A few weeks ago I had an issue where the little strap that holds the gas cap on was obstructing the cap from sealing. It took the check engine light nearly 2 weeks before it turned off.
I thought this was the reason. I checked the cap closely and there was no damage.
Now it’s back on again approximately two weeks later.
when I check the systems it says “all systems OK”
this happened a year ago when it was under warranty.
dealer is telling me it’s $160 just to do the diagnosis.
anyone else have a similar issue?
Thanks

 

Check engine light will illuminate when there is any OBDII error code present, not exclusively when there is an air gap in the gas cap. So it's impossible to to tell the exact reason without reading those codes.
In order to read codes you need to have a code reader, or bluetooth/WiFi OBDII adapter + mobile app.

 

i’m aware of that. What I’m asking is: are false Engine lights a known issue?

 

I would assume the answer to be “no”. Get the codes, and go from there.

 

Agreed with @njaremka - I've never heard of false CEL. Granted the severity of reason might vary, but I personally would be very uncomfortable driving with CEL on without knowing the code that caused it.
Just last week CEL came up for me with P0302 (cylinder 2 misfire) code. A bit of additional diagnostics revealed faulty ignition coil. Replaced coils, reset the light and it's all good now. The best thing is I feel confident I have addressed the actual issue, not just rolled the dice with my best guess.
Code readers are very affordable and one time investment (unless you go with app subscription options), but since they provide such a valuable insight into car issues they really worth it.
As @chefjoseph mentioned a single visit to dealership can cost at least as much or even more (depending on the reader).

 

https://www.foxwelltool.com/wholesal...installed.html


pretty decent scanner with the BMW/MINI special load ... you can also use it to register a new battery and stuff .....

BUT as mentioned in a different thread recently it will tell you the code and let you clear some. Details about what the code MEANS and specifically how to fix it are NOT what this diagnostic tool is gonna do . . .

 

I ordered an "In stock" BlueDriver Bluetooth Pro from Amazon nearly 2 days ago and they have been unable to supply me with a shipping date !? WTF?? I am thinking of cancelling if I don't hear from them soon.

A few months back I had this issue (under warranty) with no explanation from my SA other than it was a "known issue".

 

I have a friend who has a scanner and he was able to ascertain the problem. According to his OBD2 scanner,
it’s the gas cap… again.
Now I don’t have to pay BMW.
Hopefully that’s all it is. I will try replacing the gas cap.

 

Glad you were able to confirm the reason! Maybe you can just replace the gasket instead of entire gas cap?

 

The last time it took two weeks before the check engine light turned off, now it’s been on nearly 2 weeks… again.
The gasket you were referring to looks like it’s actually part of the cap. For $25, I’d rather replace the cap. Could there be a leak elsewhere in the system?
(Code was: P0456)