Engine problems Need Help Desperately

I bought a 92 3.1mfi Lumina sedan almost a month ago. I was told that the car had a timing issue so I had the Timing chain and both pullys changed. I just got done changing all plugs and wires and the 3 coils.

The problem is....It wont start and when I try to start it, the Air intake tube(the one that goes from the Airbox to the engine)fills with gasoline.
I am a novice mechanic and have NO IDEA what to look for as the problem next.

Thanks in advanced,

Zivon23

You've got the timing cogs clocked wrong. That's the only way I could see it pumping fuel BACK into the intake. If the cam timing is wrong, that can happen.

ok...How do I fix that?

The more detail the better.....Thanks in advanced

There's timing marks all over the place. The goal is to just get everything at TDC #1. The crank is easy, just line up the timing mark on the crank pully with the timing cover mark. Pop the timing chain cover off and line up the cam sprocket with the crank sprocket. When they are in perfect line with each other, the timing marks on the crank sprocket and cam sprocket should both be at 12 o'clock. Slap the chain on, bolt up the timing cover, pop the crank pully back on (line up the marks, ensure the keyway will let you), hook up everything, and give it a go. Mind you, this is just for the OHV 2.8/3.1 V6, not the 3.4 DOHC.