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Discussion Starter #1 (Edited)
I had all the classic problems of a failed EGR including power loss and the MSCF message.
I cleaned the EGR which didn't make much difference and had my specialist clean out the carbon from the rest of the inlet system, still no effect. Then I found some information on the Vauxhall equivalent of this forum explaining that the problem could be a seized solenoid - rather than the valve sticking.
Followed the instructions, took two hours but time could be halved I think, found the problem described, eased the stuck part and lo and behold problem cured. I had to drive a few miles and stop and restart a few times before the message went away but it did go. If you can do it yourself it may save you a couple of hundred quid.

I've used some pictures from the Vauxhall site and added some description here in the attached pdf files. I would have made it a nice convenient single file but forum rules limit the size of pdf attachements sorry. The rules also limit the number of files attached so the last page is missing but all it says is put it together the way it came apart so no great loss. When I get time I'll try to make it all smaller

Feel free to aks if you have any questions.

I hope some others get the benefit I did.

I've had a couple of further thoughts about this
Does the position that the solenoid seizes make a difference?
Stuck fully shut might make driving seem normal but would make the MSCF message appear

Could a little residual motion alter the symptoms?
Stuck slightly open might cause power loss but not display the MSCF message

I suspect the job will need repeating every year but I won't know for a year
 

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Discussion Starter #4
I did think about blocking it off but reading around suggests that the EGR does have a function in the engine - cooling the fuel charge for one thing.

The problem I had meant that the valve was jammed shut and was effectively the same as being blocked off as far as I can tell, the result was a continuous MSCF message.

I think I'd want to be a lot more knowledgeable about the inside of the engine before blocking the valve long-term but I'd appreciate an insight
 

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Jess - it stays fully closed when the throttle is fully open so I don't think it is majorly important for cooling the intake charge etc. If it was necessary, then diesels being used on trackdays would have major problems..
 

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Jess - it stays fully closed when the throttle is fully open so I don't think it is majorly important for cooling the intake charge etc. If it was necessary, then diesels being used on trackdays would have major problems..

you people believe in fairy tales. It's almost never closed, just connect diagnostic software and you'll see. EGR on diesel is like having some horses in trunk instead of engine. It just does ABSOLUTELY nothing good.
EGR is just to make stupid green people feel more happy about their political power. That's it. :)
 

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I normally just map the EGR function out of the ECU. Fit a blanking plate to be absolutely sure nothing is leaking through. Job done.
 

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I did think about blocking it off but reading around suggests that the EGR does have a function in the engine - cooling the fuel charge for one thing.

The problem I had meant that the valve was jammed shut and was effectively the same as being blocked off as far as I can tell, the result was a continuous MSCF message.

I think I'd want to be a lot more knowledgeable about the inside of the engine before blocking the valve long-term but I'd appreciate an insight

If the solenoid is sticking, its normally because its corroded, so the EGR will fail again. Minimum you should do is to replace the whole EGR. As others have stated, ideally you should blank it. The only purpose of the EGR is to reduce the burn temperature in the cylinder (and therefore reduce nox).
On the other hand the EGR:
introduces soot into the manifold, (which mixes with oil fed in through the breather pipe) gunking up the manifold, throttle body, inlets etc, this will reduce air flow through the engine over time (and power, worse efficiency), and increase the likelyhood of something else failing.
It reduces the O2 content of the air in the cylinders, reducing the burn of the fuel (as it is supposed to), in the real world it means the burn is less efficient, so less power and decreased fuel efficiency
It also increases soot production of the engine (the soot the EGR allows in acts as a floculant)
It takes the exhaust gases from just in front of the turbo, reducing the boost from the turbo, and decreasing performance (ever have to use the clutch a little more than you would like to?)
Its another thing to go wrong...again!

Give your MAP sensor a clean (it's just next to the EGR valve), this will show you exactly what the EGR is doing to your engine! Cleaning it will also help your engine run smoother.
 

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Been reading a lot on here about blanking so looked into plates.
Which is the best option solid or the ones with hole and why?
Do you (as some have suggested ) add the plates and leave the egr in plac e and connected so as to trick the ecu or do you need to get the ecu reprogammed. I am a diesel virgin and getting a little confussed :scratchchin:
While on the subject of blanking do I repair the swirl flaps with a metal kit or do I blank those off too. Again does this also require leaving the solenoid connected and/or need electronic wizard to remap???
I thought V6's were fun
 

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Been reading a lot on here about blanking so looked into plates.
Which is the best option solid or the ones with hole and why?
Do you (as some have suggested ) add the plates and leave the egr in plac e and connected so as to trick the ecu or do you need to get the ecu reprogammed. I am a diesel virgin and getting a little confussed :scratchchin:
While on the subject of blanking do I repair the swirl flaps with a metal kit or do I blank those off too. Again does this also require leaving the solenoid connected and/or need electronic wizard to remap???
I thought V6's were fun
Aye lad!

If you remove the EGR then chances are (older systems are okay) that your car's brains will realize that there's nothing on the end of the connector block to the EGR and get confused that the EGR is dead.. so you'll get an error on your dash. You need to program it out, so the brains don't know the EGR has gone AWOL.

So, Plan A is to remove the EGR, give it a good clean (since you're in there already) and then replace it with a blank at each end, in and out so that the EGR is still working but sealed/isolated from the rest of the system.

For logic/neatness the blank should be placed as far away from the EGR as possible... My old Stilo JTD (for instance) has a pipe from the exhaust manifold to the EGR and would be best blanked-off at the manifold.. to save the gas/crap going up the pipe into a dead end and accumulating in there (although that in itself isn't a problem). In reality the most accessible places for the blank plates are probably next to the EGR.

Make sure you blank the Inlet manifold side too... That saves oily mist from the oil breather (which vents into the manifold) getting dragged into the EGR and bunging it up, now that there is no gas pushing it the correct way).

The holey plates are for people who want/need to not blank off the EGR.. i.e. to keep it in the circuit. The holes help to swirl the gas .. mixing it better and helping to prevent some of the flat spots and other anti-social engine problems you might get.

But a plate with holes in is not a blanking piece (in the context of "blanking off the EGR"). It would still be exposed to exhaust gas and soot.. so (in theory) could still become blocked/jammed later, same as an un-blanked EGR would.

Ralf S.
 
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