Gas Cap Question...

[Airman84]

I posted this in the GENERAL forum by accident so I am posting my question in the TECHNICAL forum. I am designing a military gas cap to fit on to the H3/H3T. I was wondering if there is anyway around the "check engine light" that comes on if the cap is off. Is the light only coming on because it needs a constant seal or is there something in the factory cap that prevents the light from coming on when it is properly attached? The dealer, ofcourse, is telling me that there is no-way around the light. I should be able to get a good seal, the caps I'm using were taken off... literally taken off... of military aircraft that have been used/flown for over 30+ years! FYI... I have them because they were removed from the aircraft for an upgraded model... no theft! lol. I will have pictures soon and once I get the design working without problems I will be more than happy to make acouple extras to those who would like one. Thanks!