U1755 Diagnostic Trouble Code

U1755 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a U1755 diagnostic trouble code may include:

Misfire
Misfire
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly

Possible Causes :

A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.
Faulty IMRC actuator/sensor
An air leak forward of the DPF will change the sensor readings resulting in the code

Repair Processes :

Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed. It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem. Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness.

Process Tips

Diagnostic trouble code U1755 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before U1755.

Fortunately, U1755 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U1755 Trouble Code For Specific Cars

U1755 Rolls-royce Silver Spirit Idle Air Control Circuit Malfunction
U1755 Gilbern Gt Oil Level Lamp Circuit Open
U1755 Lincoln 47 Hp Throttle Position (TP) Sensor Circuit Intermittent High Voltage
U1755 Mitsubishi Gto Autolamp On Circuit Open
U1755 Mercury Grand Marquis Air Suspension LR Corner Up Timeout
U1755 Ginetta G12 Oil Level Switch Circuit Short To Battery
U1755 Chery A13 Door Unlock Disarm Switch Circuit Short To Ground