hi,1991 crx dx surges at any speed hot or cold.tack goes up and down and sometimes dies. sometimes it runs fine. what has been done to fix the problem with no luck by a certified honda mechinac.checked timeing,replaced disturbuter,rotor cap,plugs and wires,idial control valve,fuel filter,fuel pump,gas canister,water remover,altnater,battery.he gave up after lots of money spent. thanks