Sentra will occasionally not start. (plugs, fuel, engine, replacement)

[jtur88]

'01 Nissan Sentra. After shutting off engine, it will not restart. This occurs maybe 10% of the time. Solution: Hold down gas pedal while cranking (still won't fire), then wait a moment and crank with foot off gas, and it starts. Electronic diagnosis reveals no codes.

Question: Is this normal? It occurs even on cool days (6o degrees). Running temp is normal. I know that this happens sometimes on very hot days, when any car can be hard to restart, but in this case, there is no firing at all. It's like cranking a dead engine. But the above solution works every time (so far) and the owner's manual addresses the situation and suggests the pedal-down remedy, but does not say that it is necessary to try again without pedal after that.

My guess was that each car is different, and this car, by the laws of chance, happens to run at a temperature that is critical to the computer. But this occurred both before and after replacement of the thermostat. This is a newly acquired car, so I know nothing of its history. Otherwise it runs perfectly and efficiently (35 mpg). I checked plugs, and gaps are right on.

[Narfcake]

I'm not familiar with the more recent Nissans, but a failing crank position sensor can wreak a lot of havoc; the computer relies on it to determine when to inject fuel and fire the plugs ... without the information, it won't do anything.

[jtur88]

Originally Posted by Narfcake

I'm not familiar with the more recent Nissans, but a failing crank position sensor can wreak a lot of havoc; the computer relies on it to determine when to inject fuel and fire the plugs ... without the information, it won't do anything.

Wouldn't a failing sensor show a code on the diagnostic? It should hold the code from any prior malfunction, unless cleared. It did still show a code for the failed thermostat, even though that had been replaced.

[jtur88]

Originally Posted by Narfcake

I'm not familiar with the more recent Nissans, but a failing crank position sensor can wreak a lot of havoc; the computer relies on it to determine when to inject fuel and fire the plugs ... without the information, it won't do anything.

Thanks to your tip, I checked recall notices on the car, and there were two separate recalls issued for exactly the function you described---the crank position sensor. So Nissan ought to repair it for free.