I have a '91 305 tbi 5 spd. when I take off I hear a gurgling or knocking sound when ever I am accelerating. I can put the car in neutran and rev it and no noise but whenever I'm in gear and accelerating it makes this sound and its getting worse. It sounds like its coming from the engine bay. Anyone have any idea what it could be? I have a fear that this is going to cause some serious trouble if I dont get it fixed soon.

 

Does the pitch of the sound vary with engine RPM or road speed? One would indicate an engine/clutch/input shaft problem, while the other would indicate a transmission or driveline problem.

 

Exhaust leak?

 

sounds like pinging to me. check your ignition timing first. then check/replace knock sensor. try checking the timing first and report back with results.

 

Ill go with the ignition check. just replaced clutch pilot and throwout bearing. the noize was there before i did that. I thought my cat was going out but the noise seems to come from the engine area. same sound at all speeds just a little louder with more pedal.

 

I just has something similar and it turned out that my Cat bolts were working loose.