When I Play..Framerate is 1.5!!!

I’m trying to make a simple driving game, I wrote this code in the update function of the car “gameObject” function Update () { if(Input.GetKey(KeyCode.UpArrow)){ gameObject.transform.Translate(0,0,2); } }

Then I start playing… I Press to Up Arrow key, and the game is down from more than 60fps to 1.5fps! why ?!

UPDATE!!!
This error is caused if I add a Rigidbody Component to my car!.. I Don’t want to remove the rigidbody component, so what should I do?!

ANOTHER UPDATE!!!

I Fixed that error, it have nothing to do with my problem!

I Noticed that my Car is having sooo many meshes, I think that’s why it lags, so the question now is, how to export this car as a whole From google Sketchup! I mean to make it only one mesh… not multiples meshes

And this is a screenshot.[32895-screenshot+(7).jpg|32895]

Export your Sketchup to 3ds or obj.
Import it to Unwrap3d, and export to fbx, by default it’s only 1 mesh.
You can also reduce polygon count with unwrap3d.

Regardless of the amount of draw calls your car is, the amount of polygons being rendered will still evoke graphical lag. I suggest you use a less high-poly model; any video game 3D artist knows that being conservative is import (So don’t just download models from the Sketchup Warehouse).

That error seems to appear most often when you have a 2d plane attached to moving rigidBody.

Are you using a plan instead of a cube for the road by any chance?