i bought this 1991 v6 bird a week ago. Since we bought it, it would normally take two tries to get the car started, and it'd be fine. Then it got progressively worse over the week, at one time taking 4 tries to get it to start. The other day my gf couldnt leave the house because it just wouldnt turn over. It would crank, but not turn over. she went back later on and it fired right up. My buddy n I did a tune up on it last night, and replaced the pcv valve, cap, rotor, and plugs. ( wires were fine). So we got it to fire up on the first try, but the car runs rough. It almost sounds like it's got a cam. When you put it in drive, and attempt to drive it down the street, the car has no power at all, and backfires. We made sure all the wires were routed correctly. The fuel pump is relatively new, and so is the cat. What could possibly be wrong?

 

the distributor may be turned out of time.