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Suspected EGR failure
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Chris Burmajster   
Sat Dec 06 2014, 01:34pm
Joined: Apr 03 2010
Member No: #81
Location: South East
 Recently, the engine management light came on and a message saying that engine repair needed (but no effect on performance) and so I took my car to my usual Indie. He plugged Lexia in and it said EGR fault. He sprayed it but it didn't work and now I'm facing the replacement of both valves. It appears to be a horrible job in terms of access. Has anybody replaced these valves or had them replaced and how bad a job was it? My car is a 2007, 2.7HDi with 82K on the clock.

Thanks,

Chris
gmerry   
Sat Dec 06 2014, 02:07pm
Joined: Dec 11 2009
Member No: #21
Location: Scotland
 Chris, there are two other current threads related to this.

The EGR system can fail in quite a number of ways: get your Indie to post with some live values and P codes as well.

Main thing is not to just change out the valves and not address the underlying problem (otherwise you may be back there soon enough)

Regards
G
Trainman   
Sat Dec 06 2014, 06:53pm

Joined: Apr 12 2010
Member No: #86
Location: Penwortham
 Chris, have a look at page 17 - Click Here - this is from when I had mine done, and yes it was a pig to get at the back one. The front one I believe is easier.....
Chris Burmajster   
Sun Dec 07 2014, 03:08pm
Joined: Apr 03 2010
Member No: #81
Location: South East
 Thank you both for your replies. I have passed them onto my Indie and the car is booked in with him in 3 day's time, so I'll report back.
Chris Burmajster   
Wed Dec 17 2014, 10:55am
Joined: Apr 03 2010
Member No: #81
Location: South East
 Right, the job has been done. The bill came to just over 1,000GBP. Ray had to remove pretty much the entire front of the car. It was 10 hours labour, plus the two valves and the ubiquitous tax. It took him two days to do the job, a job he had not done before. Ray showed me the old valves: both were sooted inside and the front valve had a spindle inside that looked as if it was rusty.

When I got the car back my first reaction was that I had spent a thousand quid to extinguish a light! However, as I drove it, I noticed that the engine was both quieter, smoother, more willing and when I floored it, it responded better than before. The slight roughness at motorway speeds had disappeared. Also, occasionally it kangarooed every so often, especially when cold. This seems to have gone too.

I wanted to know why the valves had failed and so searched the internet. One site was interesting: - Click Here -. It appears that others with my problem had much more noticeable symptoms like:

Incorrect engine performance characteristics
Possibly increased fuel consumption
Poor/No idle
Poor operation after cold start
Increased fuel consumption
Incorrect engine performance

My car had no such problems, or at least I didn't notice them. It could be that the deterioration was so slow that you don't notice it. The site also lists possible causes of EGR failure:

Faults in the crankcase breather/oil separator/engine vent valve
Increased blow by as a result of wear on the piston and cylinders
Turbocharger faults ie: worn bearings or blocked oil return line
Not changing oil or oil filters
Oil levels too high
Worn valve shafts or guides and as a result increased transfer of oil into the induction air channel
Out dated ECU software (in many cases updating this can solve the problems of excessive coke deposits)

but Ray thinks that none of these apply in my case as my car is in too good condition. Given that I plan to keep this car I think that it was money well spent.
gmerry   
Wed Dec 17 2014, 11:41am
Joined: Dec 11 2009
Member No: #21
Location: Scotland
 Hi Chris, did Ray identify the failure mode:

Eg, it can jam partially open so that there is continuous EGR (even when cold or idling or full throttle - all conditions when there should be No EGR)

Or it can jam closed

Or, the actuator can fail

Or, the position feedback can fail

etc

As you can see, lots of ways to fail and usually Lexia can be used to pinpoint the mode of failure. The reason why I mention this is because the valve(s) may fail again soon if the underlying problem is not dealt with.

Note, a bit of soot inside is normal and would not cause the valve to fail unless it was physically blocked
speedfix   
Wed Dec 17 2014, 09:26pm
Joined: Sep 28 2012
Member No: #1043
Location: south west
 Chris Burmajster,
"Given that I plan to keep this car I think that it was money well spent."

Well done to you and your garage the money is well spent and give you many miles of motoring.

IMO as the engines turbos etc do over 100,000 miles the advantage of useing premium fuel with a low ash 2-stroke oil added to the fuel [1:200] will work wonders.
IMO never a good idea to run the car with the reccomended longer mile oil change.

Do a 10.000- 12.500 yearly change with filter.
IMO less than 50000 a year just do a oil change no filter every other year.
Chris Burmajster   
Thu Dec 18 2014, 10:38am
Joined: Apr 03 2010
Member No: #81
Location: South East
Hi Chris, did Ray identify the failure mode:

Eg, it can jam partially open so that there is continuous EGR (even when cold or idling or full throttle - all conditions when there should be No EGR)

Or it can jam closed

Or, the actuator can fail

Or, the position feedback can fail

etc


I've asked Ray to look into this, as he still has the valves.

IMO as the engines turbos etc do over 100,000 miles the advantage of useing premium fuel with a low ash 2-stroke oil added to the fuel [1:200] will work wonders.
IMO never a good idea to run the car with the reccomended longer mile oil change.

Do a 10.000- 12.500 yearly change with filter.


I too run my car on premium diesel and NEVER leave oil in for more than 10,000 miles.

Chris
gmerry   
Thu Dec 18 2014, 11:10am
Joined: Dec 11 2009
Member No: #21
Location: Scotland
 Hi Chris, if the valves have been removed it will not be possible to tell unless "Ray" has a spare ECU or emulator and the correct plug/harness.

With an old style vacuum operated valve it was a bit easier.

Regards
G
Chris Burmajster   
Fri Dec 19 2014, 08:59am
Joined: Apr 03 2010
Member No: #81
Location: South East
 Hi G,

Thanks for your comment. It looks as if I missed the boat on that one! Ray told me that both valves were stuck shut, sooted up and the pillar in the front one looked as if it was rusty. Never mind, we live and learn. Ray has done a great job looking after both our Citroens over the years and I have learned to trust his judgement.

Chris
rwb   
Mon Dec 22 2014, 10:16pm
Joined: Dec 22 2014
Member No: #1988
Location: Telford
 If stuck shut then the system detects a fault because the amount of air coming through the MAF is greater than expected (and it will partially close the air doser to throttle the fresh air to try to encourage more recycling). Certainly on the 2.2HDi this is only an intermittent fault and doesn't cause the EML to come on. (Therefore EGR blanking works.)

So why not just use a blanking plate to disable the EGR? You'll notice better throttle response.
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C6Dave   
Tue Dec 23 2014, 09:49am

Joined: Oct 01 2009
Member No: #1
Location: Northumberland
rwb wrote ...


So why not just use a blanking plate to disable the EGR? You'll notice better throttle response.

Because technically your in breach of the new regulations and face a £1,000 fine for knowingly using a car with a blanked EGR or DPF removed......
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