Car won't go pass 2500rpm, pls help, wants to stall with rev and engine light flickering Options

[malecrod]

Hey Guys, basically I just had my clutch replaced yesterday and the car drove fine. But this afternoon after driving like 3miles the car started hesitating like it wants to stall with some backfires and engine light coming on and off whenever I try accelerating pass 2500rpm. I also noticed engine light comes on for a second whenever I rev the engine pass 5000rpm and let off the gas. Car idle fine with but problem starts when you start to drive. Also I notice tempt shoots up during the hesitations and backfires.
what sucks is I took the car back to the shop that replace the clutch, he tells me the car was doing that before I brought it in, But I know for a fact it was not. Any ideas what the cause might be? Any help would be appreciated.
Thanks
Eli

[lagos]

take of your intake piping and check for any cracks or leaks that may have happened from them taking it off. then check your IC piping to make sure it didnt come undone when they had to tilt the motor to get the tranny off.

[malecrod]

take of your intake piping and check for any cracks or leaks that may have happened from them taking it off. then check your IC piping to make sure it didnt come undone when they had to tilt the motor to get the tranny off.

Yes the intake piping was the first thing I checked and tightened up. I went back and tightened all the others, no cracks that I can see. I replaced hoses that felt a bit loose. Replaced radiator cap and added injector cleaner plus an octane booster yesterday(bad gas? ). As of last evening, I haven't had any problems. Will check the plugs tomorrow.
Thanks