04 Accord Sedan - V6 VTech Engine - 155K miles.

My engine has now twice just shut itself off - gone to zero RPM. Both times where when I was stopped, one time the engine was cold the other time it was hot. Turned the ignition key and both times it fired right back up.

I'm thinking what could this possibly be? I did notice that once when I turned my key to the accessory position to just roll down my windows, the check engine figure flashed for a bit (but then disappeared). Should I go to a mechanic and have him look at the diagnostic codes on my engine?

Other ideas - possible clogged fuel filter? That thing hasn't been changed in forever... plus lowest fuel flow is at idle so that could be doing it. Air filter? Although I have been changing the air filter with every oil change... Ignition coil going back? I'm thinking NOT the fuel pump as at idle the demand on the fuel pump would be the lowest...

Ideas on what the problem could be? Or just more troubleshooting ideas?

 

Maybe a flaky ignition switch? That's not uncommon. When it shuts down, it doesn't display any warning lamps on the dashboard (just as if you had switched off the key).

When it's running (idling & parked), wiggle the ignition key. If you can get it to stall out this way, it's the ignition switch.

Unfortunately, if it doesn't stall out this way, that DOES NOT PROVE your ignition switch is good. Still, it's an easy painless check to do.

 

Most parts stores will scan your engine codes as a free service. Find out what code(s) you have, then post them on here. They start with the letter P and have four numbers, like P1234.

Do not blindly replace a sensor based on the code. The code will give you a place to start troubleshooting. A code can mean a sensor, wiring, the PCM, and other problems upstream could be the root of the problem.