2005 Hybrid with recurrent engine/IMA lights

This is driving me to the poorhouse!:shakehead

I have a 2005 Honda Civic Hybrid with about 120,000 on the clock. For the last several months, I've had a recurrent problem with the "Check Engine" and the "IMA" lights coming on, either together or one at a time.

So far, I've had the catalytic converter, the plugs, the air filters and the sensors replaced. It keeps happening anyway. The mileage drops off from the mid 40's to the mid-upper 30's when these lights go on. I must have dropped $1,500 in this car for this problem since it started. :eek7:

The trouble codes are the same as the last several times.
P1130
P0139
P1600
P1433

Anyone have any ideas on what is causing this? I'm tired of taking taking it back to Honda. :disappoin

Contacted a Honda mechanic offline who tells me that it's probably a secondary O2 sensor and the main battery pack. I am not amused. That's a $3K bill all by itself and I bought the car as a Honda Certified Used Car. I'm still paying for it.

If he's right and we can't work out something with the dealer, this will be the last Honda I buy.