EGR valve?

Question

I was told that my 2004 caravan needs a new egr valve. Is this something that needs to be fixed immediately? Or can it wait for awhile?

What is an emmisions test?

Answer 1

Exhaust Gas Recirculation or EGR is employed in Diesel engines and in direct injection gasoline engines to reduce the NOx emissions. For homogeneous charge burning engines (carburetter engines) and in port injection engines a three way catalyst contained in the catalytic converter takes care of NOx and CO emissions reduction. Higher quantities of NOx is produced if the combustion temperatures in the engine are high. Recirculation of some amount of exhaust gas reduces the peak temperatures and thus reduces NOx formation. Larger quantity of EGR will impair the performance of both gas as well as diesel engines.
Yes, it needs to be fixed if you are going for an emission test.

The exhaust from your car contains harmful components like Carbon monoxide (CO), Oxides of Nitrogen (NOx) and unburnt hydrocarbons. These are called emissions from automobiles. In view of protecting environment and human beings from the harmful effects of these gases most countries have passed legislations restricting their concentration in the car exhaust. The vehicles are tested by DMV to check whether the emissions are within specified ranges. This test is known as emission test.

Answer 2

The EGR valve or Exhaust Gas Recirculation valve is located on the exhaust system. These typically get hung up with rust and other exhaust deposits. The vehicle may be under factory warranty being only 3 years old. I'd check with a dealer to see if the vehicle and/or part is still under warranty. A defective EGR valve will cause the computer to make the wrong settings to the fuel and air mixture causing the engine to run too rich or too lean. Its not too damaging in the short term, but your gas mielage will suffer, and you may fail a state inspection so get it repaired before then.

Answer 3

Txpilot is correct. As long as your van starts and runs normally your fine. If the valve ever gets stuck in the full open mode the motor will not idol at all. If stuck open you'll have a slim chance of even getting it started! To prove this, have someone (mechanically inclined) reach behind the valve and gently squeeze the bellows toward the top of the valve facing you. You'll note that the motor starts to stumble and quits in a dime. Release the bellows and start the motor. It'll run fine. Put this on your to do list as it most likely will not pass the "tube" test without a functioning EGR ( exhaust gas recirculation) valve.

Answer 4

I'll tell you this, my check engine light has been on for months and I believe it is my EGR valve. The car runs okay, except for some rough idling. I would fix it, but I don't have the right wrench.
If it breaks completely then yes, it obviously needs to be changed immediately. It could cause a vacuum leak and the car could not start. If it is a minor problem, I wouldn't worry about it, especially if your service engine soon light isn't on. It will be expensive, I warn you. I bought an EGR valve for about 100 dollars for my car.

Answer 5

EGR valve reroutes hot fumes into inlet manifold to heatup fuel-air mixture, so the fuel can evaporize easier thus producing better mixture and burn faster, so EGR is helpful, you should get it working either by cleaning EGR channels or replacing the valve. The only exception is when engine runs on LPG (propane gas) which vaporise very quick and mix with air perfectly, so recirculating exhaust back the engine is pointless in this case, and even kills the performance. EGR should be disabled when running on LPG.

Answer 6

EGR = exhaust gas recirculation valve

So, when your car isn't idling or cold, the EGR valve will take some of your exhaust gas and pump it back through the engine (mixed with air). This reduces the emission of Carbon Monoxide in your exhaust. The reason this doesn't happen when idling or cold is it can cause knocking.

So, your car will work fine with it "broken", but you won't pass your next emissions test.

Answer 7

The EGR valve is vacuum operated and usually gets clogged with carbon deposits. They may be cleaned with a spray chemical available at the parts store. If clogged, they generally cause rough idle and poor performance, but will not ruin the engine.

Answer 8

EGR = exhaust gas recirculation; meaning your car exhaust is run back through the engine, because most cars don't fully burn all the gasoline the first time around and so re-burning it improves your fuel economy. It's like flattening your toothpaste tube to squeeze all the toothpaste, versus mashing the tube in the middle and leaving all that trapped unused toothpaste.
it's not that expensive to fix. why are you wanting to wait? your minivan is probably running lousy and your fuel economy has taken a nose dive, right? with gas back up around $3/gallon, why wouldn't you do everything you could to get as much mileage as possible?

Answer 9

I would not wait too long, as the egr valve affects engine performance. if it is a torn diaphragm, you can have a vacuum leak that will cause the engine to run a little rougher, and rob your mileage. Stuck open, it can cause rough idle, so take it in...

Answer 10

Like said before, you won't an emissions test but luckily they are pretty easy to replace. My car failed an emissions test and the EGR valve was to blame. I took it apart cleaned it real good, reinstalled it and passed with flying colors!

Good luck!