2000Nissan Frontier, 4 cyl, 2 whl drive, auto, about 72,000 miles. Started up, drove 1/8 mile( ran smooth) then engine sputtered a few times, then conked out while driving. Engine cranks but will not restart. 1st time this happened.

Disconnecting the battery could reset codes and/or sensor readings in the engine computer.
Is the check engine light on, and have you checked the computer for trouble codes ? Is fuel pressure normal ?

You need to find out what is missing when it won't start , spark - ignition system or fuel pressure . No Start Diagnostic Basics EricTheCarGuy

1251 Air Temperature Internal Sensor Circuit Open



1260 Solar Radiation Sensor Circuit Short To Battery





HOPE THIS HELPS

The car wash pressure may have disconnected an electrical connector part way or completely. Check for this all around the engine and transmission. Touch and wiggle all of them! Dont forget to check under the car all the back to and around the gas tank. Also check for a vacuum line that is popped off or even broken.
Aside from that, water has got into something. Check all power distribution boxes for moisture.
If you dont know how old the plug wires are, or they are the originals, you should replace them.
With plug wires, its the age, not the miles.

The 2 components that I would suspect would be the Coil pack and the Cam sensor.
I had a similar issue on a Sorento. Intermittent miss on one of the cylinders. The Coil pack was bad. When I replaced it, there was a burnt smell to the bad one. It sounds like things were a bit bumped around with this engine as the O2 sensor was bent. The Coil packs are very fragile.
Hope this helps. God Bless

First check all wires for any thing loose.
The muffler blowing up leads me to think the engine is so far out of time the PCM cant correct it.

REally you need to get it to a good mechanic.

It sounds like an ignition problem. Make sure your battery is good and connections are clean. I would start by replacing the plug wires and spark plugs. This is a good tune up procedure anyway and will increase your mileage some. Clean or change the air filter. The obvious thing is to make sure the oil is new and filled to the correct level, not overfilled. Your engine will love you. I hope this helps.

THE STARTER IS GOING BAD

There is a little tester calles a NOID, it plugs into the harness connector to the fuel injector and flashes if there is a signal, they only cost a few dollars.

bad. compression in the engine.