P0191 Audi Variant OBD Code

OBD/2 P0191 error code description and symptoms.

Low Speed Fuel Pump Primary Circuit Malfunction The PCM monitors the low speed fuel pump (LFP) primary circuit output from the PCM.
The test fails if: When the LFP circuit is commanded on (grounded), excessive current draw is detected on the LFP circuit; or when the LFP circuit is commanded off, voltage is not detected on the LFP circuit (the PCM expects to detect VPWR voltage coming through the low speed fuel pump relay coil to the LFP circuit). Open or shorted low fuel pump (LFP) circuit Open VPWR to low speed fuel pump relay Damaged low speed fuel pump relay Damaged PCM An open circuit or short to ground can only be detected with the low speed fuel pump.

As long as the throttle plate remains closed, the idling speed and quality is controlled by the PCM via the idle control valve, and as can be seen from the above it should be clear that idle control on a gasoline engine is a complex affair. For instance, if the engine is started in sub-zero temperatures, the PCM will command the idling control valve to allow less air to enter the engine to enrich the air/fuel mixture to create a condition which is roughly analogous to how chokes worked on carburetted engines to control idling in cold weather.

P0191 Audi Variant Error Code Repair Process :

If your vehicle failed a P0191 test and the P0191 Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses p0191 fuel rail pressure sensor circuit range/performance a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look p0191 fuel rail pressure sensor circuit range/performance: Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression. Use your OBD Express DIY to look at the oxygen sensor outputs, coolant temperature, airflow, calculated engine load, and inlet air temperature.

Common Causes of Audi Variant P0191 OBD2 Code

A common cause of code P0191 is the failure of P0191 Fuel Rail Pressure Sensor Circuit Range/Performance, but there are several other possible causes as well, such as ;

EVAP canister or fuel tank leaks
1Camshaft Position Sensor circuit poor electrical connection
Ignition coils circuit poor electrical connection
Faulty Air Flow Meter

P0191 is a kind of Powertrain Trouble Code

Powertrain of a modern automobile, comprising engine (with exhaust system), transmission, drive shaft, suspension and the wheels. In a motor vehicle, the term powertrain or powerplant describes the main components that generate power and deliver it to the road surface, water, or air.

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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P0191 Audi Variant OBD Code

P0191 Audi Variant Error Code Repair Process :

Common Causes of Audi Variant P0191 OBD2 Code

P0191 code for other Audi cars