Vauxhall Meriva throttle body sensor help please.

A quick run down of my problem is as follows:
Symptoms: Slow acceleration from a stationary position.
EML not on and no fault codes.

I replaced the throttle potentiometer. I also cleaned the ERG valve, MAF sensor and the throttle body. Neither was caked in carbon deposits.
With the ignition on (engine not running) and the accelerator pedal pushed to the floor, the throttle body “butterfly” is only open fractionally. Not sure if that is correct.
So, using an OBD 2 compliant a scan tool, and with the ignition on (engine not running), I pressed the accelerator pedal to the floor, and got a PID maximum reading of 32.55. My question is this: Can any one confirm if that figure is correct? Or indeed if the throttle body “butterfly” opening as described seems correct.
Sorry for being so long winded, but I thought the more info I can give, the more chance (hopefully) of a solution to my problem. Thank you in advance.