I bought a 2008 Impala LS this summer without researching the car. I went down to buy a truck because ...

well for the tires on gm's very time there rotated they need to be traind so the sensor will then tell the computer where there at on the car and pressure (has to be done at gm dealer) as for the light its porbaly just the gas cap

check tire pressure when tire is cold,like in the morning,driveing it gets tires hot and build up pressure so if you gaudge a tire that has been driven on for several miles,it wont be right psi,for gas cap when it is removed and put back on turn it until you here it click at least 5 clicks,they say 3 clicks,5 or more is better.

your tire moniter has to be relearned at your gm dealer

okay just because the info center says check gas cap doesnt mean it he gas cap it could be the vent valve or purge valve take it to a shop to get tested and the tires senors can be set without dealer press info button till tire learn shows on dash with key on engine off and hold set reset button for about ten seconds the horn will sound twice and start at front left tire and increase and decrease tire pressure for ten seconds the horn will beep once go to front right and do same thing horn will beep once the back left and back right and upon completion the horn will beep twice shut off car and top off tires at 32 psi start car and scroll through info to get to tire pressures make sure all r read pressure check tires for pucture holes or rim leaks with soapy water solution