Mazda 6 2006 manual transmission

Symptoms

Delayed Rough idle (rpms go up and down constantly after a few seconds), engine hesitation and hard buckling/jerking in second gear, burning rich. Most recently, the gas pump nozzle was shutting off during filling (have not been back to fill up)


CEL CODES

Originally had two computer faults: P0401 - EGR valve insufficient flow and P0138 - downstream oxygen sensor high voltage (possible linked to severe exhaust leak). Exaust leaked fixed and codes went away.

NO OTHER CHECK ENGINE LIGHTS.

The air fuel ratio fluctuates (reading from obd2: torque app) and i think the computer is erratically causing to much fuel to enter the engine.


Things that I've also changed based on forums research


The EGR valve
downstream oxygen sensor
spark plugs
ignition coils
map sensor
Air intake sensor
Fuel pump
Solenoid purge valve
Fuel injectors.
Checked the intake accordian tube for cracks

Issue still not fixed. Any ideas?

 

You wanna perform smoke test .