Tried the reset while I was doing the plugs, no luck.
I spent a while chasing down a hissing noise about a year ago, but it never amounted to anything, however maybe this is what it was hiding all along. Admittedly it sounds really dumb to not have looked at this first, but I spent days looking for it last time (along with my mech) and we decided that it was nothing.
As for fault codes, I've got OBD2 and no scanner.
I guess tomorrow night i'll go hunting the hiss again...
thanks again everyone
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