420,430 are bad cat converter from engine miss of number 5 cylinder or code 305.
IGNITION COIL & POWER TRANSISTOR
The ignition signal from the ECM is sent to and amplified by the power transistor. The power transistor turns on and off the ignition coil primary circuit. This on-off operation induces the proper high voltage in the coil secondary circuit.
ECM Terminals And Reference Value
On Board Diagnosis Logic
Malfunction is detected when the ignition signal in the primary circuit is not sent to ECM during engine cranking or running.
Harness or connectors (The ignition primary circuit is open or shorted.)
Power transistor unit built into ignition coil
Crankshaft position sensor (REF)
Crankshaft position sensor (REF) circuit
DTC Confirmation Procedure
NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.
If DTC P1320 is displayed with DTC P0335, P0340, P1335 or P1336, perform trouble diagnosis for DTC P0335, P0340, P1335 or P1336 first.
Turn ignition switch "ON".
Select "DATA MONITOR" mode with CONSULT-II.
Start engine. (If engine does not run, turn ignition switch to "START" for at least 5 seconds.)
If 1st trip DTC is detected, go to "Diagnostic Procedure" below.