Check engine light codes P0170 and P0173 OBD2 on 1999 Mercedes Benz SUV

This is another easy fix on these OBD2 codes if you know what to do. These codes are tricky because they come in pairs. However, the 2 obd2 codes are the give away to the problem. To fix these codes is shown below.

Symptoms:

Check engine light is always on with obd2 codes P0170 and P0173 when scanned.

These are the meaning of these obd2 codes:

P0170 fuel trim malfunction
P0173 fuel mixture out of limits

Basic Concepts:

Both of these obd2 codes are a by product of possible air induction problem such as vacuum leak at intake manifold, defective fuel regulator failure and even a worn engine. You can test the vacuum leak by using ATS water spray method but the best approach in fixing this is to service the mass sensor. As you will probably know, this sensor is exposed to a lot of abuse if the regular air filter maintenance is not done on schedule. If this is the case with your vehicle, service the wire elements of the mass sensor using instructions found in ATS past newsletters and this should fix the problem.

Remember to reset the engine computer after servicing the mass sensor. Also, if the cost of the mass sensor is not too expensive, you can replace it outright. To locate the mass sensor, get hold of a MB service manual or contact ATS.