[triggerhappy101]

i have a bit of problem with my mustang, i have a 94 mustang GT V8 5.0 302 engine, its only got 66,000 miles, the body and interior r like new. my main problem with it is when accelerating at times ill hear a rattling sound. mainly when going from second to third and third to fourth gear. if i accelerate slowly it doesnt do it but if i push the gas petal down to far ill hear it. ive been told its my EGR valves n they need to be worked on or just taken out, any thoughts?

[beheivjer]

never heard of egr doing that but i guess anything is possible

[RockerShocker]

sounds like detonation. My 95 has been doing it, and i think i got it stoped. ANd it was the EGR. SO, you can either unhook the EGR vacuum line, and plug both sides, or buy a new one and swap it out.

[Bullitt95]

Yes, it does sound like detonation and one common cause is the EGR valve getting stuck open causing the engine to run too lean. You can either take it out, clean it, and reinstall it, or just delete it altogether and plug an EGR eliminator simulator into the wiring harness to prevent the "check engine" light from coming on.
Another possibility is clogged injectors causing a lean condition though with just 66k miles, this seems pretty unlikely. You can try a fuel system treatment with a bottle of injector cleaner and see if that helps.