What happens when the EGR valve is closed?
An EGR valve can fail in two ways: open or closed. The most common failure mode is failing closed when the vacuum diaphragm gets broken. When this happens, there are usually no adverse symptoms, only the engine can ping if it ran on regular gas. With premium fuel this will not happen.
Why is my Mercedes Benz starter not working?
Often times, when the starter is defective or seizes up it will blow out the fuse that protect the starter circuit. Another thing that you can try is to hit the starter with a rubber hammer a couple of times. Depending what kind of starter problems you have, the starter may work a few more times.
What to do when your EGR goes down?
Power goes down and fuel consumption drastically increases. This is because a lot of exhaust get sucked into the intake, diluting the fuel-air mixture. You need to remove the valve, clean the stem, test the vacuum diaphragm with a vacuum pump and go from there. Cleaning the EGR feed pipe will not accomplish anything. 1.
What are the symptoms of an inoperative EGR?
(If I add another $200, I will probably have a new cat at a road side mechanic) There are few indicators of inoperative EGR other than a failed emissions test for NOx. But in hot weather the engine may detonate under hard accell a little.
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.
What are the symptoms of a failing EGR valve?
What are the symptoms of a failing EGR valve? A faulty EGR valve can cause problems with the flow and operation of the EGR system leading to performance issues including a reduction in power, reduced acceleration and decreased fuel efficiency. It can also cause vehicle emissions to increase.
What should I do if my Mercedes Benz won’t start?
Start the car and you should be able to get around 60 psi. When the engine is running and when you turn off the engine the pressure should stay steady. Always perform this test on a cold engine. Next, make sure that the fuel injector connections are secure and not loose. Check the fuel pump and the fuel pump relay.
Can a vacuum be used to open an EGR valve?
A vacuum-operated EGR valve is usually only found in older vehicles. It is a straightforward system which utilises a vacuum to switch the EGR valve from closed to open. The vacuum is often regulated by a computer-controlled solenoid.