Hello all! I am new to the board, thanks for the add.
I just picked up a 2003 305Z. I knew going in that there would be a few issues to work through but I am now stumped.
Here's the problem:
Car runs perfect from start up to stop. After it is turned off (after running her for while) and then restarted, then it misses like crazy. It will miss, it smells very rich, it will also back fire.
So far I have killed the cats. I am now running straight pipe to the muffler. I have changed the plugs. I have cleaned the throttle body and the MAF.
Again, the car runs absolutely flawlessly until it is restarted. Is this a coincidence or does it have something to do with the restart? I bought this car as a repossession. It has an aftermarket key. Could this be causing the problem? If it was, shouldn't it not start all together or never run right at all?
I am at my wits end and do not know where to go from here! HELP!! Thanks in advance!

 

These guys should be able to help you out:
http://www.harrisonburgnissan.com/index.htm

 

I was trying to avoid the dealer if possible. Was hoping someone on the forum could help.

 

You need to get the codes. That will provide the solution.