I was driving this morning, running about 40mph when my engine quit without any prior indication. Running fine one second, dead the next except for the radio sounding out, and eventually the battery light as I coasted to a stop. I can crank it, but it won't start. There are no alarming or out-of-the-ordinary sounds while it cranks, and except for the radio, there were no sounds whatsoever during the failure. It's sitting in a public parking lot currently, and I haven't had a chance to do some backyard checks for fuel or fire issues, so I'm hoping for some insight where to begin aside from a few good squirts of ether to determine fire or fuel. The vehicle has 190,000 miles, so it could be anything, but it has run fine heretofore with nothing more than routine maintenance necessary, and I checked for the obvious stuff like unplugged vacuum hoses, unplugged or damaged wires, and I checked all the fuses and relays inside the power box.
Anyway, I did manage to scan the OBD, and I have a current code of P0420, and "continuous memory" codes of P0340, and P1116. Here is some background on the codes:
P0420 - (Cat/O2) "Check Engine" light has been on for about a month, but I've had this code several times during the last year, because of exhaust leak issues. This code was last cleared about 3 months ago when I had the exhaust fixed once and for all, though the light came back on the aforementioned month ago, about the same time my exhaust heat shroud started vibrating (not sure the two are related). Again, no "Check Engine" light for almost 2 moths prior, and this is the only "current" condition.
P1116 - (ECT sensor) Not sure what, during the last month or so that may have triggered this, but last summer I damaged the front end, and shortly thereafter the tranny reservoir leaked into the radiator. I fixed it by bypassing the tranny reservoir into a dedicated, external cooler. There is no discernible difference in the temperature of the engeine coolant before and after the repair. This is the first time this code has been recorded, and as mentioned above, it's a "continuous memory" code.
P0420 - (Cam Position Sensor) A good candidate for what happened today, but it's saved as a "continuous memory" code, but I suppose it could have occurred again today in grand fashion. I can't say there has been any "obvious" indication of a pending problem except that I've caught myself "wondering" for the last few weeks if I had a little less power during acceleration (again...wondering...not sure). I've also heard others describe a "chirping" noise the synchronizer shaft can make if it's suspect, and while I haven't heard such a noise, I have heard for about 15,000 miles (2 years) what I describe as a "ticking" noise...similar to a small stone stuck in the tread of a tire, or a plug wire shorting out, though neither condition ever existed, and I never determined the exact source of the sound.
Anyway, as I indicated above, as a first act, I plan on squirting some ether to see if it has spark, or isn't getting fuel. If it turns out to be a fuel-related problem, I'll work the problem from obvious points like filter and pump, then check online to see what else controls the fuel system sufficient to cause the shutdown I observed today. If it's an electrical problem...well...I'll perhaps start by replacing the Cam Position Sensor, and if that doesn't work...ask for a whole lot more advice!
Thanks for any advice or insights.
P.S. I was also wondering if this could be a timing belt issue? I've read where such a failure would have been obvious, and where one wouldn't have a clue except to look. Is there any way for one to easily determine if this is an issue without tearing down the engine, or any "tricks of the trade" one can use to determine same?