since ive owned the car its always had a rough idle. Thru the rpm range its fine and pulls hard.
when i first start it no matter cold or hot after the initial start and once the engine drops down to normal idle then it starts missing. Ive tried pulling each wire while running and all cyl's seem to be the same as far as rpm drop.
Its got new plugs, ( rn12yc gapped at .035 ) wires, cap, & rotor ( a-zone brand ). MP performance computer, MBC, new timing belt ( set correctly ) timing set at 12 deg. the motor has 128k on it. My boost gauge shows about 16in. vac at idle. fuel press. is 56psi with vac line disconnected.
I just cant pinpoint the problem and dont wanna start part swapping.. any ideas ??
** update ** its a TII motor, on the throttle body there is two metal nipples sticking upward, one is larger in diameter than the other. The larger one is where the hose that comes off my pcv goes and the smaller one was capped. I use it now for my boost gauge. Just screwing around i swapped the hoses around and the motor smoothed right out. Any ideas whats going on ???