EGR Valve

My Super is running a lot better thanks to two new front pipes, but it's still a little rough at low revs. I know it needs a new Lambda, which I hope to have sorted soon. However, the engine management light is permanently on. The fault given is a faulty earth on the EGR Valve. Now all the earths have been cleaned and checked, but it's still giving the fault.

Looking around on the web, I found this as part of an explanation of what the EGR Valve does:

Now, since exhaust gas doesn’t burn, it doesn’t exactly help with combustion. At higher RPM’s, this really isn’t noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber

As it's the idle and low revs I'm having a problem with, could there be something else wrong with the EGR Valve that's causing the problem, or is it a red herring?

Whether this is the problem with the idling or not, I'd like to get rid of the engine management light on the dashboard, so does anyone have any ideas as to what the problem might be?

Originally Posted by badgers_nadgers

My Super is running a lot better thanks to two new front pipes..

Where did you get the pipes from -looks like I might be going the same way. Do you mind saying how much they were?

Cant help with the egr, I'm afraid. Didn't know they had one - mine doesn't but it's three years older than yours.

Originally Posted by mudhut

Where did you get the pipes from -looks like I might be going the same way. Do you mind saying how much they were?

Got them from Buypartsby for £290 inc VAT. This was very much cheaper than the dealer, which all the exhaust places I went to said I had to get it from. EB Spares do them as well for a similar price. I had to get the gaskets from EB Spares as Buypartsby didn't stock them.

The EGR valve works via a vacuum line controlled by a solenoid,poor idling can be caused by a bad seating within the valve assembly which will allow exhaust gas to leak through into the inlet manifold at inappropriate times ie- at idle,when it should be fully closed

There are various views on how effective/necessary this system is and replacement parts are expensive........after doing a bit of research I have completely removed my EGR system and fitted a blanking plate to the inlet manifold,the erratic idle that plaqued me for months is now rock steady.

I've also had a quick emissions test done recently with no problems,so I'm not swayed by the supposed environmental benefits of the EGR system either............and why did Alfa stop fitting it halfway through the production of 155's etc?