Flashing CEL but runs smoothly

[protege3745]

Greetings,

I bought my 2003 Protg5 about 3 months ago, haven't driven it much due to an unfortunate Bambi incident though, so I'm about 1,000 miles in.

A few days ago, my CEL came on. It had been on before, but had gone away on its own as they often do, so I didn't think much of it. Then, after being on solid for a day, it began to flash. It flashes constantly with no pattern. From what I've read on here, all reports of flashing CELs are written of as "severe misfire, replace ignition coil". But I've had bad coils, and plug wires and various other misfires before and the misfire is always apparent. The engines especially didn't idle smoothly with bad coils, and they seemed to bog down a bit on my old Saturn. My Mazda is still running smoothly. No noises, no lumpy idle, no shakes, no quivers, nothing. If not for the flashing CEL you wouldn't think anything was wrong.

So my question is this; is there another common cause for the CEL to flash rather than stay on? Do these cars have severe misfires without exhibiting any of the typical symptoms? And the x-factor here, could driving through the recent extreme cold here in Minnesota without a grill (thanks Bambi) have fouled a sensor, causing the issue? Any ideas are welcome. This is my first Mazda and I've never owned a Japanese car before, just GM, Ford and SAAB.

Thanks

 

[esnave09]

Stop driving it! Anytime the CEL is flashing it means it's gonna be severe damage to your engine or emissions systems. Get the code read at Autozone or something. Bad coils aren't the only causes for the flashing CEL.

 

[Zixxer636]

Mine misfired because the head gasket/head cracked and cylinders 3 and 4 fill with coolant when you shut the car down. Could be anything but ya flashing cel is a misfire of some sort. Any other issues? Smoking, rough start?

 

[katapaltes]

I'm in a similar, but different situation. The CEL on my 2003 P5 came on a couple months ago (solid, not flashing), and the Torque Lite app showed a P0300 code. The car had no symptoms, however. I cleared the code because there were no symptoms and the car has been running normally since, and the CEL has not come back on. My valve cover gasket is leaking a tiny bit of oil, so I suppose that could be interfering with spark or something, but other than that, I can't find anything to fix. Should I worry about that CEL coming on in my case?

 

[lowlevel]

I'm in a similar, but different situation. The CEL on my 2003 P5 came on a couple months ago (solid, not flashing), and the Torque Lite app showed a P0300 code. The car had no symptoms, however. I cleared the code because there were no symptoms and the car has been running normally since, and the CEL has not come back on. My valve cover gasket is leaking a tiny bit of oil, so I suppose that could be interfering with spark or something, but other than that, I can't find anything to fix. Should I worry about that CEL coming on in my case?

You may have to just drive it until it gets a little worse/returns.... probably ok for now.