Technical EGR valve problem

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Technical EGR valve problem

technologyhelp

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My engine smoke on acceleration.When diagnosed found out this is due to EGR valve.Can anyone guide where to buy the part for fiat croma 1.9 D 2006?
 
Hi Technologyhelp, welcome to the forum!

Ref EGRs, you'll find out everything you need to know about them by using the search tool. Eurocarparts (ECP) usually have them in stock and you'll find them on their website which is cheaper than just going into a shop. Other parts suppliers, e.g. On ebay are available. Just search for egr fiat croma and you'll be spoiled for choice.

However, before you do can someone else confirm that an egr problem would cause smoke? It's not something I remember ever seeing here.

The common issues caused by the egrs are power / stutter / check engine.
 
Yes,a saturated EGR can and will cause heavy black smoke during accelerating.
Cleaning will only help temporary, even fitting a new one won't help for long, as the whole inlet is covered with carbon and sooth.
Only option: close it, and have a chiptuner delete it from the ECU.
 
@technologyhelp
Which 1.9 JTD do you have, the 8 valve or 16V? It should say Multijet 150 on the boot if you have the 16V. The EGR valves are different. You say "when Diagnosed", did you deduce the EGR valve is at fault or did a garage tell you? Sometimes cleaning it is enough to get it working again. Put cleaning EGR in the search box. There is a modification to fit a restrictor plate see https://www.fiatforum.com/miscellan...v-mjtd-egr-valve-restrictor-installation.html This can help reduce problems. Technically deleting or fully blanking the EGR valve in the UK is illegal, an MOT fail (But they can't tell if you have done it) and invalidates your insurance.

Robert G8RPI.
 
I'm not sure that EGR issues will create loads of soot in cars/engines fitted with DPF filters. EGR is just a bypass so yes raw soot is sucked out before would otherwise normally be shot down the exhaust pipe to the DPF but this soot is just re-ingested and then sent back down the pipe to the DPF. If the DPF is doing its job then final soot emission should be low.

In cars without a DPF I'm still not sure why EGR would cause excessive exhaust plumes. EGR is taken from the exhaust manifold. The exhaust manifold has the full 100% of soot and *hit the engines produces so recycling a small percentage should not make that much difference.

My only question I've yet to reason/research is how does EGR really affect fuelling levels. All diesel engines under heavy dynamic load produce a lot of *rap especially at lower rpm speed where fuel is just pumped in.

Any excess fuelling in a diesel engine produces loads of soot. Unlike a petrol engine diesel engines need lots of fuel to get up and go and thus when dynamically loaded we see the exhaust effects.

If the poster has a Croma fitted with a DPF and is seeing loads of smoke/fumes/soot/*rap out of the rear view mirror then this could indicate that his DPF filter is deteriorating or has blown through. (dropped its guts).
 
The restrictor plate is crap, but indicates the design fault the factory made when putting the EGR on....!!
After being fed up with loads of black smoke when passing or accelerating, I closed the EGR on my Alfa Romeo GT jtd, happy ever since...!!
Just came back from a very fast trip to Italy, the engine oil is still not all black, like it used to be after a short time, and the rear of the car is still clean....!!
 
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I'm not sure that EGR issues will create loads of soot in cars/engines fitted with DPF filters. EGR is just a bypass so yes raw soot is sucked out before would otherwise normally be shot down the exhaust pipe to the DPF but this soot is just re-ingested and then sent back down the pipe to the DPF. If the DPF is doing its job then final soot emission should be low.

In cars without a DPF I'm still not sure why EGR would cause excessive exhaust plumes. EGR is taken from the exhaust manifold. The exhaust manifold has the full 100% of soot and *hit the engines produces so recycling a small percentage should not make that much difference.

My only question I've yet to reason/research is how does EGR really affect fuelling levels. All diesel engines under heavy dynamic load produce a lot of *rap especially at lower rpm speed where fuel is just pumped in.

Any excess fuelling in a diesel engine produces loads of soot. Unlike a petrol engine diesel engines need lots of fuel to get up and go and thus when dynamically loaded we see the exhaust effects.

If the poster has a Croma fitted with a DPF and is seeing loads of smoke/fumes/soot/*rap out of the rear view mirror then this could indicate that his DPF filter is deteriorating or has blown through. (dropped its guts).
yeahthat.gif

EGRs put exhaust into the inlet, not more material in the exhaust. Normal operation should not increase smoke in the exhaust. If it is faulty, the ECU may change the fuelling to compensate resulting in smoke on non-DPF vehicles. A DPF will trap most particulates. I miss being able to change down and floor the throttle when someone is tailgating me
devil.gif
 
I will add.

Forget EGR for a moment. Diesel engines are dirty and create crap. With no EGR 100% of the crap goes out the exhaust. With EGR typically 90% goes out of the exhaust and 10% gets recycled. However the 10% recycled will go out through the exhaust. So 100% of the crap a diesel engine generates goes out of the exhaust! A DPF will filter this crap but has to burn more fuel and create more crap to keep itself clean. So as nothing can come from nothing (energy can not be created or destroyed but only converted from one form to another, and never at 100% efficiency - a basic physical fact) everything that is done to clean up etc. will cost more energy/fuel. There will never ever be a gain without a loss as nothing is 100% efficient.

The only way diesel combustion has been cleaned up is by higher fuel pressure and associated atomisation, multi-jet injection, more sophisticated engine ECUs and finally a exhaust nappy. However all of this comes at an energy expense. The subtle fact is that whilst we may see a 10% reduction in "local" city crap there must be a equivalent 10% increase in crap or energy consumption at a remote location we care nothing about.

Typical "as long as it is not in my back yard I don't give a toss".

Do not get me wrong. I'm all for more efficient and cleaner transportation etc. but the books have to balance as whilst I may be 10% better off so some poor sucker will be 10% worse off. If this person is not to be 10% worse off the 10% has to come from else where. I leave the rest as an exercise to the student in energy conservation.
 
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Getting back to the OP's question my suggestion at this stage would be to take of the egr and give it a good clean out with carb cleaner or similar to see if that makes any difference.

It's probably also worth checking the number of (recorded according to the ECU) oil changes and the last time it was told the oil was changed. How long have you had the car?

DPF and EGR faults are often misdiagnosed by the ECU and garages which lack sufficient knowledge. If you can get a laptop, an interface cable and a copy of MultiEcuScan we should hopefully be able to start to help.
 
Hello Technologyhelp there is a good set of photos on the astra forum of how to strip the egr valve including the solenoid end which can rust inside and stop it working .http://www.astraownersclub.com/vb/showthread.php/584028-How-to-Clean-EGR-including-solenoid
If you are thrifty as I am it looks worthwhile. I have fitted a plate with four holes drilled in it the reduces the exhaust gas but does not upset the ecu it's been on the car for two years or more with no trouble, I think it helps getting on the move and reduces lag. If the egr valve is stuck open then it would cause smoke as combustion does need oxygen to burn cleanly i am not sure if the dpf would stop all that smoke if the valve is stuck open. You will get a warning if the dpf gets blocked and needs a regen
 
100% agree about the bullet hole or swirl mod egr gasket. Totally transformed my car and it runs better with it fitted than it ever did without one when it was new.

From memory it cost about £4 delivered off ebay - best £4 I've ever spent.
 
100% agree about the bullet hole or swirl mod egr gasket. Totally transformed my car and it runs better with it fitted than it ever did without one when it was new.

From memory it cost about £4 delivered off ebay - best £4 I've ever spent.


Can you specify more about your car's transformation?
What has improved, 0-60, before and after, MPG, before and after, emissions, before and after, oil delution, before and after, etc.etc.


I didn't noticed any difference after fitting that 4 hole gasket.
Even after closing the EGR completely, I don't notice any difference in drivability, only less smoke during accelerating, and a cleaner rear of the car...
And the knowledge that it's a benefit for the longevity of the engine, that gives me piece of mind.
I do like to think it runs better though...
 
The engine runs more smoothly, no sutter at 2k revs and because it has that bit more power I can use 6th gear more often (in my 120bhp 8v Mjet) than if it's not partially blanked.

After a day or two I forget about it until it's time to clean the egr again.

If you want to see what difference it makes just take it out, go for a drive and it should be pretty clear, at least unless the egr is brand new anyway.
 
A restrictor plate creating (more) power...that's great...!!

As the plate is restricting the amount of (oxygen depleted) exhaust gas going to the intake, a small increase in power is not unreasonable. I've noticed an improvement in drivability and imroved fuel consumption since fitting a (genuine Fiat) 4 hole EGR restrictor to my 1.9 16V Croma.

Robert G8RPI.
 
Hi the reason I fitted a restrictor plate was that i was teaching my son to drive and he was struggling with clutch pick up because our Croma to be honest did not have much go getting on the move and it's asthmatic take up caused me to try a plate to help. I am pretty sure it did help and he soon mastered it and passed his test not to long after. I am unsure as to how the egr is programed but if it is open at tick over then to much co and co2 plus muck will certainly case a gutless take up and stalling even now if I need to get some power I have rev the thing and get the turbo moving to avoid being a nuisance at junctions it is superb however when on the move and those 150 horses really show up!
 
A restrictor plate creating (more) power...that's great...!!

Don't take my word for it. Take yours out, go for a drive and post back about whether you're going to go to the bother of refitting it or not.

My understanding is rather than creating power itself it reduces the loss of power caused by an ageing egr. Same result as far as driving it is concerned. And as for your comment about 5bhp, once the egr starts to go and you don't have a plate fitted you'll lose at lot more than that. At one point mine could barely make it up a hill. EGR blanked off and it drove fine.
 
EGR blanked off with a piece of tin lid cut to shape with tin snips and no holes at all just to prove it was the egr.

And all thanks to the helpful guys on this forum who've saved my sanity, and my wallet, many times now.
 
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