EGR Valve
#21
04-29-2015, 11:42 AM
That is absolute b***+^%s! Why didn't he go into more depth and explain why it would cause so much grief. Might of fixed cars for years, replacing EGR valves and the like but obviously doesn't know technically how they operate. EGR valves do not usually work on idle or high to max revs. They are more of a long term nuisance than a massive benefit in my opinion.
On some cars you have to drill a tiny hole in the blanking plate as the Ecu is very sensitive and needs to see a certain amount of gas recirculating else a management light will pop up. For example my mates Volvo v50 needed a 1.5mm hole. Also on some engines there is an anti judder valve to stop too much judder when the engine is switched off, mainly for comfort and not much else.
If you get a chance I would strongly suggest that you look inside a new intake manifold then look at one after 10's thousands of miles with an EGR fitted. It is shocking.
One key element of decent fuel economy and power is a process called volumetric efficiency. If the intake manifold has been reduced in circumference due to oily soot build up then there is no way fuel econom/efficiency of the engine is going to be the best it can. A second key element is that a car with a turbo usually has an intercooler, it's purpose being to cool the charged air down to improve volumetric efficiency. If you are recirculating hot exhaust gases, again this will not help get the maximum mpg out of your engine, however it does remove harmful NOx going to atmosphere which is great for the guys in Brussels but they aren't going to fit the bill for your engine repairs.
If you do go down the route of blanking off the EGR valve I do think it best to remap the ECU to get the best improvement in mpg however you don't have too. It just helps remove it from the ECU so it has one less parameter to change and counter for.
On some cars you have to drill a tiny hole in the blanking plate as the Ecu is very sensitive and needs to see a certain amount of gas recirculating else a management light will pop up. For example my mates Volvo v50 needed a 1.5mm hole. Also on some engines there is an anti judder valve to stop too much judder when the engine is switched off, mainly for comfort and not much else.
If you get a chance I would strongly suggest that you look inside a new intake manifold then look at one after 10's thousands of miles with an EGR fitted. It is shocking.
One key element of decent fuel economy and power is a process called volumetric efficiency. If the intake manifold has been reduced in circumference due to oily soot build up then there is no way fuel econom/efficiency of the engine is going to be the best it can. A second key element is that a car with a turbo usually has an intercooler, it's purpose being to cool the charged air down to improve volumetric efficiency. If you are recirculating hot exhaust gases, again this will not help get the maximum mpg out of your engine, however it does remove harmful NOx going to atmosphere which is great for the guys in Brussels but they aren't going to fit the bill for your engine repairs.
If you do go down the route of blanking off the EGR valve I do think it best to remap the ECU to get the best improvement in mpg however you don't have too. It just helps remove it from the ECU so it has one less parameter to change and counter for.
#22
04-29-2015, 04:50 PM
The EGR [several different types] direct a portion [at certain times], not all exhaust gas at all times into the EGR unit, that's why blanking does no harm. As others have said sometimes on some year and model cars minor mods need to be made to allow some tiny amount of exhaust gas to be 'read by sensors as present' others do not. Here's a good example of 3.3 Chrysler [petrol] EGR, its location and replacement / refit.
#24
05-03-2015, 06:42 AM
update on the EGR valve guys , I have now blanked it off , it was not easy on mine because it is down the back of the engine , it sits on top on the manifold , you have to remove the pipe that goes from the front top the turbo , then the water pipe from the thermostat , and the heat shield from the manifold to make it easier to get to the front nut that holds the EGR valve down , the pipe that runs from the EGR to the inlet manifold was almost blocked with carbon , one question I have , the suction pipe from the EGR goes down to a little valve at the front of the engine , there is another pipe coming from that , that goes down to the brake master cylinder can I just unplug that valve now , I mean unplug the wire plug from it ,
picture below
picture below
#25
05-03-2015, 09:11 AM
A most interesting thread -- although I understand the point of the EGR system, all this practical stuff here is new to me and fascinating.
I'd welcome an explanation of Shaky's last question, partic. that electrically operated valve and what it does.
Leedsman.
I'd welcome an explanation of Shaky's last question, partic. that electrically operated valve and what it does.
Leedsman.
#27
05-03-2015, 01:20 PM
forgot mate there was no gasket on mine , between the EGR and the manifold , it was metal to metal
#28
05-03-2015, 01:51 PM
EGR valve I take it is Vacuum operated so is it open when no vacuum is there, engine stopped or is it closed. In other words when EGR is on the bench is it closed.
I'm just wondering if it can be permanently closed instead of blanking by putting direct vacuum link to valve or isolating the link.
Confusious says.
I'm just wondering if it can be permanently closed instead of blanking by putting direct vacuum link to valve or isolating the link.
Confusious says.
#29
05-03-2015, 02:14 PM
EGR valve I take it is Vacuum operated so is it open when no vacuum is there, engine stopped or is it closed. In other words when EGR is on the bench is it closed.
I'm just wondering if it can be permanently closed instead of blanking by putting direct vacuum link to valve or isolating the link.
Confusious says.
I'm just wondering if it can be permanently closed instead of blanking by putting direct vacuum link to valve or isolating the link.
Confusious says.