[cromero1320]

Hello everyone! New to the BMW platform sorry for any stupid questions.

My girlfriend just purchased a 2019 330i with a check engine light because it does not have a catalytic. Her and her father do not like seeing the check engine light and the fumes from the exhaust with no catalytic. We are looking at just replacing the catalytic to get rid of the light and the smell. However after getting estimates for the labor to replace the cat we started looking at just getting the car tuned to remove the light. I would prefer to go with the tune to leave the nice downpipe and full exhaust the car has. She isn’t really worried about performance and getting the most HP, would a tune be able to remove the light and maybe adjust the air/fuel ratio to reduce the amount of fumes coming from the exhaust. We would appreciate any advise, thank you.

[zoso4534]

Problem #1 is you bought a car with a CEL.

I don't believe a tune is going to get rid of your CEL. You cannot pass inspection without a cat.

If you are concerned about the cost to put in a new cat, this might not be the car for you all.

[Bigslick2332]

A flash tune can eliminate the CEL but you would need to have your DME bench unlocked. A piggyback tune will not eliminate the CEL.

Sounds like you have a catless downpipe installed now which is why your smelling strong exhaust fumes. In order to eliminate that you would need to switch back to a catted downpipe.

You could probably find someone on this forum who is willing to sell you their factory downpipe.