LFA check engine light exhaust fumes

Greetings. The confluence of the check engine light, stored error codes, and observed exhaust leak suggests a potential malfunction within the NOx sensor system. Have you inspected the cable and plug connection of the component for any signs of degradation or displacement? It is imperative to ascertain the integrity of these connections prior to further diagnostic procedures, as a defective cable or plug can mimic sensor failure.

Thanks for the insight! When you say 'integrity of connections', what exactly should I be looking for? I'm not exactly a mechanic, just trying to avoid a costly workshop visit if it's something simple.

Acknowledged. By 'integrity of connections,' I refer to a meticulous examination of the cable and plug associated with the NOx sensor. Scrutinize the cable for any breaches in the insulation, corrosion, or physical damage. Similarly, the plug should be assessed for secure attachment, absence of corrosion on the pins, and overall structural soundness. If the aforementioned issue is not the cause, I must suggest that you seek professional assistance for accurate error diagnosis. It seems like it is a sensor issue, which could be a pollution control issue.

Took your advice and checked those connections. Couldn't see anything obvious, so bit the bullet and went to the shop. Turns out you were spot on – it WAS the NOx sensor. They replaced it, and the light's gone. Bill came to 95€, not as bad as I feared. Thanks again for the help!