Some thoughts on the 2.2 C5 EGR SYSTEM (Long)

KevMayer · Post by **KevMayer** » 03 Mar 2011, 23:45

tonto,

To get the best benefit from EGR3 you need to squirt it in as close as possible to the inlet of the inlet manifold.

If you squirt it in at the MAF connection then it's got to got through the turbo, intercooler and all the air ducting. This must effect the way the spray is distributed.

I took the pipe off the top of my intercooler (the pipe between intercooler and inlet manifold) and squirted up towards the inlet manifold.

cachaciero · Post by **cachaciero** » 03 Mar 2011, 23:50

tonto wrote:Hi cachaciero

I hope...Thanks..PS. is it possible the s/valve diaphram is holed.
Dave

Very much so there were no less than five holes in mine when I changed it

All these holes were on what is for want of a better description a fold line in the rubber the effect being that the leak was not consistent in that the amount of leakage depended on the position of the diaphragm and could even be different one day to the next.

At idle you will probably not notice any change in revs by closing the valve if it is open, it will be noticable driving it due to a higher velocity more turbulent air flow into the cylinder resulting in better fuel air mixing and improved combustion.
The one problem with the leaking vacuum theory is that usually if there is a leak around the swirl valve it usually means that there is not enough vacuum to control the turbo. This lack of control causes the Turbo to overboost with resulting Anti Pollution messages and the ECU switching into LIMP mode i.e engine limited to about 2.3K revs. Now you are not getting Anti Pollution or LIMP mode which means that either the turbo is under control or you have another problem.
Would suggest another check is to look for air leaks between the turbo and manifold, if you put your hand around the rubber pipe that runs from the inter-cooler into the manifold and get somebody to rev the engine you should be able to feel the pipe swell a little as the turbo pressurises the system, worth also checking the inter-cooler for leaks another common problem.
Would suggest that next time you inject EGR3 you do it straight into the manifold you will have to take the pipe of from the turbo and once it's of you can check that you have a good flow of air out of the pipe from the turbo.

I suspect that the Anti Pollution messages after using EGR 3 injected into the MAF is because it leaves a residue on the MAF which upsets it's calibration for a while.

cachaciero

mooseshaver · Post by **mooseshaver** » 04 Mar 2011, 08:46

cachaciero wrote: I suspect that the Anti Pollution messages after using EGR 3 injected into the MAF is because it leaves a residue on the MAF which upsets it's calibration for a while.

cachaciero

When I sprayed some stuff in mine (straigth in to turbo) I got an esp fault, which I assumed was becasue the car could sense something was different as I ahd a pipe off?

I've ordered some EGR3 stuff. It comes with some other gunk to stick in the fuel tank as well.

The stuff that goes in the fuel tank, like most addatives for diesel, is based on cerium. Isn't that what the Eolys is based upon? It claims to lower combustion temp, which is what Eolys does. So are Citroens with particulate filters cleaner than ones without (ignoring the EGR)?

cachaciero · Post by **cachaciero** » 04 Mar 2011, 09:27

mooseshaver wrote:
The stuff that goes in the fuel tank, like most addatives for diesel, is based on cerium. Isn't that what the Eolys is based upon? It claims to lower combustion temp, which is what Eolys does. So are Citroëns with particulate filters cleaner than ones without (ignoring the EGR)?

Yes I've seen the offer you have taken up

and yes cerium is the same stuff that goes into Eolys. Specifically Eolys when part of the combustion process modifies the carbon formed during the combustion process such the resulting carbon has a lower combustion temperature than it would otherwise have by about 100 degrees.
The FAP will collect all the soot (carbon) produced in the combustion process.
The carbon treated with cerium has a burning temperature low enough to be burnt in the FAP at the exhaust temperatures achieved under medium / high engine loads and if not then by the regen process.
So yes engines with a FAP are much cleaner in terms of particulate emissions than ones without.

The fuel / injector cleaner you quote will for the time it is in the tank also allow carbon that is produced to burn at lower temperatures, won't make any difference to a car without a FAP though as the carbon particles will still go through the exhaust into the environment. I can't see that it would do much for carbon previuosly formed by not treated fuel in the combustion space but I could be wrong.

cachaciero

mooseshaver · Post by **mooseshaver** » 04 Mar 2011, 10:01

Sorry to be confusing, I meant that the insides of the engine would be cleaner on FAP cars due to the cerium always being in the fuel, and perhaps we don't need to buy fuel system cleaners?

When my car had a new EGR, it was an amazing difference. Even when the car didn't do its hesitating thing it good.
So I've passed my old EGR onto a local garage who will see if it can be cleaned and then swap it back into car on Monday. Will hopefully notice a difference.

cachaciero · Post by **cachaciero** » 04 Mar 2011, 10:32

mooseshaver wrote:Sorry to be confusing, I meant that the insides of the engine would be cleaner on FAP cars due to the cerium always being in the fuel, and perhaps we don't need to buy fuel system cleaners?

Ah! yes see what you mean yes I was thinking about that as I wrote the last bit and yes I guess that within the combustion space it should be cleaner or maybe not....

For the temperatures to get hot enough to burn the carbon out of the FAP the catalyser is part of the equation this is responsible for raising exhaust gas temp to a level at which the carbon will burn. For much of the time combustion temps will not be high enough for even cerium treated carbon to burn and EGR only makes this situation worse.
So my best guess is that cerium would do very little to keep the combustion space clean, the way to get a cleaner engine from a carbon point of view is to get rid of the EGR.
Go back through this rather long thread and you will see that there is some speculative evidence that suggests that FAPs have had to be fitted just to reduce the increased emmisions of carbon particulates caused by the use of EGR to reduce NOX.

cachaciero

MikeT · Post by **MikeT** » 04 Mar 2011, 13:49

From what I've read the Eolys(sp?) leaves deposits itself and they can't be burned off.

cachaciero · Post by **cachaciero** » 04 Mar 2011, 18:33

MikeT wrote:From what I've read the Eolys(sp?) leaves deposits itself and they can't be burned off.

True when the carbon containing cerium is burnt off in the FAP the cerium remains as ash, together with any ash products from burnt lubricating oil, it is this ash which ultimately chokes the FAP in a correctly working system.

cachaciero

Post by **myglaren** » 04 Mar 2011, 18:40

One of the primary reasons for using a low-ash lubricating oil then.

The whole thing seems rather ludicrous.

The intentions are good but the reality seems to fall way short.

cachaciero · Post by **cachaciero** » 04 Mar 2011, 18:58

myglaren wrote:One of the primary reasons for using a low-ash lubricating oil then.

Indeed!

The whole thing seems rather ludicrous.

The intentions are good but the reality seems to fall way short.

As a friend of mine once said "if you want a good argument find another subject "

Mind they seem to have done better with the later 2.2 albeit at the expense of a complete change to the top end plus a second turbo

plus changes to the FAP and Eolys
and more sensors in the exhaust which really shows just how wrong they got it on the first 2.2.

cachaciero

cachaciero · Post by **cachaciero** » 08 Mar 2011, 14:00

While do some digging around on something else I found the following which is primarily Renault related but adds another dimension / consideration to disabling an EGR system.

On 1.5 and 1.9DCIs EGR valve should open to allow carbon dioxide, which acts as a cooling gas) into the combustion chambers when the engine is under load (>30% boost). This allows the combustion chamber temperature to drop and thus the temperature of the exhaust gases. If it sticks in the closed position the exhaust gas temperature will rise causing a) the turbo bearings to fail and b) engine oil into the induction system. This will cause the engine to go on running until it has consumed all its oil and then it will go bang. Problems with EGR valves in Renault dCi engines are often the cause of rough running when the valve is stuck in the open position as well. In several cases turbos have blown but the EGR valve has not been replaced. Inevitably the new turbo unit will not last long.

Now 1.6 Hdi's have a reputation for short turbo life which I believed was down to poor oil supply due to the inline filter blocking but I wonder........?

cachaciero

KevMayer · Post by **KevMayer** » 09 Mar 2011, 18:30

It's been a few days now since using the EGR3 spray to clean out my inlet manifold and inlet valves and also to clean the EGR valve.

I'm seeing about 2 mpg improvement in fuel consumption and the performance is greatly improved. Better acceleration and the engine feels smoother on tickover and generally purrs along.

Overtaking is rapid. In fact, I've used a tuning box for some time and not really seen any improvement in performance or economy. I removed it a few weeks ago, but, the performance now with the engine set up as standard is great. The EGR3 spray has made a genuine difference. My inlet valves must have been well clogged up.

corsehf · Post by **corsehf** » 23 Mar 2011, 11:04

Any further improvements with using this EGR3 Spray??
Much difference? - no difference??

dieselnutjob · Post by **dieselnutjob** » 23 Mar 2011, 18:00

On saturday I cut up the top of a sardine tin with a pair of scissors and slipped the piece in between the pipe that comes off the EGR and the inlet manifold.
No problems so far.
This is on a 2001 Peugeot 607 2.2 HDI automatic

With FAP (nearly blocked) 29mpg
without FAP about 33mpg
without FAP and without EGR about 36mpg so far

I removed the EGR on our 806 HDI at 120,000 miles. It has now done over 200,000 and the turbo hasn't suffered, even towing a caravan.

I only use fully synthetic oil on a HDI though, always have, always will

KevMayer · Post by **KevMayer** » 23 Mar 2011, 19:51

The EGR3 spray has transformed my 2.2 Hdi.

Better economy and far better power/performance.

I'm very impressed. I wish I'd known about the spray years ago.