Codes P2401 and P2099?

Here is what is said about the codes:

The error codes P2401 and P2099 on a 2004 Audi A4 correspond to specific issues related to the vehicle's emissions control system. Here's a breakdown of each code and its potential causes:

P2401 - Evaporative Emission System Leak Detection Pump Control Circuit Low:

This code indicates a potential issue with the control circuit of the evaporative emission system's leak detection pump. Possible causes may include a faulty leak detection pump, a wiring or connector problem in the circuit, or a problem with the power supply to the pump.
It is recommended to inspect the wiring and connectors associated with the leak detection pump for any signs of damage, corrosion, or loose connections. If no visible issues are found, further diagnostic testing may be necessary to identify the specific cause.

P2099 - Post Catalyst Fuel Trim System Too Rich Bank 2:

This code points to a problem with the fuel trim system on Bank 2 after the catalytic converter. Possible causes may include a malfunctioning oxygen sensor (O2 sensor) on Bank 2, a fuel delivery issue, a vacuum leak on Bank 2, or an exhaust system problem.
It is advisable to inspect the O2 sensor on Bank 2 and ensure it is functioning properly. If the sensor is old or has high mileage, it may require replacement. Additionally, checking for any vacuum leaks on Bank 2, inspecting the fuel delivery system, and examining the exhaust system for any leaks or damage may help identify and resolve the issue.

So, these are separate problems please start a new thread for the P2099 code. We will handle the P2401 code on this thread. It sounds like the leak detection pump is not working here is the location so you can change it out. Check out the images (below). Please let us know what happens.