You decided to clean your EGR valve to improve your car’s performance and reduce emissions. You followed the instructions carefully and reinstalled the valve. But when you tried to start your car, nothing happened. The engine did not even turn over. What went wrong? How can a simple cleaning job cause such a big problem? And more importantly, how can you fix it? Here we will explain the possible causes of why won’t a car start after cleaning EGR valve and how to troubleshoot and solve them. Don’t panic. You might get your car back on the road in no time.
Functions of The EGR Valve
The EGR valve redirects exhaust gases into the combustion chamber instead of discharging them into the environment. It controls the exhaust gas flow being recirculated depending on the engine load. This helps to reduce emissions, improve efficiency, and prevent engine knocking.
However, sometimes the EGR valve can malfunction or get clogged with carbon deposits, causing various problems for your car. One of these problems is that your car won’t start after cleaning the EGR valve. This is frustrating and confusing, especially if you are trying to improve your car’s performance by cleaning the valve.
Why Won’t a Car Start After Cleaning EGR Valve
Some of the possible causes of why your car won’t start after cleaning the EGR valve are
- Improper reinstallation of the valve or its components
You may have forgotten to tighten the bolts that hold the valve in place or reconnect the vacuum line or electrical connector. This can cause a vacuum leak or a wiring issue that prevents the valve from functioning properly.
- Damage to the valve or its components during cleaning
You may have accidentally sprayed some cleaning solution on the top part of the valve, which can damage the electrical parts. You may also have failed to test the valve for vacuum before reinstalling it, which can indicate a faulty valve.
- Carbon deposits pushed into the intake manifold or the cylinders
You may have scraped or vacuumed too hard and pushed some carbon deposits further into the intake system. This can cause a blockage or a foreign object in the combustion chamber, preventing the engine from turning over.
- Faulty sensor or wiring issue that affects the EGR valve position
You may have a bad sensor or a loose or broken wire that prevents the engine management system from correctly reading the EGR valve position. This can cause a check engine light or a lean air-fuel mixture, thus affecting engine performance.
Common Symptoms And Trouble Codes That Indicate a Faulty or Stuck EGR Valve
● Rough idle, hesitation, stalling, surging, or loss of power
● Poor fuel economy, increased emissions, or failed emission test
● Knocking, pinging, or rattling noises from the engine
● Check engine light is on or flashing
● Trouble codes related to the EGR system, such as P0401 (insufficient EGR flow), P0402 (excessive EGR flow), P0403 (EGR circuit malfunction), P0404 (EGR position sensor performance), P0405 (EGR position sensor circuit low), P0406 (EGR position sensor circuit high), P1404 (EGR closed position performance), P1406 (EGR pintle position circuit) and others.
If you see any of these symptoms or trouble codes after cleaning your EGR valve, you should test, diagnose, and fix your EGR valve soonest possible to avoid further damage to your engine. We will explain how to do that in the next section.
How to Tell if EGR Valve Is Working Properly
There are different ways to know if your EGR valve is working properly, depending on the type of valve and the symptoms you experience. Here are some common methods:
● Use a vacuum gauge or hand-held pump to test the EGR valve. Depending on the type of your EGR valve, you may need to apply a vacuum to the valve itself or the solenoid that controls it. The idea is to see if the valve holds the vacuum and opens and closes properly when the vacuum is applied or released.
● Use a scan tool or a multimeter to test the EGR valve. If you have an electronic EGR valve, you may need to use a scan tool or a multimeter to check the voltage and resistance of the valve and its components, such as the solenoid, sensor, and wiring. The objective is to find out if the valve and its components are within the specifications set by the manufacturer.
● Check for symptoms of a bad EGR valve: If the EGR valve is malfunctioning, you may notice symptoms such as rough idle, poor acceleration, knocking noises, check engine light on, or trouble codes related to the EGR system. These symptoms may indicate that your EGR valve is stuck open or closed, clogged, or damaged.
How to Test, Diagnose, And Fix a Faulty or Stuck EGR Valve
You need basic tools and skills to test, diagnose, and fix a faulty or stuck EGR valve. Here are some steps and tips on how to do it:
● First, locate the EGR valve in your engine compartment and disconnect the negative battery cable. Then, remove any sensors, electrical connections, and hoses attached to the valve. You may also need to remove the valve from the engine to access it better.
● Next, test the EGR valve with a vacuum gauge or hand-held pump. Depending on the type of your EGR valve, you may need to apply a vacuum to the valve itself or the solenoid that controls it. You can find the specific procedure for your vehicle in your repair manual or online.
● Inspect the EGR valve for any signs of damage or carbon buildup. If the valve is dirty or clogged, you can try to clean it with a suitable cleaner spray and a brush. If the valve is damaged or stuck, you might have to replace it with a new one.
● Finally, reinstall the EGR valve with a new or reusable gasket and reattach any sensors, electrical connections, and hoses you removed earlier. Reconnect the negative battery cable and start the engine. Check for any leaks or noises and test drive your car to see if there is any improvement in performance or emissions.
If the steps fail to solve your problem, you may have other issues in your EGR system, such as a faulty sensor, solenoid, vacuum hose, or passageway. You may have to use a scan tool or a multimeter to diagnose these components and check for trouble codes.
Alternative Solutions or Preventive Measures You Can Try Are:
● Use a good quality fuel injector cleaner or additive that can help dissolve carbon deposits and improve engine performance and emissions.
● Perform regular maintenance on your engine, such as changing the oil and filter, spark plugs, and air filter, to keep it running smoothly and efficiently.
● Avoid driving habits that can cause excessive carbon buildup, such as idling for long periods, driving short distances, or using low-quality fuel.
How do I clean an EGR valve?
Remove an EGR valve from the engine and spray it with a suitable cleaner spray, such as an EGR valve or carburetor cleaner. Use a dull scraper and a pipe cleaning brush to scrub off the carbon deposits from the valve. Try using a cotton swab or a soft brush to clean the shaft and port of the metering rod, which controls the gas flow. Wipe away any residue using a clean rag.
How do I Fix The EGR Valve?
To fix an EGR valve, replace it with a new one if it is damaged or stuck. The aim is to remove any sensors, electrical connections, and hoses attached to the valve, loosen the bolts that secure the valve to the engine, and remove the valve and the gasket. Then, install the new valve with a new or reusable gasket and reattach any sensors, electrical connections, and hoses you removed earlier.
How Often Should I Clean an EGR Valve?
There is no answer to how often you should clean an EGR valve, as it varies depending on factors, such as the type of valve, the engine’s condition, the fuel quality, and your driving habits. However, some general guidelines are:
● Read the owner’s manual for a maintenance plan, but you could inspect your EGR valve every 12,000 to 15,000 miles (19,000 to 24,000 km).
● If you see any symptoms of a bad EGR valve, such as rough idle, poor acceleration, knocking noises, or check engine light on, you should test and clean your EGR valve as soon as possible.
● You can clean your EGR valve every 20,000 miles or less to prevent carbon buildup and improve engine performance and emissions. Use good quality fuel injector cleaner or additive that can help dissolve carbon deposits.
● If your EGR valve is electronic, you may be unable to clean it without removing or damaging it. In that case, you may need to replace it with a new one if it fails.
Can an EGR Valve Cause The Engine Not to Start?
Yes, an EGR valve can cause the engine not to start. When an EGR valve gets stuck open, it lets air into the intake that the engine isn’t expecting. When that happens, there’s not enough fuel for the engine to burn, which can trigger starting problems. The oxygen coming through the EGR valve constantly changes when you start the car, and it’s hard for the engine computer to compensate for a bad EGR valve.
When an EGR valve gets stuck closed, it prevents exhaust gases from entering the intake manifold. That can cause pressure and heat buildup in the combustion chamber, leading to detonation and damage to engine components. The engine computer may also detect a problem with the EGR system and turn on the check engine light or store a trouble code.
The EGR valve helps to reduce NOx emissions and improve engine efficiency and fuel economy. Why won’t a car start after cleaning an EGR valve? if it gets clogged or stuck open or closed, it can cause starting problems. To prevent or fix these problems, you should regularly inspect, test, clean, or replace your EGR valve as part of your vehicle’s maintenance schedule. If you follow the steps and tips in this write-up, you will learn how to diagnose and fix an EGR valve that causes starting problems and save yourself some time and money.