So I just traded my 240sx for another 350z. Now i own 2. The story behind the 350z: The kid isnt very mechanically inclined but thought he could change the valve stems out with the heads still on with out any special tools. Then he realized after he took 3 of the cam caps off that he couldnt do the job. Well after he put the caps back on he was torqueing the bolts down with a BIG torque wrench. So he broke one. And thought the motor was done. So i traded the kid. I got the bolt out in maybe 30seconds and tightened all back down, put everything back on, made sure everything was hooked up and tight. When i started the car it puffed a small amount of smoke out the intake ONCE, and would idle at all, you had to give it gas to keep it running but it was still really rough! then it shut off and wouldnt start back up. Do you think it could be the cam and crank sensors? I just wanted someone elses input because i dont wanna spend that money and it not work. Im trying to get it running so i can sell it. The car ran fine untill it was taken apart.

 

Double and triple check all your connectors and make sure 1) they are tight and secure and 2) you didn't plug anything in wrong or backwards.

Sounds like you got did something simple wrong honestly. like the ignition coils out of order.

 

Just a suggestion. Put a subject in the subject line like

Squeaking brakes

instead of

Help

Need help immediately

or

If you don't help right away I will die!

 

Fixed the thread title…

Good luck with the issue OP, sorry that I can't offer any advice.

 

So i changed the plugs and put everything back together. It idles but really rough. Pulled the codes and p0300 comes up. Missfire somehwhere?

 

bump

 

Do a cylinder leakdown test. If the valves were damaged in any way while the kid was trying to replace them, then you may have a valve leak. That may be why the kid was trying to replace them in the first place. Also if the buckets were placed in a different location other than where they were inittilaly it may affect valve clearance resulting in a valve leak. Hope this helps...