What do you need to know about the EGR valve?
The EGR valve is a small component designed to allow the flow of exhaust gases into the intake manifold in controlled amounts. As such, it’s a simple valve that closes and opens as needed.
Which is the correct formula for EGR error?
The EGR Error is also normalized for all types of EGR systems. The reading is based on a simple formula: (Actual EGR Position − Commanded EGR) ÷ Commanded EGR = EGR Error. For example, if the EGR valve is commanded open 10% and the EGR valve moves only 5% (5% − 10%) ÷ 10% = −50% error.
How is exhaust gas recirculation ( EGR ) used in diesel engines?
Means of adjusting the residual gas fraction generally rely on mechanisms such as two-stage cam-lift, camshaft phasing, variable valve actuation, and fully variable valve actuation. EGR (external) is the main technology used by vehicle manufacturers for the reduction of NOx emissions on diesel engines.
Why does my EGR valve keep sticking open?
Eventually, this will affect the valve’s plunger mechanism as well, causing it to stick open or close. On top of that, EGR parts and components wear out and stop functioning properly. That’s when troubleshooting becomes necessary.
These systems are mostly comprised of the EGR valve, a DPFE (Delta Pressure Feedback EGR) sensor, hoses, a vacuum regulator, some vacuum lines, wiring, the computer and the exhaust tube leading to the valve itself.
When does the Check Engine light come on on an EGR?
Check Engine Light comes on. An illuminated Check Engine Light is another symptom of a bad or failing EGR control solenoid. If the computer detects an issue with the EGR solenoid, circuit, or system, it will set off the Check Engine Light to notify the driver of the issue.
Why does my dpfe have a leaking EGR valve?
You now know the DPFE, EGR valve and tube and hoses are okay and we can move on to test the EVR (EGR Vacuum Regulator), part of the system. If the reading did not change, then you could suspect a leaking EGR valve, allowing uncommanded flow of exhaust gases.
Why is my EGR valve stuck in the open position?
One of the most common symptoms of a problem with the vehicle’s EGR valve is a rough idle. It is not uncommon for EGR valves to malfunction and become stuck in the open position. This can lead to exhaust gas recirculation, which causes rough idling even when the conditions are not desirable.
Where are the EGR Jets in the intake manifold?
A more radical design, implemented in a few models, was the replacement of the valve with EGR jets at the bottom of the intake manifold. Some newer high-efficiency engines, for example those with variable valve timing (VVT), don’t even use an EGR system. If playback doesn’t begin shortly, try restarting your device.
How does EGR reduce the production of NOx?
To reduce the amount of NOx pollutant emitted from your vehicle, exhaust gases need to be cooled before being emitted from your vehicle. In order to achieve this, they are introduced back into the combustion chamber via the exhaust gas recirculation (EGR) valve; this reduces the temperature and thereby inhibits the production of NOx emissions.
Why does my engine stall when the EGR is open?
This is because the temperature is lower so fuel does not burn at the optimal temperature and as a result is less efficient. Stalling when the engine idles like a rough idle is usually caused when the EGR valve is permanently open and is constantly letting exhaust gases into the EGR system.
Are there any disadvantages to using an EGR valve?
There are some disadvantages of EGR as well such as loss in fuel economy, low performance and, in diesel-engine cars, the production of soot increases. However, modern engines use clever technologies for an efficient process, for example, new diesel engines now use EGR cooler which cools down the exhaust gasses by passing the coolant.
When to replace the EGR valve on a diesel engine?
The EGR valve on a diesel engine usually gets a lot more dirt in it, and it has to be replaced and cleaned more often. The carbon build up can also destroy the EGR valve and you have to replace it more often. A lot of people, reprogram the EGR valve to not function to reduce the amount of carbon build up in the engine.
How many EGR valves does a Jetta have?
There are just too many to list…. Disregard the statement about your fuel filter, that has nothing at all to do with your problem. There are TWO EGR valves on your car, two completely independent systems, a high pressure and low pressure.
How does EGR work in a CR car?
It is an EGR regulating valve. Bosch has some excellent textbooks on modern EDC systems that cover EGR in great detail. When this flap closes, it forces more EGR through the open EGR valve, and speeds up the velocity of the incoming EGR flow. PDs do this, too. Just that the CR cars have another, completely separate, EGR system.