Originally Posted by Focused Fordster
although this may sound too late, but have you had a similar experience to mine after switching from Ford Focus original fuel cap with no lock into one with a lock: the Check Engine / Check Fuel Cap lights remain on all the time now that i have a lockable fuel cap!
there IS a solution to that but it won't work forever: i can reset the car's computer by unplugging the wires from the battery, and the two mentioned lights will go off, but the problem is that they'll go back on again after a couple of days!
is there any solution out there so that i could still keep the lockable cap in place instead of the original? (i still have the original fuel cap btw. could i take something out from that one and put inside the lockable cap for example? how does the car's computer recognize the original cap is missing: is there some special 'sensor' or anything inside the original fuel cap?)
any feedback by anyone would be highly appreciated!
my car: Ford Focus ZX5 2005
I bought my son a locking gas cap for his '07 Focus. He had the same problem. I put a film of motor oil on the gasket (same thing you would do on an oil filter gasket). The problem went away. I'm guessing the gasket on the cap was just dried out and wouldn't seal. Armorall or similar may work as well.