Hello, I currently own a 2000 Eclipse GT and have been having some issues with the car and possibly mechanics.. not entirely sure on the mechanics end of things but I specifically made a list of things that I have heard or felt the car doing which is..

1. Emissions code comes up on computer scan
2. 1 or several cylinder misfires according to scanner, not sure the specifics because multipule scanners said different cylinders.
3. Sometimes when I let off the gas and go to steer around a corner I hear a single knock like sound coming from possibly the steering column, I am not sure what it is but it is bothersome. I also have trouble replicating the issue, it does not always do this but sometimes it occurs.
4. Car may vary in RPMs in different ways. If I have the car in park it seems normal enough. If I come up to a red light and try to apply preasure to the breaks when the car finally stops the RPMs go way down from idle, sometimes as low as 200-300. I am not sure why it does this.
5. Could you also check the engine mounts to see if there are any issues.

The bill I recieved is as follows..

Spark Plugs + wire + cap and rotor $559, Computer test and Diag 89.95(DONE), R&R tie rods $114.90 (DONE), Fuel Service $99, front motor mount $279, Transmission mount $299, Lower transmission mount $106, Valve cover gasket $ 328 or its $199 w an included tune up, and to clean the headlights which at this point i dont care about at the moment is $39.

And btw I just got back from that shop, and I still hear the knocking noise that i mentioned earlier.

Any input would be appriciated, weather it be based on the price or what you would think may be the cause of this mess... (sorry I am not a mechanic I just love the Eclipse..)