Looking at other submissions here, response was POAC4 is a generic "IMA not working code". Dealer explained that code is "Hybrid Battery Pack Current Sensor Circuit High".

Can anyone else confirm this explanation and potential diagnosis?


This car ran perfectly until timing belt change at 105K. Current mileage 160K. Since then MFI periodically comes on. Code says fouled spark plug(s) Changing fouled plug(s) is only a temporary fix (5 K miles). Dealer has changed all spark plugs, adjusted valves. Compression testing shows near perfect in all cylinders. Occasionally indicator light for hybrid battery comes on but goes out. There has been a rumble for some time when the electric motor syncs to the gas motor shutting down some of the cylinders. the VCM system The dealer thinks the fix to all our problems including spark plug fouling is changing the torque converter. We're slowly being bled to death.$$$$. This motor is computer controlled. I'm suspicious of known issues like the already mentioned VCM system, the Powertrain Control Module (PCM) or other electronic issues like fuel pump relay. Perhaps the computer needs to be reloaded like PC's. I know there are others out there having the same problems. Let's get together.

The problem has started yesterday. What can I do to fix the problem? Is it fixable? It hasn't had a diagnostic performed.