The A4's with the gas cap light have magnets inside the gas cap, did you just purchase this audi recently or get the gas cap replaced? If you get the wrong gas cap it will trip the light (no faults), it should feel kinda heavier than a regular cap, 9 times out of 10 the problem is the gas cap.

 

I did just buy this a4 a few months ago. However, I believe it is the correct gas cap. It is a bit heavier than normal and is labeled as a VW/Audi part. Is there anyway to test this?

 

Un-fortunately no, we usually just swap out caps from other A4's in the shop and the light usually turns off. I have yet to find a car with a faulty cluster/wiring for this issue, the sensor justs picks up the magnet so there really isn't any contact to break.

 

Ill have to try a new that then...thanks for the info...I'm not seeing any kind of sensor inside the opening though...All i see is a little wire hook that sticks out...

 

Thats it, all the magnet does is complete the circuit, thats why its never gonna be sensor. One single wire to the instrument cluster tells the instrument cluster whether the gas cap is there or not, make sure you get the correct cap!!!

 

Thanks for the help auditech! After playing with the gas cap and a magnet I came up with a somewhat cheaper solution that bypassed that sensor. I was able to fit a small magnet in between the filler nozzle and the black sensor on the right side. This completed the circuit and made the light go out. Might be a little bit of ghetto enginering but it works.

 

Hey Guys, Sorry for resurrecting this old post but i've tried what macbeck22 did to stop my stupid gas cap light from flashing and it just wont.[&:] It's been flashing for bout 3 weeks now and is so annoying since everytime i open a door or sometimes just randomly while driving the light flashes then i have to hit the button on the stalk again.[:@] Is there anyway to just disable it using vagcom or twisting 2 wires together? That is is sooo annoying. [:@]

 

I have an A4 that has both the check engine light and the gas cap light are on. Very disturbing. Nothing wrong with the cap. Occasionally it will go off, but comes back on. One mechanic told me it was the worm drive that locks the flap that needed replaced.... $250+. I will check the cap but have had the car for years and its never been on before. Also the check engine light... Doesn't need oil change. And was just serviced so fluids should be ok. They both will flash at times the engine one when I go over about 50.

Any help you can give would be great. Thanks.

 

There's basically a small wire around where the fill hole is. If this sensor doesn't get connectivity through the magnet in the gas cap it will trip the sensor. You can try pulling this small wire up to improve connection, but if that doesn't work you might have to replace the whole filler neck.

Also - when you can't get the fuel nozzle out of the filler neck, lift up on the handle of the fuel nozzle and out. If you just try pulling straight out you will ruin the filler neck.

Jason

 

Hi, my car has the same issue and i remember that metal sticking out.


Ill go downstairs and fix it right away. ill take a picture too

And here is fixed:


I have to tell you, IT WORKED!!!
the light wet away ))
I have 2003 Aud A4 3.0 convertible

And how did i fix it?
it was because at one point someone didnt look carefully when he unplugged the hose after filling up with gas. and it bent the lower part of the housing. i saw that piece of aluminum sticking out, but didn't think is a big deal. well, IT WAS.
took a screwdriver and a hammer and in 3 minutes all was looking pretty. and no light!!!