i recently picked up a 1986 rx7 5speed non turbo from a neighbor. first thing i noticed was a swooshing noise from the trans area. this noise is present in neutral and all other gears except for when the clutch is disengaged. first thing came to mind was a worn pilot and release bearing so i changed both bearings and clutch components. this did not remedy the noise so is this swooshing normal? is this the sound of sloshing fluids or is my trans about to go out?

the second concern is of an intermittent rough 'low' idle. i believed that worn clutch bearings could be putting a load on the engine causing a low idle. that wasn't it. i changed the fuel filter but the rough idle continued. is there a common component or problem i should check out to fix this erratic idle. at sometimes the car even dies because the idle goes so low. because the condition is intermittent i am kicking my self trying to find out the problem any help comment is greatly appreciated.

mahalo,
ty