2001 D-Max. I am experiencing PO234 when towing my RV (10K lbs) uphill. I have had the boost monitor replaced. The truck does fine until I near the shift point for 5th gear. My boost gauge reads 15 - 17 lbs. The throttle is removed until the truck slows to around 40 mph.

I have had the Code PO234 several times and it is the only Code I get. I had a PCM reflash in 2004, which solved this problem or one very much like it. All intake connections have been verified as good.

Would another reflash of the PCM be helpful? Is there a newer version of software for the PCM or can it revert somehow, back to a prior level (Glitch)? What else should I look for or do to solve this pesky event?