i have 19in rims on my TL and the tire size is 245/35/19

whats the right amount of PSI should i have in the tires?

 

Start with what it says on the door sticker?

 

The TL door stickers and manuals have pressures for the 17" and 18" wheel/tire combos, but not larger ones.
Start with whatever the rim manufacturer recommends. If the rim manufacturer paperwork is missing, I'd start with the A-Spec recommendation (39F/36R, IIRC) and contact the rim manufacturer by e-mail.
Maybe Tire Rack has recommendations that address this issue at "tirerack.com" as well.

 

I put 38 PSI in my 235/35/19

 

isnt 38 a bit too much?

 

No, it's fine for daily driving on certain wheel/tire combos.
Acura's recommendation is 39 Front and 36 Rear for the the 18" A-Spec wheels. I wouldn't go more than 40 psi (measured when the tires are COLD) on any tires for day-to-day driving.
I run 37F/34R or 36F/33R on the stock 17" wheels.
Check Tire Rack's site to see what psi ranges it recommends for your size wheels (19 X 8.5??) if your wheel paperwork doesn't address it.