Hmmm possibly but I doubt it would make a huge difference. What kind of intake is it? Is it a cone filter intake such as a K&N? You should definitely be running a heat shield if it is IMO. Otherwise your just hurting your performance even more than you already are.

 

Some color for you:

I have an 2009 IS350. Only mods is a K&N intake & 19" wheels. I mainly use it to drive 9 miles to work, with moderate traffic. The best I have gotten is about 18 mpg. The worst is about 14. I seem to average 16-17 mpg.

Full disclosure: I drive it like I stole it...Almost always in S mode, addicted to the sound of the intake in the at 6000 RPM...PWR Mode on...Snatching spots from slower cars...

My advice: Life's too short to drive slow...gas is cheap...drink it in.

 

I have a injen intake, the pipe gets at times. I'm getting a heat shield soon to see if helps the pipe from heating up