Check Engine Light Due to Improperly Manufactured Threads on Fuel Filler Pipe on Mazda Miata MX-5

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.

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Average mileage: 36,826 (4,000–145,000)
9 model years affected: 1994, 1999, 2006, 2007, more2008, 2009, 2010, 2012, 2014
24 people reported this problem
13 people shared problem details
check engine light comes on. Dealer Service shows problems with fuel filler pipe but this vin# not included in recall. Why?
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CEL comes on Gas cap comes loose
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Starting when I bought this car used with 37000 miles on it I get a check engine light the code set is a loose gas cap and has now occurred 3 times in the last 9000 miles. I know that the cap has been reinstalled properly after refueling and I have to bring the car to my mechanic to reset the engine light, the cap is loose when the light comes on.
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Check engine light has been on now for several weeks. I went to a parts store and ordered a new gas cap. Put the new gas cap on and CEL is still on. Next step is to go purchase a gas cap from the MAZDA dealership.
Happened twice, dealer replaced fuel cap, then a sensor in the trunk.
When I fill up I have to reseat the gas cap and the light still stays on
got code p0442 and replaced fuel cap with new redesigned mazda one. light stayed off for 100 mile and came on again. cap was loose. dealer will not fix.
Check engine light came on. The code read by the service center pointed to the fuel filler cap. It was replaced and the problem went away.
engine light comes on and stays on, the fuel filler cap is loose, I tighten it and in a few days it comes loose again all on its own.
Check engine light on
Repeated check engine lights after fueling vehicle and tighening gas cap.
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
1999 Mazda Miata MX-5145,000
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.
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It only has 19000 miles on it. In addition, it needed an O2 sensor and a tuneup including a engine ignition coil.

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