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amondeggs
Member Since: 03 Sep 2009
Location: Telford
Posts: 155
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Hi Paul the revs rise and fall when accelerating hard or driving up a steep incline. If I drive without hard acceleration the car drives fine. I can provoke the car by accelerating hard. The worst vibrations are in 2 and 3rd gears as you say. If I am cruising along at 70 75 or so all is well but if I try to accelerate to overtake (hard acceleration) then the revs rise and fall a couple of hundred revs.
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4th Oct 2010 10:43 pm |
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Renton
Member Since: 13 Jan 2009
Location: Somewhere in the middle
Posts: 1718
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- My revs surge when accelerating fast and hitting the 2000revs.
- Or when I cruise in 6th gear, go back in speed and try to go faster again, still in 6th gear revs surge.
- Or cruising at a constant speed, driving up an long/steep incline, revs start to surge.
I can cure all of the above by shifting back 1 gear. CLUB ILLEGAL CAR WASHERS
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5th Oct 2010 7:54 am |
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amondeggs
Member Since: 03 Sep 2009
Location: Telford
Posts: 155
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Well have learned a little more about the D3 autobox. My car is in the workshop now "being investigated". Took it to local ZF specialist. Following a test drive they tell me it is the torque convertor that is at fault.
They will begin by testing the ATF for water content. They do this because the ATF is cooled by a portion of the cars radiator and they have had cars in the past where water gets into the ATF as the rad breaks up. If there is water contamination then it damages the whole transmission. So I am hoping that this is not the case !!! What they suggest doing is fitting a secondary rad solely for the atf ! so that the problem will not reoccur !
Hoping that the torque convertor is not badly damaged as they refub it and refit. They do use the "proper" expensive oil and they stress it has to be used! If the torque convertor is badly damaged they refit new genuine one. If the transmissioin is contaminated they will fit new torque convertor and refurb whole transmission.
I will keep you posted on the progress as they will not start work until next Monday.
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8th Oct 2010 5:53 pm |
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caverD3
Member Since: 02 Jul 2006
Location: Oberon, NSW
Posts: 6922
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I could be wrong but on the D3 the ATF is cooled through a pipe in front of the radiator so no chance of water contamination. I do not think they know the D3.
If it is the case and they tell you there is water contamination then they are havng you on. “There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely gamesâ€
Ernest Hemmingway
D4 3.0 Active Diff, Adaptive Lights, High Beam Assist, Surround Cameras, Privacy Glass.
D3 2.7:Adaptive Headlights,Electronic Rear Diff,ARB Bar,Blaupunkt Speakers,JVC Powered Subwoofer,Removable Snorkel,Mitch Hitch,Pioneer After Market Head Unit,Steering Wheel Control Adaptor,Remote Adjustable Supension Rod System, Taxside Dual Battery System.
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9th Oct 2010 1:33 am |
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PaulP
Member Since: 04 May 2007
Location: Barcelona
Posts: 4317
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I think it is the power steering fluid that is cooled separately in front of the radiator.
The auto transmission cooler is built into the radiator 2006 Discovery 3 TDV6 SE Auto Buckingham Blue
2007 Golf GT DSG
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9th Oct 2010 7:09 am |
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evo8
Member Since: 29 Jan 2008
Location: Zalesie
Posts: 289
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nissan pathfinder has had a recall for this issue in cca 2005- radiator leaking water into atf. However a flush and a modified radiator change has cured it and no damage to the automatic transmission has been done. Lets see if LR will have a similar problem. 2013 D4 TDV6 S; Baltic Blue; IID Tool BT
2007 D3 TDV6 SE, Auto; club Faultmate MSV2
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9th Oct 2010 7:47 am |
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caverD3
Member Since: 02 Jul 2006
Location: Oberon, NSW
Posts: 6922
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I think you are right. I stand corrected. “There are only three sports: bullfighting, motor racing, and mountaineering; all the rest are merely gamesâ€
Ernest Hemmingway
D4 3.0 Active Diff, Adaptive Lights, High Beam Assist, Surround Cameras, Privacy Glass.
D3 2.7:Adaptive Headlights,Electronic Rear Diff,ARB Bar,Blaupunkt Speakers,JVC Powered Subwoofer,Removable Snorkel,Mitch Hitch,Pioneer After Market Head Unit,Steering Wheel Control Adaptor,Remote Adjustable Supension Rod System, Taxside Dual Battery System.
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9th Oct 2010 8:19 am |
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stapldm
Member Since: 11 Sep 2006
Location: Swine Town
Posts: 2330
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Thankfully I'm not (yet?) in the same boat as you guys, but something about the comments in the thread has been bugging me; and I've finally figured out what it was. In the interests of getting to the heart of this issue (and not starting a fight ) I'm sharing my thoughts.
It's been commented that using command shift cures the problem, and also the issue has been blamed on the lock up clutch slipping. Ignoring the fact that there are no simple black and whites in a mechanical system such as this I see these reports of information as being contradictory.
If I have my own facts right, when in command shift the lock-up clutch is activated almost as soon as the gear shift occurs. This is what gives it a 'manual' feel. If the clutch was slipping excessively then you'd be able to slip the clutch in command shift and get your engine revs to vary/judder there too. As such I think some of the information we are receiving may be less than accurate.
In an early post there was a comment that the heat from the slipping clutch damaged the converter. As there are few moving parts in the converter are they referring to the one way clutch in the stator? As I thought these were pretty much bomb proof without friction linings being involved I'd be amazed to hear it was this.
EDIT : I've just Googled this, and stator clutch failure is common My bad.
In my head, there are still more outstanding questions than answers on this issue; I look forwards to learning more about it and for everyone to reach an acceptable end to their permagroan. 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?
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11th Oct 2010 9:40 am |
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Renton
Member Since: 13 Jan 2009
Location: Somewhere in the middle
Posts: 1718
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Thanks stapldm for thinking along.
Command shift doesn't cure it. When continuesly driving in command shift the problem is there as well. What I do is use the command shift to keep the revs high on accelerating or going up an incline.
I spoke to a ZF specialist a while back also and he claimes that it has nothing to do with the gearbox/torque converter. He was prety sure it was a turbo issue. Turbo doesn't provide enough power causing the enigine to judder. I did perform a turbo clean but didn't cure it. However the turbo cleaner doesn't clean al the turbo pipework. So I need to remove the turbo to get to all the piped/exhaust.
Many jaguars have the same box/converter and on these cars they replaced many converters which cured the problems.
Any news from you Amondeggs/PaulP? CLUB ILLEGAL CAR WASHERS
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11th Oct 2010 10:38 am |
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PaulP
Member Since: 04 May 2007
Location: Barcelona
Posts: 4317
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stapldm wrote:...I see these reports of information as being contradictory.
...As such I think some of the information we are receiving may be less than accurate.
Fully agree Dom
This is something that I mentioned earlier in the thread - it isn't that the information is inaccurate, just that a few of us are seeing slightly different failure modes and symptoms...in fact, they could all be totally unrelated, but the common factor is that at least Renton and I are seeing "clutch slip" under power and when under load.
In my case, command shift helps slightly, but not enough to be sure (i.e. I feel that it slips less in command shift, but haven't done any accurate tests).
I also haven't noticed any juddering as the other guys have.....that doesn't mean that we don't have the same fault, but it could just depend on the severity of the same fault.....or it could be something different
For instance, in my case, I can provoke major slip in 2nd/3rd gears when going up a hill, but it doesn't slip at all when in 6th gear on the motorway.
Yesterday I noticed how, in 2nd gear up a hill, the revs rise to 3100rpm and stay there whilst the D3 accelerates from 25km/h to 40km/h. If I press the pedal further, they will rise to 3400rpm and I can hold it there - in this case the D3 accelerates quicker. If I press less, then it does the same but at 2800rpm with less acceleration.
What does happen though is that upon releasing the accelerator, the revs drop down 400rpm (more or less) when means that when accelerating again, it must take up this "slack" before it starts to accelerate.
This feels similar to the lock-out when the engine/gearbox is cold (although this usually results in the revs dropping to idle which is correct).
As you can see, there are so many ways to describe faults that it's no wonder we can't agree fully on the problems we are having or even if they are the same problem 2006 Discovery 3 TDV6 SE Auto Buckingham Blue
2007 Golf GT DSG
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11th Oct 2010 10:51 am |
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stapldm
Member Since: 11 Sep 2006
Location: Swine Town
Posts: 2330
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Thanks Renton & Paul, makes sense that there are several forms of failures.
The condition you are describing matches with standard non-locking torque converter behaviour, i.e. either the friction surface for the lock-up is shagged, or the actuator is. I've yet to see anything detailed on how the lock-up clutch actuator works; it's as likely a failure point as any and is worthy of investigation perhaps?
In non-locking mode in theory you're getting more torque at the wheels even if you're feeding more pennies to the oil companies.
Found this on Google; worth a look for some high level fill in on the converter assembly for anyone else following:
http://tombirch.com/1/ppt/inspect_torque_converter.ppt 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?
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11th Oct 2010 4:03 pm |
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SteveNorman
Member Since: 14 Oct 2005
Location: Somerset
Posts: 1146
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Lock-Up Clutch Mechanism
The Torque Converter Clutch (TCC) is hydraulically controlled by an electronic pressure regulating solenoid (EPRS4) which is controlled by the TCM. This allows the torque converter to have three states of operation as follows:
Fully engaged
Controlled slip variable engagement
Fully disengaged
The TCC is controlled by two hydraulic spool valves located in the valve block. These valves are actuated by pilot pressure supplied via a solenoid valve which is also located in the valve block. The solenoid valve is operated by PWM signals from the TCM to give full, partial or no lock-up of the torque converter.
The lock-up clutch is a hydro-mechanical device which eliminates torque converter slip, improving fuel consumption. The engagement and disengagement is controlled by the TCM to allow a certain amount of controlled 'slip'. This allows a small difference in the rotational speeds of the impeller and the turbine which results in improved shift quality. The lock-up clutch comprises a piston and a clutch friction plate.
In the unlocked condition, the oil pressure supplied to the piston chamber and the turbine chamber is equal. Pressurised fluid flows through a drilling in the turbine shaft and through the piston chamber to the turbine chamber. In this condition the clutch plate is held away from the torque converter body and torque converter slip is permitted.
In the locked condition, the TCC spool valves are actuated by the electronic pressure regulating solenoid (EPRS4). The fluid flow in the unlocked condition is reversed and the piston chamber is vented. Pressurised fluid is directed into the turbine chamber and is applied to the clutch piston. The piston moves with the pressure and pushes the clutch plate against the torque converter body. As the pressure increases, the friction between the clutch plate and the body increases, finally resulting in full lock-up of the clutch plate with the body. In this condition there is direct mechanical drive from the engine crankshaft to the transmission planetary gear train.
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12th Oct 2010 6:00 am |
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stapldm
Member Since: 11 Sep 2006
Location: Swine Town
Posts: 2330
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Thanks Steve, nice information sheet
So, reading that a failed or sticking solenoid (or its power transistor in the ECU) could prevent lock-up from being achieved too.
ISTR that the gearbox ECU is in the gearbox and integrated with the solenoid actuators, so that's not going to be a fun test for the home mechanic.
Also, the use of pilot hole and pressure differentials to cause the activation (a common enough principle used even in washing machine solenoid valves) does mean that any crud in the fluid could lead to flow issues and a prevention of full lockup being achieved. I can see a full flush being beneficial in this case.
With so many variables this is sadly looking well out of the realms of even an above average home mechanic.
I'm hoping that the experts will give an accurate report to the sufferers above, and we'll learn some more about this "don't be daft, of course it's not really sealed for life" component. 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?
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12th Oct 2010 1:20 pm |
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SteveNorman
Member Since: 14 Oct 2005
Location: Somerset
Posts: 1146
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If you had a sticking solenoid, or incorrect electrical operation, then the ecu would store a code. Yes the ecu is in the box, such as:
P074000 Torque Converter Clutch Solenoid Circuit / Open
P074100 Torque Converter Clutch Solenoid Circuit Performance/Stuck Off
P276100 Torque Converter Clutch Pressure Control Solenoid Control Circuit / Open
P276200 Torque Converter Clutch Pressure Control Solenoid Control Circuit Range / Perf
P276300 Torque Converter Clutch Pressure Control Solenoid Control Circuit High
P276400 Torque Converter Clutch Pressure Control Solenoid Control Circuit Low
If the clutch or torque converter were too bad, then I would expect a
P073000 Incorrect Gear Ratio
or similar for whatever gear you are in, which is set when the slip is too high between input and output shaft speeds.
My money is on the actual friction linings on the lockup clutch juddering, through contamination.
Just my thoughts, as I have no concrete proof...yet.
HTH
Steve
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12th Oct 2010 2:37 pm |
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amondeggs
Member Since: 03 Sep 2009
Location: Telford
Posts: 155
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Right I have more info !
The gearbox specialist have pulled my car apart and tested the fluid in the transmission. Remember this fluid was put in when I had the megaflush by 4tech about 2 weeks ago. They have found the fluid to be water contaminated due to the radiator leaking ATF into the water
The specialist that I am using has had a number of these now jaguars and landrovers are getting to around 5 -6 years old. I thinks we may see more and more of them on the forum.
This means that I need new torque convertor, gearbox rebuild and new rad (or new separate rad) new oil etc etc.. Will cost around £2200 plus Vat. There is no damage to ecu or else it would be more.
Will keep you posted on progress NOT A HAPPY BUNNY
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13th Oct 2010 12:01 pm |
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