ZX 1.9 D - EGR valve - blanking off

joss · Unread post by **joss** » 06 Aug 2008, 16:47

After increasing amounts of black smoke, and loss of power I have decided that my EGR valve is the culprit and has got to go. Is it ok to just disconnect or should it be blanked off?
My other car is a Vauxhall and I know they sell official blanking plates for their EGR valves.
Does anyone know of a source (or how to make one up)?

Or will pulling off the pipes do the job?

Also any tips for getting rid of all the soot which is choking my engine?

jeremy · Unread post by **jeremy** » 06 Aug 2008, 20:30

Try a search of this site - there's loads of info on EGR valves on Xantias on here.

Must be a late ZX 1.9D - our 94 hasn't got one.

MikeT · Unread post by **MikeT** » 06 Aug 2008, 22:42

I would highly recommend blocking off the EGR ports at the exhaust or inlet manifold but you won't find the gunk miraculously disappears, just stop it getting worse. See my Blog for a pic of what it's done to mine

However, what makes you think the EGR is responsible for the symptoms you give? The reason I ask is I don't think the deposits can build up rapidly enough to be noticeable.

citronut · Unread post by **citronut** » 07 Aug 2008, 07:58

you will clear a lot of the soot by giving the car a MEXICAN tune up, find a nice clear stretch of road preferably with out to many other cars around, especialy behind you, stick it in second gear and floor it for a few seconds, do this two or three times,

all the above if there is not another problem which is causeing your symptoms,

like maybe to much chip fat????????

regards malcolm

joss · Unread post by **joss** » 07 Aug 2008, 10:25

Jeremy - yes its a 97.

Disconnecting the vacuum pipe has had an instant effect - lots more power, no smoke. Actually revs above 3k now, it simply couldn't do it before.

The car has already had the cat block up completely with soot. It improved for a while after I got rid of that but the symptoms were returning - I think the EGR had been causing problems for a long time before I was given the car a few months ago.

And currently running on bio when available, DERV now and then, no chip fat atm.

Other half is taking it for a blast over the mountain road today...

Mike, how are you intending to blank yours off?

Unread post by **CitroJim** » 07 Aug 2008, 10:40

joss wrote:Mike, how are you intending to blank yours off?

Given the design of the valve, unless it is leaking, I don't really think you need to really worry too much about blanking it off. Removing the vacuum pipe is sufficient to disable it fully. Do block off the vacuum pipe though to prevent possible problems with other vacuum operated devices on the car.

I think your quick test has shown that it is at least not leaking

MikeT · Unread post by **MikeT** » 07 Aug 2008, 10:42

joss wrote:Disconnecting the vacuum pipe has had an instant effect - lots more power, no smoke. Actually revs above 3k now, it simply couldn't do it before.

I learn something new everyday

I wonder if there's a difference between the way it affects the N/A induction over the turbo version.

joss wrote:Mike, how are you intending to blank yours off?

I would prefer to get the manifolds welded but a blanking plate (in place of the gasket) where the EGR mounts onto the exhaust manifold should do it.

joss · Unread post by **joss** » 07 Aug 2008, 11:27

It really does feel like the engine can breathe at last.

Well if you are getting a plate made up Mike, please give me a shout!

I have just taped up the vacuum pipe for now - how should I block it off?

MikeT · Unread post by **MikeT** » 07 Aug 2008, 13:03

I'll see if I can find the post about the blanking plate - think it was steelcityuk that had done it.

On my MK1 xantia I just used a rubber cap that fitted snugly over the valve spigot. I didn't have to cap the vacuum pipe because my solenoids had failed and would never open again but maybe something like a pen top will wedge in there?

MikeT · Unread post by **MikeT** » 07 Aug 2008, 13:13

See thread 23831 page 3 about seven posts down.

He stated "I used a old Waxoyl tin to make the blanks from" which I suspect is soft enough metal to easily cut and resists the temperatures.

Here's the pic he posted of one port blanked..

jgra1 · Unread post by **jgra1** » 07 Aug 2008, 13:25

I have a thin sheet of steel and a hole cutter... if i get the chance i will see if I can make one or more of these in next few days

keep you posted...

Mike, how do I search for post 23831 ? am being sily here I think

MikeT · Unread post by **MikeT** » 07 Aug 2008, 13:27

If you design an easy DIY kit you'll probably make a small fortune on ebay.

joss · Unread post by **joss** » 07 Aug 2008, 13:29

Excellent, thanks jgra1. I don't have any skills or tools for fabrication!

Tape isn't doing the job - cold start was harder, and that's run off the same vacuum I think? (No idea how it works though)

jgra1 · Unread post by **jgra1** » 07 Aug 2008, 13:30

Joss no worries

I am a bit limited in those departments too

I basically work out of a tin roof shack in the corner of a field

MikeT · Unread post by **MikeT** » 07 Aug 2008, 13:34

All the cold start device does is lower the fast idle (which is default) once the engine warms up.