Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20741
London Lad wrote:
Just a thought.....
If you had a working valve and you cut the prongs of the actuator and put it all back together with the valve closed (or blanked) then the actuator would work the feedback resister and the system would think the the valve was opening and closing when it wasn't really. ????
That could possibly work on an 07MY>on EGR valve, but then its even harder to get at the valve.
One of those valves were totally minced, and the other was intermittently faulting
Think they had covered approx 40k too
22nd Jan 2009 8:11 pm
disco3cb
Member Since: 07 Dec 2008
Location: Alberton
Posts: 75
Thanks for the time and effort put in here, very interesting. Would like to see what condition the working one is in.
I think this is enough evidence to change your mind about becoming EGR-less.Disco4 SDV6 HSE 2013, Faultmate MVS2.
22nd Jan 2009 9:09 pm
stapldm
Member Since: 11 Sep 2006
Location: Swine Town
Posts: 2330
ridgeback_moor wrote:
...because if you apply 12v to the actuator it opens all the way. I suppose the ECM may pulse it to open or shut in small increments.
Often servos are driven with a PWM signal with the duty cycle used to cause the movement, with 50% being stationary. The peaks and troughs of the PWM are actually +3v/-3v or +12v/-12v etc, so at 50% it oscillates between turning one way and the other and due to the frequency used the actuator doesn't actually move, although you may hear it humming/buzzing.
You should find that if you apply the 12V the other way around, the actuator will slam to the opposite endstop. If not, then it's something unusual Dr. Ian Malcolm:
"Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should."
Transgenic tomato anyone?
22nd Jan 2009 9:55 pm
10forcash
Member Since: 09 Jun 2005
Location: Ubique
Posts: 16534
And because it's a closed-loop feedback system, the PWM signal varies dependent upon the value (or position) from the variable resistor
You should find that if you apply the 12V the other way around, the actuator will slam to the opposite endstop. If not, then it's something unusual
That's exactly what happens Previously:
2005 D3 2.7 TDV6 S
1984 90 2.25 Petrol CSW
1992 90 200TDi Hard Top
1995 Discovery ES 300TDi
2003 90 TD5 Truck Cab
22nd Jan 2009 10:23 pm
ljason286
Member Since: 11 Dec 2007
Location: Barham
Posts: 174
how do i know when i have got the same fault with my car with out taking them off the car and checking them
what happens when one goes wrong
hows the car or do you get a light come up
22nd Jan 2009 10:25 pm
10forcash
Member Since: 09 Jun 2005
Location: Ubique
Posts: 16534
most of the time the MIL on the instrument pack will illuminate - but not always... if it's stuck open (bearing failure) then a dramatic loss of power is evident, stuck closed, no driveability issues but the ECM may fall back to a lower power mapping
22nd Jan 2009 10:30 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20741
Click image to enlarge
Seen this a few times also :whistle:
Admin note: this post has had its images recovered from a money grabbing photo hosting site and reinstated
23rd Jan 2009 11:26 pm
RR38HANS
Member Since: 22 Jul 2008
Location: BRUGES
Posts: 179
From the pictures, I see that the blanking plates are on the "cold" side of the servo.
Would it not be better to blank the "hot" side, so that no further carbon depossits can block the valves in the future.
During normal operation there is a gass flow, so deposits are partly drawn into the engine, but if cold side is blocked deposits can build up, in the cavity that is created, around the valve even doing more damage in the long run.
Blanking plate on the hot side = valves on the clean cold side = no more deposits = longer lasting egr valve05 TDV6 HSE AUTO 7seats, tonga green/alpaca, alpine roof, privacy glass, tow kit, wood kit, 20" stormers n summer, 18" in winter, fancy exhausts, rear seat ent., club fooked turbo!
RANGE ROVER 1995 SOFTDASH (sold)
RANGE ROVER 1997 P38 (sold)
TRIUMPH TR6 OD
LOTUS EXCEL SE
AUDI A2 TDI
Carbon deposits don't seem to be the problem. Corrosion of the actuator/motor, valve heads shearing off, and position sensor faults seem more likely to cause problems. Any build up of carbon around the valve seat and stem, caused by the valve being open but the gas flow blocked by the blank, would be so small that it would be cleared when the valve closed anyway. With no exhaust gas flowing into the EGR cooler and valve, there would be virtually no carbon particles carried into that area anyway, IMHO. Also, access to the input side of the EGR valve (to fit a blank) is very difficult compared to the output side.Previously:
2005 D3 2.7 TDV6 S
1984 90 2.25 Petrol CSW
1992 90 200TDi Hard Top
1995 Discovery ES 300TDi
2003 90 TD5 Truck Cab
27th Jan 2009 4:33 pm
S t e F
Member Since: 18 Jan 2007
Location: Brasschaat
Posts: 15
Well, last monday the dealer changed both under warranty on our D3 07 (April).
He told me they had to change them a lot on 07 and 08 models.HSE Diesel, Automatic, Tonga Green, Alpaca Leather, 7 seats, SatNav.
5th Feb 2009 2:32 pm
Ollram
Member Since: 04 Dec 2006
Location: Gortynia
Posts: 605
definetely an issue for our D3
5th Mar 2009 5:15 pm
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20741
Just incase anyone hasnt seen it yet, and is interested in replacing them, heres a guide. Not complete for all MY's and both sides, but watch this space. Will update thread as they get done
Member Since: 19 Jul 2005
Location: Walkabout
Posts: 628
blanking EGR valves
Having read all the posts still unsure, is blanking the EGR exhaust a permanent fix?
I have a 04 D3 50Kmiles suffering intermittent power loss. Power comes in above 2000RPM when not running properly inline with the turbo. But next key turn car can run normal with accellaration throughout the range.
Is fuel filter a possible cause? Or is this just wishful thinking?
If the fuel filter is blocked you'll most likely get an engine fault message, and go into reduced power mode - at least that's what happened on mine, and it registered a low injector pressure fault code. The intermittent power loss you mention does sound like an EGR problem - can you get it checked for fault codes? For the sake of a 2p piece or blanking plate, it's worth trying IMHO.Previously:
2005 D3 2.7 TDV6 S
1984 90 2.25 Petrol CSW
1992 90 200TDi Hard Top
1995 Discovery ES 300TDi
2003 90 TD5 Truck Cab
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
