What is long term fuel trim and short term fuel trim?
Long-term fuel trim relies on sensors further downstream in the exhaust system, past the catalytic converter. While the sensors’ signal will fluctuate frequently upstream, where short-term fuel trim is measured, the signal at the sensors further down should be fairly constant.
What does the Check Engine light on Mercedes mean?
Mercedes-Benz owners may notice the check engine light plus P0170 and P0173 codes. In theory, these two codes mean that the fuel mixture is too rich or too lean.
What causes a fuel trim malfunction in a Mercedes?
Potential causes include a vacuum leak, unmetered air leaks Fuel saturated engine oil Leak in turbo air charge hoses (if equipped) Possibly bad O2 sensor (If Mercedes, may require adaptation with M-Benz compatible scan tool.) Oil contamination in MAF connector or O2 sensor connectors.
Why do I have two Mercedes Fault codes?
In theory, these two codes mean that the fuel mixture is too rich or too lean. Most of the time these Mercedes-Benz fault codes are caused by a defective Mercedes Mass Air Flow Sensor (MAF) sensor. You can try cleaning the sensor but that doesn’t always work.
What is the diagnostic code for fuel trim malfunction?
Cost of diagnosing the P0170 code. P0170 is a diagnostic trouble code (DTC) for “Fuel Trim Malfunction (Bank 1)”.
Mercedes-Benz owners may notice the check engine light plus P0170 and P0173 codes. In theory, these two codes mean that the fuel mixture is too rich or too lean.
Potential causes include a vacuum leak, unmetered air leaks Fuel saturated engine oil Leak in turbo air charge hoses (if equipped) Possibly bad O2 sensor (If Mercedes, may require adaptation with M-Benz compatible scan tool.) Oil contamination in MAF connector or O2 sensor connectors.
What is the OBD code for fuel trim?
Code P0170. Hi, thanks for writing in. The OBD-II Error Code P-0170 indicates that the powertrain control module is detecting a fuel trim that is outside the range of specification set by the vehicle’s manufacturer.
In theory, these two codes mean that the fuel mixture is too rich or too lean. Most of the time these Mercedes-Benz fault codes are caused by a defective Mercedes Mass Air Flow Sensor (MAF) sensor. You can try cleaning the sensor but that doesn’t always work.