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No I get it down to 1 or 2 left then it will get a check eng light for random misfire, I'm also getting a code for Misfire rate catalyst damage fault - Bank 1, also same for bank 2
Fuel trim or mixture out of adjustment can be caused by lack of fuel pressure , this could also account for the both banks catalyst faults as a pair being engine regulation then both catalatic part paths doing the same thing
The short term fuel trim target is 0.0 % in all engine ranges with + or - 3.0 % best expected from reading others
The fuel pressure is 43 PSI at idle and goes up tp 47 with throttle up
The vacuum line attached at the top of the fuel pressure regulator ?
Swapped the fuel pump relay ? the power contacts inside can be burnt limiting the current to properly run the pump , the pump motor connector can also have the sockets burnt , these are signs the fuel pump is giving out without plumbing in a pressure test
Might consider changing the fuel pressure regulator as they don't last forever , rubber diaphragm leaks into the vacuum line and into the intake effecting fuel trim rich
Main fuel filter chang ?
Injector cleaner ?
There are basket filters in each of the injectors and I have seen from reading if the car sits in storage for awhile rust ( poor metal of fuel rail and water in fuel ) will develop in the fuel rail migrating down to the injector basket filters
The basket filters with the fuel proof Viton green O - rings can be obtained on E - bay or sonic cleaning machine and can be removed by a ground down wood screw threads
Editing
There are a couple of things you can do easily with the O2 sensor wiring to improve their accuracy to hone in your regulation
There is 1 fuse # 14 / 10 amp right engine bay fuse box for all 4 O2 sensor electric heaters on engine start up before coolant temp sensor sees 88 degree C to go into close loop mode and only then using the O2 sensors
These heaters are needed for accurate O2 sensors reading and can be easily checked that they are not burnt out and intact
Inspect the Papa Indy 61 connector that has some engine regulation wires in it and the 1 power wire for the heaters , No O2 sensor returns come through this
The 2 Papa Indy 1 and Papa Indy 61 connectors are subjuct of a TSB on corrosion
Heater wire color is White / Green in postion 12
To know you are in close loop mode coolant temp wise the coolant sensor will read against a graph on page 78 , this sensor is common to go out from reading
The rear O2 connectors can get corrosion and get mixed in reconnecting.
The O2 return signal wire has a coax shield ground point on the rear firewall to protect the sensitive return signal . Best to clean both left and right small firewall terminal studs
The rear sensors are used for engine regulation and the fwd ones are for exhaust gas comparison for the catalyst efficiency CEL code 420 and 430
Exhaust manifolds not cracked ?
Cracked and leaking exhaust before the O2 sensors will bias the sensors to command fuel trim rich
Vacuum leaks and all hoses intact , map page 60 in the beginning of AJ16 section of 801S doc , I had a missing hose under the intake to the EVAP valve
downpipes gaskets not leaking and the 4 downpipe stud nuts tight as they come loose ( best gotten from bottom under car with 15 mm on ratchet extensions , ondon't use a universal but just place the socket squre in just sitting in the end to get about 15 degress e of the nuts has very little side clearance so I
Editing but on a roll
There is a name for the special end of the extensions that snap - on offers like maybe bevel ?
