Fuel problem

[Lee P]

Hi guys, i mapped my car with my RS tuner for the first time yesterday and ive just been in the car with the fuel needle 2 bars from the bottom and the low fuel light has come on on the dash. Also when i use the rs tuner i cancelled the toxic emissions light which is from me having a decat, when the fuel light came on the toxic emission light came back on too? Lastly i turned the engine on with the trip computer button in to look at any codes on the screen. There is a 't' in the first space and the rest are still dashes.
Btw, do i trust the fuel needle or the fuel light? Should i fill up?

Thank you in advance,
Lee.

 

[Lee P]

Just reset the 't' code on the dash and it is fine. I got scared and put £20 in the tank. Will wait to see if the light comes back on at the same level on the fuel gauge.