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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266   
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i am married ... but she's VERY understanding.
I understand the various parameters you mentions could and probably are different but would they impact on performance / noise notably when the parameters are very nearly the same ie 1 hill a few minutes down the road from the previous one or the same hilll but a diffeerennt day? I hopefully be proven wrong........no actually I hope to be prove myself right actually...?? ... ??  
I just can't see it - can the defender really be that different.....it is basically a transit van / modeo engine and I've never known anyone to complain about them performing differently from day to day - something just doesn't seem to 'stack up'? |
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5th Nov 2013 11:13pm |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266
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actaully ...... I need a sanity check here.
noise from engine, sounds like bag of nails while towing caravan up hill - no all is fine sir - turns out heat shield and support braket has bolts missing - diagnose and fix myself noise / clatter underload - no all is fine sir - input shaft fails oil leak - no problem sir we'll replace oil seal oil leak - no problem sire we'll replace oil seal oil leak - you must be having a laugh (or puting oil on transmission as the oil levels are all ok)........new gearbox fitted last defender noisey engine can't be right - no all fine sir we've even taken it for 100mile test drive..........new injectors and pump fitted by new owner ! either I'm a complete muppet, unlucky or dreaming (possibly dreaming most of the time now as this is all starting to make me hit the bottle). |
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5th Nov 2013 11:20pm |
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| lambert.the.farmer Member Since: 11 Apr 2012 Location: harrogate Posts: 2006 
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Since the last cambelt died and ate another set of push rods I haven't been able to trust mine, it makes noises it never used to and is more rattley than I remember. However it still works and goes as well or better than ever so until the motor explodes in a shower of big end shells and con rods I will live with it. Worrying is counter productive. Rhubarb and custard let fly with their secret weapon.
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6th Nov 2013 6:44am |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266
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tatra805,
you've mentioned you had limp mode when your turbo wasn't working correctly. can you tell me if this also brought the MIL on or not? as I've suspected for sometime, not just on this topic but elsewhere there's been an intermittent fault. will intermittent has now become permanent and I'm told it's the turbo. I suspect this like ownership for the last 3 years is anything to go by getting it resolved by LR is going to be a very big up hill struggle.  |
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11th Feb 2014 10:20pm |
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| Skye_Rover Member Since: 30 Aug 2013 Location: Skye Posts: 85  
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Caterham, if the fault is recognised long enough to trigger a limp-home reaction, then you should have a MIL illuminated on your dash. The threshold to determine whether the turbo is reacting, or not, is dependant on engine speed and the like, and there is a further time-dependant component that will have to be fulfilled before a MIL (and limp-home) is flagged. There are separate fault checks for the vane control and closed-loop manifold pressure control, and each of these is tuned at the calibration development stage of the programme to be sufficiently "loose" to allow the Defender to work in all environments without falsely flagging a problem.
However, this isn't to say that you have had perfect turbo response all the time; because the fault reactions are tuned to wait a while (for high altitude operation, where turbo response is more sluggish than at sea-level), you could be experiencing a bit of low boost through a partially-sticking vane control - not enough to flag a fault, but enough that you could feel the engine performance being a bit lacking. If you log the MAP (manifold absolute pressure) over the OBD2 diagnostic socket with an OBD2 compatible tool or better, then it is possible to compare your vehicle to a "known good" Defender operated in the same sort of way. The trouble with vane sticking is that it can vary a bit from measure to measure, and you need to compare apples with apples - same acceleration in the same gear from the same engine speed. There are standard tests that I can dig-out if you need a "known good". Roads? Where we're going, we don't need roads. |
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11th Feb 2014 11:18pm |
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| martinfiattech Member Since: 13 Nov 2013 Location: leicester Posts: 422
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I missed all this, how have they now found the turbo faulty has it just been under boosting, surely a road test with a computer showing boost pressure required and actual, mass air flow req and actual, turbo vane actuator position as previous along with egr . its not hard its the first thing I do at work and if I get a fussy customer these are mostly motorhome owners who a lot of the time don`t go over 2500 rpm.
I had one guy who had never gone past 2500 rpm and was moaning about lack of power on a 3.0 180hp fiat 1 dpf regen later a good high speed run it was a different van, the amount of soot that came out of the dpf was amazing I`am still surprised the ecu let me regen it 270 % soot loading . |
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11th Feb 2014 11:21pm |
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| Skye_Rover Member Since: 30 Aug 2013 Location: Skye Posts: 85
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"the amount of soot that came out of the dpf was amazing I`am still surprised the ecu let me regen it 270 % soot loading ."
So am I !!! But you knew what you were doing, and that was fine - normally Fiat are pretty sussed about their strategies, thermal protection included. A fair point though. First thing I would do, if I measured a slow response on the vanes at their limits, would be to run a decent cleaner through the intake system to purge whatever I could from the vane mechanism. This is less of an issue with Defender than with Disco3, where turbo access is just awful, as you can get to the unit to clean it manually with a solvent. This has saved two D3's from going on transporters to have the bodies lifted, 8hours labour at a time, in the main dealers, as I don't have the 2-post ramps to do this job (yet), only 4-posters. In both cases, normal turbo operation was restored for over 12months (to-date). It is not a cheap option at £50 a shot, but that compares with a bill of £900 just to get the turbo off a D3. Roads? Where we're going, we don't need roads. |
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11th Feb 2014 11:45pm |
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| landy andy Member Since: 15 Feb 2009 Location: Ware, Herts Posts: 5429 
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On a side point, disco 3 turbos can be removed without body lift by cutting the studs then replacing with bolts.
Andy |
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11th Feb 2014 11:53pm |
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| Skye_Rover Member Since: 30 Aug 2013 Location: Skye Posts: 85
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True....but they're still a bit tight, even after all the heatshields have been bent/ripped/removed and deposited in the metal bin
 I always worry about leaving the remains of the fixings behind in the manifold; I saw a few early engines left with scrap manifolds after the turbos had "seen a bit of action" before packing-up, all because fitters couldn't get the last bits out in-situ. And you don't want to have to change a manifold...
Still, no worries like that on Puma in Defender. A good dose of Mr Muscle, AKA "the VAG Diesel cure" soon has things moving again  Or you can go the "kind" route and use something along the lines of one of those intake system sprays, which I have found to work in each case. Much less to go wrong. Roads? Where we're going, we don't need roads. |
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12th Feb 2014 12:28am |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266
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Sorry I've not responded sooner but busy doesn't start to describe how things have been...was ill yesterday as a result.
Any how after being told turbo was at fault and discussing with LR who agreed to fix when I collected Def it was working 
So obviously didn't want to take to LR without fault.....tried to generate fault so with foot to floor took it to 3k rpm several times and no problem at all
Took to 4k rpm and limp mode but no mil.... Next day limp mode had gone after a few short journeys in limp but then shortly after start of next journey limp and mil light!! Def now at dealers awaiting diagnosis / replacement turbo. Last edited by Caterham on 19th Feb 2014 8:32am. Edited 1 time in total |
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18th Feb 2014 10:20pm |
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| ericvv Member Since: 02 Jun 2011 Location: Near the Jet d'Eau Posts: 5816  
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^^....when I collected Def it was working
.....tried to generate so with foot to floor took it to 3k rpm several times and no problem at all Took to 4k rpm and limp mode but no mil....
Caterham, that sounds like a deliberate attempt to destroy something which apparently worked. And not all on this forum may be happy to read such things. It also won't help to stretch your fuel consumption to any further records...  You never actually own a Defender. You merely look after it for the next generation.
http://youtu.be/yVRlSsJwD0o https://youtu.be/vmPr3oTHndg https://www.youtube.com/watch?v=_GtzTT9Pdl0 https://www.youtube.com/watch?v=ABqKPz28e6A https://www.youtube.com/watch?v=rLZ49Jce_n0 https://www.youtube.com/watch?v=XvAsz_ilQYU https://www.youtube.com/watch?v=K8tMHiX9lSw https://m.youtube.com/watch?v=dxwjPuHIV7I https://vimeo.com/201482507 https://www.youtube.com/watch?v=ZSixqL0iyHw |
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19th Feb 2014 5:54am |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266
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19th Feb 2014 8:32am |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266
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well turbo seems to be working a treat. old one didn't have any obvious signs of carbon build up however the service manager brought my attention to the fact that the fan spindle had quite alot of play in it? there was certainly far more than I would have expected but with no oil in it and nothing to compare it to I can't really say. anyhow hopefully over the w/e I'll get to do a few miles and report back. hope you all have a good weekend.  |
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28th Feb 2014 11:20am |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266
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as mentioned above my faulty turbo had alot of play in the fan spindle. compare it to another an there was no detectable play what so ever.
my question therefore is could this play have been there since day one / is it likely to have been there since day one and if not what is likely to have cause this to become loose? |
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12th Mar 2014 8:55am |
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