EGR Valves

[Pillock]

Are they in the slightest bit useful?

 

Leon economy has been suffering a bit recently, down from 46-47mpg to 41 on the last fillup and this tankful seems to be going the same way. I was browsing forumz at work and found a suggestion that a faulty EGR valve can lead to all my symptoms - lack of power below 2000rpm (but goes like a rocket over that), lumpiness on part throttle, and poor economy.

So I unplugged the little pipe on top, which goes into the flat round thing and appears to be some sort of actuation vacuum thing. Plugged the pipe with a screw and left the EGR valve unsealed.

 

On the way home from work, it seems to have been perkier - immediate throttle response at any revs, and on that short journey it *seems* to have used less fuel (although hard to tell).

 

So am I safe to leave it in this condition? Will I need to reconnect for MoT?

It's been suggested that I take the valve off and run some cleaner through it, but I'm lazy and things always go wrong when I do stuff like that.

 

Here's the bit in question:

 

[Rocket88]

Depending on what year your Seat is, you can get a rather swish alloy EGR by pass valve that solver the problem...........

[Pillock]

Swish? Alloy? That doesn't sound the Autoshite way! A length of drainpipe and some gaffer tape....

 

Actually, whilst tucking into my sausage and mash this evening I realised there was a selection of useful looking bits I robbed from the old engine in the car. So I went out to the shed just now and sure enough, one intake manifold complete with EGR valve

Needs a bit of a clean so I'll go about getting some cleany stuff (will carb cleaner do it? I don't know what's in these things) and clean it with said cleany stuff. I can see why it guffs up though, it looks like there's quite a tight tolerance on it and hot gas + crankcase fumes = yuck

[dollywobbler]

Carb cleaner should do it. They're there purely for emissions though. Think the MOT has changed its view on their deletion but people seem to be bypassing them all over the shop - largely because they just gunk up and ruin your engine.

[Pillock]

So what's the best way to disable them? At the moment I've pulled the hose off the pancakey thing so that's just open to air, and rammed a screw into the hose. The valve is therefore not capped or anything.

Has this had the required effect, or have I had the opposite? Should I have left the hose connected to the EGR, pulled the other end off and blanked that? Or blanked both ends? I has some spare hose (I think).