Some models may have a problem where the Check Engine light illuminates indicating an improperly tightened fuel cap. Due to improperly manufactured threads on the fuel filler pipe, the filler pipe may need to be replaced.Google+
Car Problem Reports
Mazda Miata MX-5 Check Engine Light Due to Improperly Manufactured Threads on Fuel Filler Pipe
Mazda Miata MX-5 Problem
Average Mileage: 41,819 mi (8,444 mi - 145,000 mi)
Visitor, 2006 Mazda Miata MX-5, 29,605 mi
check engine light comes on. Dealer Service shows problems with fuel filler pipe but this vin# not included in recall. Why?
Visitor, 2012 Mazda Miata MX-5, 16,500 mi
CEL comes on
Gas cap comes loose
Visitor, 2006 Mazda Miata MX-5, 61,500 mi
Check engine light on
Visitor, 2006 Mazda Miata MX-5, 24,030 mi
Repeated check engine lights after fueling vehicle and tighening gas cap.
Visitor, 2010 Mazda Miata MX-5, 8,444 mi
Taken the car in to the dealership 3xs. They continue to maintain that the light is on because I am not "tightening the gas cap enough"! I KNOW how to tighten a gas cap!! Today I was humiliated while the service consultant explained that "if" I am telling them the truth, they will do me a "favor" by replacing the gas cap, because it is clearly the owner's mistake and not theirs! Grrrrrr
Visitor, 1999 Mazda Miata MX-5, 145,000 mi
I have not fixed the problem, but every time I fill up the gas tank, the check engine light comes on. Once the fuel level drops below 1/4 tank it goes away.