General egr valve

[Sleepy1]

Hi,

I read this string with great interest, my Multipla engine warning light was on and the FIAT dealer quoted almost £400 to fix. I got a diagnostic cable for £15 off eBay to check myself and the EGR was the culprit. A strip down (lots of grazed knuckles) and clean revealed the solenoid to be the fault so I've ordered a complete Vauxhall replacement ERG for £70 off eBay (I saw the bit about rebuilding the solenoid but the actuating pin is not sprung so I think it's US)

However, it occurred to me that if owners wanted to do a temporary test or permanently change the engine, without the expense of new gaskets/blanking plate and the spanner time (took me ages getting it off then on again), you could just undo the 4 torx screws retaining the solenoid and secure it safely out of the way but still connected. This way there will be no warning light but the valve remains firmly shut thus avoiding any problems, I'll probably give this a go myself to check MPG for comparison.
Also, if anyone's worried about exhaust gases escaping from the solenoid end, there are no gaskets and there are two gaps between the metal spacer and the body so the assembly definitely not is not airtight.

A better fix would be to get the engine management to ignore the solenoid and just disconnect it but that's way beyond me, so to silence that high pitched beeeep every time it's started, warning light from the dash and high pitched noise the wife makes telling me it's going to break down unless I fix it, I'm stuck buying a new one.

Cheers,

Keith

Just thought, if your valve is stuck open giving poor running, you would probably be able to pull/jiggle it shut from the exposed end when the solenoid is removed then leave the solenoid off - job done.

 

[Shadeyman]

Probabely the most common EGR fault is when the EGR sticks open due to a build up of crap and the car losses power, black smoke etc. In this case removing the solenoid would not help solve or diagnose the problem as the actual valve would still be stuck open.

 

[T14086]

Whilst an EGR reduces NOx gases, fuel consumption and Particulate Matter(soot) increases.

Yep and its the particulates that are real nasty, they absorb acid and are airborne and cannot be washed away. You cant see them yet they get in your respiratory system.

 

[Sleepy1]

Probabely the most common EGR fault is when the EGR sticks open due to a build up of crap and the car losses power, black smoke etc. In this case removing the solenoid would not help solve or diagnose the problem as the actual valve would still be stuck open.

Hi,

I must have been editing my original post when you were posting. Yes, stuck valves do seem to be the main problem but if you free it off by jiggling and bouncing it on the spring it should close properly and if you then leave the solenoid off, fixed in a fraction of the time and free.

 

[Shadeyman]

Install Bertye's Blanking Plate £4 delivered to your door

http://cgi.ebay.co.uk/EGR-blanking-blank-plate-VAUXHALL-FIAT-ALFA-SAAB-1-9-/120683909833

only 2 bolts to undo, not 4. No jiggling and bouncing plus the EGR is very securely held on with 4 bolts.

 

[Argonought]

I've had mine blanked off for a week pending fitting of new one and my MPG has gone up???

I'd say that clearly indicates it's either faulty or your MAF is inaccurate.

A good working EGR system should improve consumption rather than make it worse

If the EGR is completely blocked, purposely or due to a build up of crap, the only symptom("bonus" maybe a better word to use) is better MPG.

Whilst an EGR reduces NOx gases, fuel consumption and Particulate Matter(soot) increases.

Where's this come from

Compared to a defective EGR system then yes I agree (which based on your interesting article could include a suspect MAF sensor) but a fully functioning EGR should reduce consumption if anything.

The EGR effectively reduces the cc of the engine when it's not needed and replaces air with (largely) inert exhaust gas to do this. As a consequence less fuel is injected and fuel consumption should be reduced. This system will typically come into it's own on those light runs which require minimum throttle.

 

[Shadeyman]

A good working EGR system should improve consumption rather than make it worse

You have Petrol and Diesel EGR's mixed up. The reasons an EGR is used and the effects they have on Petrol and Diesel engines are very different. The Tech Talk PDF document attached to one of my previous posts will help explain the differences.

Where's this come from

Compared to a defective EGR system then yes I agree (which based on your interesting article could include a suspect MAF sensor) but a fully functioning EGR should reduce consumption if anything.

The EGR effectively reduces the cc of the engine when it's not needed and replaces air with (largely) inert exhaust gas to do this. As a consequence less fuel is injected and fuel consumption should be reduced. This system will typically come into it's own on those light runs which require minimum throttle.

Adding an EGR to a diesel reduces the specific heat ratio of the combustion gases in the power stroke. This reduces the amount of power that can be extracted by the piston. An EGR also reduces the amount of fuel burned in the power stroke. This is evident by the increase in particulate emissions that corresponds to an increase in EGR. Particulate matter (mainly carbon) that is not burned in the power stroke is wasted energy. Regulations on particulate matter(PM) call for further emission controls to be introduced to compensate for the PM emissions introduced by EGR. The most common is particulate filters in the exhaust system that result in reduced fuel efficiency.

 

[adamcot]

So what are the long term effects of raising the combustion temperature by removing the EGR? Running the cylinders too hot will cause detonation.

Why not solve the problem? As I suggested earlier in the thread, it would be interesting to see what causes the gunk to set inside the inlet manifold. I still think it is to do with the oil breather pipe, the gas from the exhaust shouldn't have any liquids to cause it to set. My advice, buy a cheap oil catch tank and see how it goes.

 

[lmrn1]

Has any one tried the vauxhall astra egr valve mention earlier in the thread, does it fit and any mods needed?

 

[Sleepy1]

I have one coming , if you search Seller assumes all responsibility for this listing.Item number: 220746080570 on eBay you can see it, can't post links being a newbie.

I'll post if it fits at the weekend.

 

[Sleepy1]

Install Bertye's Blanking Plate £4 delivered to your door

only 2 bolts to undo, not 4. No jiggling and bouncing plus the EGR is very securely held on with 4 bolts.

To do the job properly would also need 2 gaskets at £4.50 each. You can also use my method to assess if your engine runs better with or without the EGR at no expense, you'd need another gasket if you find the blanking plate makes the engine run worse or uses more fuel and want to take it off.
On the Multipla it's a real job to get at and undo the bolts underneath the EGR valve but the solenoid is very easy to remove.
Also the EGR is securely held to the engine with three bolts, not four.
Have you actually been hands on with an EGR valve?

 

[Shadeyman]

On the Multipla it's a real job to get at and undo the bolts underneath the EGR valve but the solenoid is very easy to remove.
Also the EGR is securely held to the engine with three bolts, not four.
Have you actually been hands on with an EGR valve?

My mistake, we were talking about the solenoid not the EGR, the post should have said

Install Bertye's Blanking Plate £4 delivered to your door

http://cgi.ebay.co.uk/EGR-blanking-blank-plate-VAUXHALL-FIAT-ALFA-SAAB-1-9-/120683909833

only 2 bolts to undo, not 4. No jiggling and bouncing plus the solenoid is very securely held on with 4 bolts.

 

[Argonought]

You have Petrol and Diesel EGR's mixed up. The reasons an EGR is used and the effects they have on Petrol and Diesel engines are very different. The Tech Talk PDF document attached to one of my previous posts will help explain the differences.



Adding an EGR to a diesel reduces the specific heat ratio of the combustion gases in the power stroke. This reduces the amount of power that can be extracted by the piston. An EGR also reduces the amount of fuel burned in the power stroke. This is evident by the increase in particulate emissions that corresponds to an increase in EGR. Particulate matter (mainly carbon) that is not burned in the power stroke is wasted energy. Regulations on particulate matter(PM) call for further emission controls to be introduced to compensate for the PM emissions introduced by EGR. The most common is particulate filters in the exhaust system that result in reduced fuel efficiency.

Shadey, I see you're still plagiarising in trying to respond to posts I make

http://fordwiki.co.uk/index.php/EGR_Valves_-_Explanation

Pity you didn't include the rest:
"....has a higher specific heat than air, and so it still serves to lower peak combustion temperatures; this aids the diesel engine's efficiency by reduced heat rejection and dissociation."

I can assure you EGR systems are not intended to increase fuel consumption on either a petrol or a diesel engine. Car engine designers strive for efficiency AND reduced emissions (which is pretty much the same thing anyway)

 

[lmrn1]

Hi sleep1

Yes have blanked it off runs much better. Can see the black stuff coming through. When I put the car on FES it says fault egr so think it will be faulty.

If you can let me know how you get on that would be brill

 

[Shadeyman]

Shadey, I see you're still plagiarising in trying to respond to posts I make

http://fordwiki.co.uk/index.php/EGR_Valves_-_Explanation

"plagiarising"
I read it in a mates car magazine, did you think I came up with all by myself? I asked him to scan the page and send it to me. I then typed it in. Its a very common paragraph that you can find on hundreds of websites just by pasting it into google. I suppose I could have given you 30 or so links to websites and the name of a few magazines.

Pity you didn't include the rest:
"....has a higher specific heat than air, and so it still serves to lower peak combustion temperatures; this aids the diesel engine's efficiency by reduced heat rejection and dissociation."

Aids heat rejection and dissociation, it does not improve performance(BHP) nor does it improve fuel efficiency(MPG) of a Diesel engine. From the website you linked to:

aids the diesel engine's efficiency by reduced heat rejection and dissociation. There are trade offs however. Adding EGR to a diesel reduces the specific heat ratio of the combustion gases in the power stroke. This reduces the amount of power that can be extracted by the piston. EGR also tends to reduce the amount of fuel burned in the power stroke. This is evident by the increase in particulate emissions that corresponds to an increase in EGR. Particulate matter (mainly carbon) that is not burned in the power stroke is wasted energy.

so stop quoting from the crapy Wiki sites.

I can assure you EGR systems are not intended to increase fuel consumption on either a petrol or a diesel engine. Car engine designers strive for efficiency AND reduced emissions (which is pretty much the same thing anyway)

Of course they don't intend for them to increase fuel consumption, they're intended to reduce NOx. Unfortunately the side effect of that process on a diesel engine is increased fuel consumption and less power.

 

[Argonought]

"plagiarising"
I read it in a mates car magazine, did you think I came up with all by myself? I asked him to scan the page and send it to me. I then typed it in. Its a very common paragraph that you can find on hundreds of websites just by pasting it into google. I suppose I could have given you 30 or so links to websites and the name of a few magazines.

Frankly the clap trap you come up with insults both your own intelligence and everyone who's stupid enough to read the rubbish you post.

It's obvious to everyone that you copy-pasted it.

Why make a pathetic excuse :shrug:

You found the article so why not try to comprehend it ?

Yes; the EGR system has advantages AND disadvantages and you're supposed to grasp both sets - and NOT concentrate on the negatives as if they're the only ones that exist

For instance you've completely failed to grasp that LESS fuel is injected during EGR (even if that fuel might not be consumed as efficiently)

 

[lmrn1]

Now children lets not argue. Everyone will have there own opinions. In my case it has made the car run better and has proved there is a fault with the egr. If you don't want to blank it off then don't.

If you look at some of the other threads on here one garage man will say a problem is one thing and another will same it something else. Different ways of doing things. You both have helped me find faults so lets all stay friends.

 

[Shadeyman]

There's only one person posting "Clap-Trap" in this thread and thats you.

Your wrong and you know it.
An EGR on a Diesel engine reduces power and increases fuel comsumption.

If you think posting Clap-Trap about where I sourced a particular paragraph will divert attention from the fact your wrong please continue posting more Clap-Trap.


"pathetic excuse"
The paragraph I typed in can be found on hundreds of sites.

Here's a PDF on one of those sites.
http://www.pitstop.co.nz/carservicing/modernexhaust.pdf

Here's a list of sites including this one.
http://www.google.co.uk/webhp?rls=i....&aq=&aqi=&aql=&oq=&pbx=1&fp=1d9bc39a3cb829be

I found it in a magazine.

 

[adamcot]

You shouldn't believe everything you read on every website you find We have no idea who wrote it.

There are benefits and also negatives to using the system. We can all agree on that can't we?

What you still haven't answered is what are the long term effects on running the car with higher cylinder temperatures?

 

[Shadeyman]

There are benefits and also negatives to using the system. We can all agree on that can't we?

What you still haven't answered is what are the long term effects on running the car with higher cylinder temperatures?

As a fully working EGR is shut off increasing the combustion temp when you put your foot down so I guess the answer is not much as my car has done over 100,000 miles now, the EGR must have been closed for most of those miles.

My EGR has been blocked off completely for quite a while now and my temp guage is still planted firmly in the middle, not hotter, not cooler, just the same as before.