Car will run fine but when you turn it off it won't restart.
 

I've been away at college and my poor 240 has been sitting neglected. I finally got a chance to put it back together and now I'm having a weird issue.

The car starts and idles just fine. When you rev it, it doesn't bog or anything.

It will idle just fine and be perfectly normal. When you turn it off though it won't restart. You can crank and crank the motor and all you end up doing is flooding it out. It won't start again untill you leave it for a while and come back to it.

I checked the check engine lights today and I'm throwing a code 21. No ignition reference.

This sounds important and that it could be my problem but i have no idea what it means!

Help!

Re: Car will run fine but when you turn it off it won't restart.
 

Check your fuel relay. It happen to my brothers civic couple weeks ago. It wouldn't crank over for nothing. He ended up like you flooding it and when he leaves it alone and comes back it starts. but i don't know how Nissan works. Haha.