The egr valve is there only to reduce pollution by recirculating exhaust gas back into engine at low engine speeds so blanking valve will increase emission. As current diesel mot test cannot check actual emissions only smoke you can get away with blanked egr valve.
For cleaning egr valve plenty swear by Forte air intake cleaner.
Quote: Originally posted by Tentz on 17/2/2013
The egr valve is there only to reduce pollution by recirculating exhaust gas back into engine at low engine speeds so blanking valve will increase emission. As current diesel mot test cannot check actual emissions only smoke you can get away with blanked egr valve.
For cleaning egr valve plenty swear by Forte air intake cleaner.
Spray on oven cleaner left over night, works a treat, spray it in and leave it, then give it an Italian job for 10 mins
Now comes the question: if blanking off on a non common rail diesel improves performance and consumption, why the heck are these engines fitted with them, there must be a reason ?? Also not recycling a percentage of the exhaust gases, could this effect the emissions??....Mick
It's fitted to reduce the emmisions making the car greener and cheaper to Tax.
The reason behind the egr valve is to reduce Nox emissions from the exhaust ,it does this by recirculating some of the exhaust gas back into the firing cycle to reduce the engine burn temperature.
Removing it will make the engine run hotter and this will reduce soot from the exhaust, its up to you whether or not you want to risk it as the engine will already have a elevated temperature any way while towing to me its not worth risking possible head damage.
Quote: Originally posted by twintens on 17/2/2013
mick how much did it cost for the decoke
Hi, it turned out to be a bit of a pain as in a bad spot up against bulkhead, so the only option was to remove exhaust manifold and valve as one lump then seperate on the bench. I know he soaked it something and was messing about with it all day on and off. Come the evening when he delivered it back to me he said "Don't know what to charge you give what you think" so I bunged him £100 but out of that he must have paid for the new manifold gasket....Mick
The engine doesn't always run any hotter it depends on the setup, 95% dont, I can prove this on the merc and mitsi's we work on for the MOD as each one has to run on the test bed, none run hotter. The majority of EGR valves are supplied from the exhaust manifold which runs through a cooler before entering the valve and into the engine, therefore blanking or removal eliminates this hot air from entering, Its also a well known problem that faulty EGR valves cause the 2.5 mitsi engine to overheat on the rear cylinders, thats why the later ones had the coolers fitted. We have a constant stream of merc engines with blown head gaskets that were sent out before the EGR removal program, no engines have suffered head failure due to EGR problems since the program started and they've gone back out into active service and believe me these vehicles get a lot more work than any average towing vehicle in much more extreme conditions.
------------- Doing as little as possible for as much as possible...