We own a 2004 Nissan Sentra with 100,000 miles on it. It runs fine and is in good shape. The one problem we do have is that after it sits a couple of days in the garage it does not start. We have replaced the battery and the spark plugs to no avail. Our mechanic reports that the engine sensors and computer diagnostics do not report a problem. It turns over fine and sounds like it is about to start, but it usually does not. After swearing at it a few times, and trying to pump the gas pedal, (a no no for fuel injection cars), or holding the gas peddle all the way down it might start. Should we replace the fuel injection system?
I suggest you check to see if the injector is leaking and flooding the engine with fuel while the car sits. If that is the trouble you just need to replace the injector. In no case should you have to replace the whole injector system.
A couple of weeks ago Tom and Ray were talking about a similar situation on a Honda that wouldn’t start, similar to yours. But it was hot temps in the car’s cabin after the driver went to the store that was causing some sort of sensor under the dash to go bad, then return to normal when it cooled down after the owner returned and rolled down the windows.
If it will do the same thing at the repair shop, I’d suggest the mechanic check on fuel flow to the injectors. The Honda’s sensor was preventing the fuel pump from working. Maybe you have a similar situation.
Getting a qualified diagnosis usually beats thrown parts at a car.
Try leaving your key in the on position for a few seconds before you try to start it. This will allow the electric fuel pump build fuel pressure that that may have leaked off through an injector.
I don’t see where anyone has checked the charging system. Many auto part stores will check it for free. At the very least check the battery voltage running and with the engine not running. Should be about 12V not running and something about 13.5V running.