I've just blanked my EGR valve off...
Discussion
...and I want to pick the brains of the PH collective.
Yes, I know the topic is dicussed here all the time, but this one is a little different.
I have just road tested my 2003 Mondeo TDCI after removing the EGR valve, giving it a damn good clean, and re-fitting it with a blind gasket to prevent the exhaust gasses re-entering the valve. First impressions are good- the engine feels more flexible in terms of delivering torque from low revs and following through to higher revs without any nasty flat spots. The soot from the exhaust is no longer visible in the rear view mirror, and if the 'net is to be believed, the engine will run more economically.
The disadvantages? I'm not sure. Blanking the EGR valve is a popular and well-documented modification, but no-one has really followed up on any conversations with feedback 30k miles later to let everybody know whether it caused any problems down the line. To compound the problem, some people on the 'net are saying that this mod will cause reduced power, economy, and might increase exhaust gas temperatures.
So, is there anyone well-informed on PH who can give me a definitive answer on the disadvantages of this mod?
A trawl of recent EGR-related threads just revealed lots of ill-informed speculation about why the valve was there in the first place if it's so beneficial to de-activate it! (We all know it's for cleaning up exhaust gasses, right?)
Yes, I know the topic is dicussed here all the time, but this one is a little different.
I have just road tested my 2003 Mondeo TDCI after removing the EGR valve, giving it a damn good clean, and re-fitting it with a blind gasket to prevent the exhaust gasses re-entering the valve. First impressions are good- the engine feels more flexible in terms of delivering torque from low revs and following through to higher revs without any nasty flat spots. The soot from the exhaust is no longer visible in the rear view mirror, and if the 'net is to be believed, the engine will run more economically.
The disadvantages? I'm not sure. Blanking the EGR valve is a popular and well-documented modification, but no-one has really followed up on any conversations with feedback 30k miles later to let everybody know whether it caused any problems down the line. To compound the problem, some people on the 'net are saying that this mod will cause reduced power, economy, and might increase exhaust gas temperatures.
So, is there anyone well-informed on PH who can give me a definitive answer on the disadvantages of this mod?
A trawl of recent EGR-related threads just revealed lots of ill-informed speculation about why the valve was there in the first place if it's so beneficial to de-activate it! (We all know it's for cleaning up exhaust gasses, right?)
Thanks for the responses so far, you've pretty much confirmed that I don't have much to worry about!
I think I might see slightly lower MPG on my short runs to work but on a longer run I suspect it'll be better. The net effect will be slightly worse MPG but the improvement in drivability and long-term health will make it worthwhile. I did disconnect the battery so that the ECU could 're-learn' it's parameters so it might get better over the next 100 miles or so.
Before I did it, there was an awkward flat spot between 1500 and 1800RPM, where the valve opens and sneezes a load of particulates into the inlet manifold. I was constantly having to drive round this flat spot before which is very irritating because at a cruise you're using this part of the rev range. If you do try to use an appreciable amount of throttle opening in this rev range, you'd get a massive cloud of smoke from the exhaust.
The car is much better now, feels like the engine it always should've been, It was free to do and the smoke is gone... #WINNING
I think I might see slightly lower MPG on my short runs to work but on a longer run I suspect it'll be better. The net effect will be slightly worse MPG but the improvement in drivability and long-term health will make it worthwhile. I did disconnect the battery so that the ECU could 're-learn' it's parameters so it might get better over the next 100 miles or so.
Before I did it, there was an awkward flat spot between 1500 and 1800RPM, where the valve opens and sneezes a load of particulates into the inlet manifold. I was constantly having to drive round this flat spot before which is very irritating because at a cruise you're using this part of the rev range. If you do try to use an appreciable amount of throttle opening in this rev range, you'd get a massive cloud of smoke from the exhaust.
The car is much better now, feels like the engine it always should've been, It was free to do and the smoke is gone... #WINNING
slaveunit- as much as I'd be happy to help, I'm afraid I confine my amateurish spanner 'skills' to my own cars... I just can't work on other people's cars with the same confidence.
I will say that if you can change a wheel you can fit the EGR valve blank, it really is that easy. Even if you want to remove and clean the EGR valve it's an easy job.
If it helps I can get some pictures, or do a bit of a write-up?
P.S. have you checked your car isn't going to throw up an Engine Management warning light? If you have the older style EGR valve like I do it won't, but if you have a later car with electrical connections on the EGR valve it will throw a warning light up.
I will say that if you can change a wheel you can fit the EGR valve blank, it really is that easy. Even if you want to remove and clean the EGR valve it's an easy job.
If it helps I can get some pictures, or do a bit of a write-up?
P.S. have you checked your car isn't going to throw up an Engine Management warning light? If you have the older style EGR valve like I do it won't, but if you have a later car with electrical connections on the EGR valve it will throw a warning light up.
Old thread! For the sake of closure I'll add that I got rid of the Mondeo in June last year and while most of the car was knackred, there were still no negative repercussions of EGR blankage.
I noticed a slight loss in fuel economy but I think that's down to all the short journeys I was doing- I think the exhaust gasses helped the engine warm up faster. On longer journeys efficiency was about the same.
I noticed a slight loss in fuel economy but I think that's down to all the short journeys I was doing- I think the exhaust gasses helped the engine warm up faster. On longer journeys efficiency was about the same.
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