I have noticed that my Mitsubishi Fuso truck engine opens and closes intermittently the exhaust brake valve and emitting dark smoke coming from exhaust pipe without switching on and off the exhaust brake valve switch.This is commonly encountered during uphill at an speed of 20 to 40kph.sometimes this problem occurred when the engine temperature reaches 1/4 of the temperature gauge.
SOURCE: Mitsubishi Fuso Truck engine model 6M70 Intermittent opening and closing of exhaust valve.
this is an exhaust brake truck where the brake is in the exhaust manifold
the brake valve is actuated through a solenoid that controls the air pressure to the valve cylinder or the electric solenoid for the valve
it is operated either by the driver through a switch on the steering column or by a switch at the accelerator pedal where when the exhaust brake is switched on then with the accelerator pedal in the idle position it activates the actuator
there the problem will be in the switch at the base of the accelerator pedal, the switch in the dash or in the actuator itself
Testimonial: "thanks a lot bill for your immediate reply.do i need to undergo ECU scanning to locate where the fault coming from?I have already check the switch on the accelerator pedal and it is working properly so with the switch on the clutch pedal.Now the issue is even though i did not push the exhaust brake switch to on position at the steering column the exhaust brake opens and closes the exhaust brake valve as the engine temperature reaches around 1/4 of the temperature gauge."
Exhaust Gas Recirculation Circuit Range/Performance
What does that mean?
The EGR (Exhaust Gas Recirculation) system's purpose is to redirect exhaust gas back into the cylinders. Since exhaust gas is inert, it displaces oxygen and fuel, thereby lowering cylinder temps, which, in turn, lowers oxides of nitrogen emissions. For that reason it needs to be carefully metered into the cylinders (via the EGR valve) so as not to adversely affect the engine's performance. (Too much EGR and the engine won't idle).
FB.init("dd7d9e9681341cde77587bc6a2029f6f");
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If you have a P0404, then the EGR valve is likely an electrically controlled EGR valve instead of a vacuum controlled EGR valve. Also, the valve will usually have a feedback system built into it that informs the PCM (Powertrain Control Module) what position the valve is in; open, closed, or somewhere in between. The PCM needs to know this to determine whether or not the valve is operating as needed. If the PCM determines that the valve should be operating, but the feedback circuit shows that the valve is not open, this code will set. Or if the PCM determines the valve should be closed but the feedback signal indicates that the valve is open, this code will set.
Symptoms
There may be no symptoms of a P0404 DTC other than the MIL (malfunction indicator lamp) or check engine light. However, Exhaust Gas Recirculation systems are inherently problematic due to carbon buildup in the intake manifold, etc. This normal buildup can lodge in an EGR valve, holding it open when it should be closed. If this is the case, the engine may idle rough, or not at all. If the valve has failed and is NOT opening, then symptoms would be higher combustion temps and as a result, higher Nox emissions. But the latter symptoms aren't going to be noticeable to a driver.
Causes
Usually this code points to either carbon buildup or a bad EGR valve. However that doesn't rule out the following:
Exhaust Gas Recirculation Circuit Range/Performance
What does that mean?
The EGR (Exhaust Gas Recirculation) system's purpose is to redirect exhaust gas back into the cylinders. Since exhaust gas is inert, it displaces oxygen and fuel, thereby lowering cylinder temps, which, in turn, lowers oxides of nitrogen emissions. For that reason it needs to be carefully metered into the cylinders (via the EGR valve) so as not to adversely affect the engine's performance. (Too much EGR and the engine won't idle).
FB.init("dd7d9e9681341cde77587bc6a2029f6f");
OBD-Codes.com on Facebook
If you have a P0404, then the EGR valve is likely an electrically controlled EGR valve instead of a vacuum controlled EGR valve. Also, the valve will usually have a feedback system built into it that informs the PCM (Powertrain Control Module) what position the valve is in; open, closed, or somewhere in between. The PCM needs to know this to determine whether or not the valve is operating as needed. If the PCM determines that the valve should be operating, but the feedback circuit shows that the valve is not open, this code will set. Or if the PCM determines the valve should be closed but the feedback signal indicates that the valve is open, this code will set.
Symptoms
There may be no symptoms of a P0404 DTC other than the MIL (malfunction indicator lamp) or check engine light. However, Exhaust Gas Recirculation systems are inherently problematic due to carbon buildup in the intake manifold, etc. This normal buildup can lodge in an EGR valve, holding it open when it should be closed. If this is the case, the engine may idle rough, or not at all. If the valve has failed and is NOT opening, then symptoms would be higher combustion temps and as a result, higher Nox emissions. But the latter symptoms aren't going to be noticeable to a driver.
Causes
Usually this code points to either carbon buildup or a bad EGR valve. However that doesn't rule out the following:
Exhaust Gas Recirculation Circuit Range/Performance
What does that mean?The EGR (Exhaust Gas Recirculation) system's purpose is to redirect exhaust gas back into the cylinders. Since exhaust gas is inert, it displaces oxygen and fuel, thereby lowering cylinder temps, which, in turn, lowers oxides of nitrogen emissions. For that reason it needs to be carefully metered into the cylinders (via the EGR valve) so as not to adversely affect the engine's performance. (Too much EGR and the engine won't idle).
If you have a P0404, then the EGR valve is likely an electrically controlled EGR valve instead of a vacuum controlled EGR valve. Also, the valve will usually have a feedback system built into it that informs the PCM (Powertrain Control Module) what position the valve is in; open, closed, or somewhere in between. The PCM needs to know this to determine whether or not the valve is operating as needed. If the PCM determines that the valve should be operating, but the feedback circuit shows that the valve is not open, this code will set. Or if the PCM determines the valve should be closed but the feedback signal indicates that the valve is open, this code will set.
SymptomsThere may be no symptoms of a P0404 DTC other than the MIL (malfunction indicator lamp) or check engine light. However, Exhaust Gas Recirculation systems are inherently problematic due to carbon buildup in the intake manifold, etc. This normal buildup can lodge in an EGR valve, holding it open when it should be closed. If this is the case, the engine may idle rough, or not at all. If the valve has failed and is NOT opening, then symptoms would be higher combustion temps and as a result, higher Nox emissions. But the latter symptoms aren't going to be noticeable to a driver.
CausesUsually this code points to either carbon buildup or a bad EGR valve. However that doesn't rule out the following:
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