On both my '97 Taurus and '02 Impala, I have this mystery brown spotting appearing all over the interiors of both cars. It kind of looks like someone shook up a Coke and then opened it, or pulled a straw out of a coffee causing droplets to be sprayed around the interior. The spots are various sizes (as large as a dime and as small as a pencil tip). It’s mostly on the fabric - the seats and rugs, but I’ve also seen tiny specs on the dash. It always washes out of the fabric with Spot-Shot, and the dash blemishes wipe right off (they’re kind of guey like dried-up Coke would be), but it’s always been a mystery to me where these spots are coming from. Before I bought the '11 Equinox, the wife drove the '02 Impala and I was driving the Taurus. I wouldn’t see this spotting in my Taurus, but whenever I cleaned the Impala, I would see it in her car and so I’d ask her if she (or the kids) was spilling coffee or spraying colas around the interior. Answer was always “no”. Well, I had been doing work on my Taurus for several months and the car was just sitting all that time. Today I finally cleaned the interior of all the junk I was storing inside while working on the car, and I saw this spotting all over - on the carpeted mats, underneath the carpeted mats, and the seats (although not as pronounced).
Does anybody know what causes this? It just seems to appear on its own. Could it be an indication of coolant in the air? I’ve suspected both cars of having a heater core leak, but I don’t see any leaks in either interior. Could fumes be coming through the vents but not leaking/dripping on the interior? I can smell fumes of some kind in the Taurus, but not the Impala. I doubt coolant could be causing the stains, but I was thinking maybe it was acting kind of like the way law enforcement uses SuperGlue to fumigate and lift fingerprints, accenuating existing stains by contacting them in fume form.