I have a 2006 tl and was wondering about the tpms reading. How accurate is it really? I kinda think its not all that accurate.

 

its accuracy is + or - 1 PSI. Its pretty accurate, but the point of the TPMS is not to give you exact info to see if your tires need air, its to tell you:
A. you are loosing air due to a nail in the tire
B. You have a blowout due to tire failure
C. Air pressure is below 29 PSI