Whenever i let rpms drop or hit brakes my car engine lights come on like its dead and a buzzing sound comes from under steering wheel it sounds like... and my lights r alot dimmer then before...some people have tol dme maybe its alternator(not rx7 people) so though id post up on here and see wut u all say and also when i rev it sounds like my belts squeaking after i took off smog pump and smog pump belt :S
any help is greatly appreciated thx!!
Tony

 

Check your alternator and make sure you have a good battery. Mine did this when my neg. battery terminal came off while driving. (minus the check-engine light. S4's dont have one)