Hi.

I've got a '97 Grand Caravan 3.3l w/160k miles which I've owned for about six months. I haven't had any issues/problems with it, but then in the last 24 hours the following "weird" things have occurred:

1) My turn signals & emergency flashers quit working. Though I was planning to pull the signal relay to check it, the problem went away and didn't come back (I've put about 75 miles on the van, various start/stops & everything is working fine).

2) Threw a "Service Engine Soon" warning w/code P0420. The light came on when I slowed to ~30mph, after a 20 minute highway drive at ~60mph. The only "out of the ordinary" thing I've done recently is fill the tank today at a "so-so" gas station (the tank was almost empty). Though I normally tighten the gas cap 'til it clicks, I did go ahead and re-tighten it after the code appeared.

Is there a snow-*****' chance these two things are electrically related? I don't see how they could be...PCM is engine control, intermittent turn signals is a relay/fuse box problem. But since both issues occurred in close proximity to each other, I thought I'd ask. Also, can a loose gas cap or cruddy gas cause a P0420? I know that code almost always results in a cat replacement, but I haven't noticed any rough idle, loss of power or hesitation issues; I also passed an emissions test in September.

Thanks for any help!

M_C

 

And one other thing: I also got a 12 MIL code...even though I haven't disconnected the battery within the last 50 key-on cycles.

 

Yes bad gas can be a problem with any car. No the gas cap will give a evap code like P455. o2 sensor can also give you the P0420 code too.

 

my sources say 255 key cycles for 12 to disappear but still who cares, it lets you know that the diagnostic system is starting up and working