Check Engine Light Due to Gas Cap Issue on Cadillac DeVille

Illumination of the Check Engine Light may be the result of a loose or worn gas cap.

RepairPal Verified
Average mileage: 97,516 (25,500–194,000)
9 model years affected: 1996, 1997, 1999, 2000, more2001, 2002, 2003, 2004, 2005
48 people reported this problem
21 people shared problem details
Code came up with very small vacuum leak in evaporator system or also Check Gas Cap. I originally fixed the problem by dabbing a small amount of grease on the rim of the gas filler neck. But after a year or so I finally figured out the problem. The gas cap is a poor design. I tore apart the gas cap and found out the seal that is really a like a rubber grommet does not contact the rim of the filler neck properly. I took a piece of single strand copper wire and wrapped it around the back side of the seal (side closest to the handle of the cap) forcing the seal closer to the rim side of the filler neck. Problem solved. RRH
2000 Cadillac DeVille194,000
check gas cap comes on on the dash replaced cap 3 times still comes on have reset computer everytime
Dealer wanted $79.50 for a new cap. Autozone $12.00
2005 Cadillac DeVille125,000
I got the warning. I took the gas cap off, cleaned it and applied some light silicon lubricant and the problem hasn't come back in a couple of years now. I did NOT replace the cap... just cleaned it.
2002 Cadillac DeVille110,000
I have replaced the gas cap twice without eliminating the problem
2004 Cadillac DeVille145,000
I replaced the gas cap and it is still and issues. I suspect there is a vacuum leak somewhere around the gas tank.
Gas cap causes sensor to trigger the service light. Small vac leak. and as everyone know the heads are leaky but i love her ;) lol called the dealer $35 for a new gas cap with the factory harness 99 for the win!
Service engine light on and evap code. Both (99,400 and 14,300)times resolved with new cap. Seems like cap should last longer.
2005 Cadillac DeVille100,000
Not fixed, needs new gas cap, needs so much stuff, this is small.
replaced cap multiple times from dealer. finally they must have felt sorry for me and told me to clean the cap really well...toothbrush & water...dry well with lint free cloth. It worked!!! have to do about every six months as error codes starts again. Still doing @ 102,000 miles...looks like they would have fixed this by now!!!!!
Service Engine Soon Light came on. Reseated the cap many times. Changed fuel brands and used 3 additional tanks of fuel. Dealer said the seal in the cap goes bad and they do not sell a replacement seal. New cap solved the problem immediately.
i have had these code off and on for about an year and i keep like a fool replacing the cap and the problem never goes away until it just wants to. i do not know why it does it but it comes and goes and no one knows why.
2003 Cadillac DeVille120,000
My faulty cap was replace 3 times. Engine light goes off then back on. Seems like this should be a recalled item. Using the same faulty cap over and over does not solve the problem. My mechanic informed me that Cadillac Deville 2003 has pages and pages of recalled parts. When I asked Cadillac about this they said my recalls were closed. I interpreted that to mean they cannot afford to keep replacing recalled parts with more faulty parts. Done with Cadillac! Have spent thousands and thousands on maintenance including a transmission rebuild, and now most recently oil leak and coolant leak...sheesh!
appears that after it rains the Check Gas Cap sensor goes on.. Thinking it's a Sensor issue
2005 Cadillac DeVille104,000
Tightened gas cap and the light eventually went off.
2004 Cadillac DeVille120,000
Problem not yet resolved. Will probably have to replace cap
2002 Cadillac DeVille110,000
had to buy new fuel cap. then had to wait two days for sensor to register the new fuel had been installed before light went off.
Check Gas Cap displayed on 'info'. Tried tightening cap several times, light came back as soon as I started the engine. Saw on another forum that the cap may need replacing...will attempt that as the first option.
Related Items:
check engine light on code po443 evap emission system purge vent soleniod circuit condition. wh...
replaced evap soleniod near gas tank and the one on the intake also replaced gas cap. cleared...
An intake manifold vacuum leak can develop from a variety of sources, often causing illuminatio...
Two likely causes for the Check Engine Light to illuminate would be a loose or worn gas cap or...
the car quit had to replace the whole fuel pump. since then the service engine light is on. i h...

Related Content