P38 tuning box disconnecting ???

Hi all been looking at this site for the last 3 months and now proud owner of a 2.5 P38 , Read all the posts regarding remap and tuning boxes and was loooking forward to unleashing those extra horses!!!

However after a bit more time looking round the engine bay relised it'd already been fitted with a ( CLM4 PBox motertuning ):doh:
Now dont know if its just me expecting more but the car doesnt feel that quick , The box seems have a plug and lead thats spliced into a small loom on the side of the engine and also a single black wire connected to a plug on the top of the fuel filter ,

Soooo the question is can i just unplug this lead and will this then make the car run as standard or is it a little more complicated????

If it's cut into the cable then it's not going to be easy to remove. In the case of mine the cable is unpluged from the engine, plugged into the box and the new cable from the box is plugged into the engine.

Why would you want to unplug it and get the performance of a slug?

2.4 tonnes of 4 X 4 is never going to feel very quick even if the box has pushed it up to 160bhp from the standard 136.

know what you mean with the boxes with 2 plugs , thought they were all like it.

Just want to unplug it to see if its actually doing anything??