark tester, I would probably check compression on #7 of spark checks out. 

[04 silerado dave]

Checked compression when did the plugs. Wouldn't EVAP cause vacuum leak after maf.