I fixed my hard start problem, but now the car still wont start but I have a new issue that not sure how to figure out.

If I press the gas pedal down and attempt to start it I hear like a deep thunderish roar coming from the engine, and after a few attempts it backfires out of the intake. The tube coming from the throttle body/airfilter housing that leads to the front of the engine beside the battery puts out a big thump of air.

I have never known nor seen this car backfire before, and the fact that it if backfiring in the intake (still stock) has me totally confused. Any ideas?

BTW - the plugs are black (too rich) and I smell alot of fuel.

I have checked many things which finally got it to crank over. (Different post Maxima in Trouble)

 

If u kept cracking for a while maybe u could've flooded it? The roar is because youre cranking with the tb open... that's normal. Dunno about the backfire :S

 

Maybe you need to check the Engine Coolant Temperature sensor (ECTS). If all the plugs are black & wet, this is a possibility.

 

any other thoughts on how to resolve or what to troubleshoot?

 

Valve timing may have jumped. Injected cars dont generally have enough fuel in the intake to backfire, could be a bad fuel pressure regulator leaking into the vacuum line.

 

Any codes?

 

Check codes if any

 

make sure all of your intake piping is tight

 

No codes and intake is tight.