HLA (hydraulic lash adjuster) 1996 OB Wagon Auto-2.5L - (made 07-95) with Sq plug wires, kinda sure that’s what type I got. any other way to identify lash adj? other than valve cover R&R? Just bought the car last week and am getting ready to chase a PO304( cyl 4 misfire) with NGK plugs (going with Iridium) and still looking for wires- been reading the threads- either OEM or NGK, nobody stocks them

the only way to tell, short of looking inside, is to call the dealer with the vin.

 

mis-fires are usually wire or plug related. NGK plugs and subaru wires. you can try moving the #4 wire to another cylinder to see if the misfire moves with the wire.

 

if that does not do it check the compression on #4. burned exhaust vavles are not unheard of, but it is usually wires.

Square plug wires are the large combustion chamber heads/VC's and those have the hydro lifters. '96 is the first year of the EJ25D and they have hydro lifters so if the engine is original (sounds like it) then it does not require a valve adjustment. It does call for premium fuel though.

 

GD