Yep, confirming this problem at my PS3 too! And low frame rate too, cars are overreacted with control.

Have you also noticed that after crashing you they either drive right through you, or drive off at a crazy speed? My McLarin P1 got "stuck" to one of the invisible cars (as I call them) and drug down the interstate backwards until I had to reset my game.

 Ensure your router or modem's firmware is up to date.

 To do so, you'll likely be able to find help from your router manufacturer's website.

There are several solutions you can try in order to improve the connection on PS3.

• Connection / Network Issues with PS3

• PlayStation players can find both Wired- and Wireless-specific support from Sony.

Yea, I went through it again about a week ago. Tech support walked me through it when I first got the game. There are just invisible cars on the game. Cop and civillian. Just another glitch to deal with. Yes it can be frusterating, but honestly it has led me to witness some of the most incredible and funny crashes.

there is one more issue with nfs rivals which was very well sorted out in nfs hp-

i)whenever the car gets crashed it does not get relocated in the correct direction and due to this many times i startmoving in the wrong direction. this results into the easy escape of racer when i play the cop.

ii) the mini map on the bottom left of the ps3 tv screen is so small that as the car crashes the racer vanishes which is obvious but he is unseen in the mini map also. the "range"  of the radar of the car should be increased in the future upgrades

or an auto tag or routing to get back to them! I usualy stop, switch to my map, find them, click on them and rout back to them!