So my gremlin still exist.

I keep getting code P06D3 Sensor reference voltage 5 circuit low.

What I have discovered is when pulling a load mainly up hill the truck will sputter and loose power and throw the code and check engine light comes on.

What I have noticed is that the rpm's are getting down to about 1500 rpm and the truck should be automatically down shifting.

If I manually shift gears and keep the rpm's up 1800 plus the truck works great. Also, I feel my fuel mileage is suffering.

So here is my thoughts on this. I have already changed the crank and cam sensor's, and am wondering if the MAP and Mass Air Flow sensor's are bad.

The truck starts easy and runs fine, I just feel I should be getting better fuel mileage (about 16 mpg actual).

Another thought is that a solenoid in the tranny (Asisn) is bad.

Any input would be appreciated.