Neptune19522 said:
I was advised by the chap who looked after the Engine ECU, at JLR, that throttle peddle pressing was not required upon starting up and up to the insertion of this replacement engine ECU I have never needed to press the throttle upon starting. Experience in the past, post fitting replacement ECU, was that any attempt to press the throttle before full revs was established just delayed that hiccup before full throttle authority was available. The engine now starts up in a slightly 'lumpy' mode then settles down for a little with a slight increases in revolutions until that hiccup which has, pre ECU change, occasionally stalled the engine - usually on cold days i.e. around 4deg C to -1deg C or lower. Frustrating but not a problem. I think the problem has always been there. On reading the Rave item on auto gear boxes I note that any faults that have not been repeated, within 40 cycles, are deleted. Perhaps I should just drive it and wait for 40 cycles?

I acknowledge your description of 'interesting' however I apply the epithet of 'infuriating'... Still if it was easy everyone would be doing it!
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Pressing the throttle is suggested for diagnostic purposes only - to get a recording of Accel. 1 to 3. which could give a clue to the problem.

It may be worth looking at RAVE 18-1-18 and 18-1-19 particularly the bit in green on 18-1-19 which says replacement ECMs are configured for 2 track TPS and need to be reconfigured for 3 track TPS which you have. This may not apply to your secondhand ECM particularly as it is recognising track 3, but any straw is worth clutching.

Just to reconfirm, was the fault present with your old ECM before it failed??
 
Neptune19522 said:
I was advised by the chap who looked after the Engine ECU, at JLR, that throttle peddle pressing was not required upon starting up and up to the insertion of this replacement engine ECU I have never needed to press the throttle upon starting.
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Not that the throttle is not required on start up but it's 100% "counterindicated" as i mentioned some time ago in this thread
 
I have tried three starts. The first I 'pumped' the throttle continuously until the eighth pump when the engine burst into life; OK so far. Then I started the engine again after a pause. I pushed the throttle full down and cranked the engine; I could not get my foot off quick enough as it burst into life! The third start was almost the same except I did not push quite so hard. I do remember that on one vehicle the starting procedure involved a full pump of the throttle, down and up, before cranking, (I have yet to try this on the Disco2). I think it was an Austin Morris vehicle but it could be the same engineers in powertrain. Not sure if I like this approach as the engine initially rev up to very high revolutions; I do not like high revs until the engine has run for about five minuets to allow full oil circulation.

Thoughts please? And perhaps you could explain your own starting protocol to compare notes?

I did create some files but my niece has gone home which means I may fumble to go via my old MS OP system laptop before transferring direct to my Mac; time will tell!
 
I actually managed to produce the files! I hope these two, no idea what happened to the third, are of use!
 

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Neptune19522 said:
And perhaps you could explain your own starting protocol to compare notes?

I did create some files but my niece has gone home which means I may fumble to go via my old MS OP system laptop before transferring direct to my Mac; time will tell!
Click to expand...
 
Neptune19522 said:
... And perhaps you could explain your own starting protocol to compare notes?

I did create some files but my niece has gone home which means I may fumble to go via my old MS OP system laptop before transferring direct to my Mac; time will tell!
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Briefly, nothing interesting on starting procedure, I just turn the key, no throttle, it starts and I wait for the oil light to go out. Throttle response is immediate if necessary.
 
You were describing my start up procedure before the ECU failure. I am concerned that I may have to start under full or very high throttle as my oil light takes a few seconds to extinguish. I wonder it my problem is oil pressure related. By the way I have an automatic gear box which attracts the quite rare engine ECU; which include the cruise control. Lots of manual ECUs available but not so many of my NNN500030's
 
Neptune19522 said:
I actually managed to produce the files! I hope these two, no idea what happened to the third, are of use!
Click to expand...
Well, looking at AD004, the ECM was “seeing” your throttle input (your right foot!) but not responding to it which is odd. Also you have just said this issue only appeared after your original ECM failed points to your new ECM being the problem. What do you know about it? Was it remapped, was it guaranteed fully working etc etc??
 
I have always had a small delay, more so on cold days; which is where my theory about having two maps - one for starting and one for running. However Fery has debunked that idea. The delay was at most about 10 seconds now, or before I tried this full throttle start, 10 seconds is about the shortest delay I have experienced. I did think my throttle was misbehaving but a cold check, using Nanocom, with no starting involved showed that the throttle was apparently working correctly - zero with foot off and 99 with foot down full. I have assumed that the throttle pot is working correctly. Without another engine ECU to try on my vehicle and given the scarcity of the auto box ECUs this would appear to be impractical in practice.
 
Neptune19522 said:
You were describing my start up procedure before the ECU failure. I am concerned that I may have to start under full or very high throttle as my oil light takes a few seconds to extinguish.
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I insist, dont touch the throttle while cranking unless it was completely out of fuel cos you might end up with a hydrolocked engine, if it doesnt start without throttle you have to find out why and fix it, dont insist with the throttle which as i said more times is highly unrecommended ... next time turn ignition on 2 push the throttle down 5 times consecutively then wait for the MIL to stop flashing then crank it without touching the throttle... if it doesnt start right away there is a problem with the fuel supply, possibly leaking injector copper washers or something which lets air in the fuel rail... replace the air bleed valve in the filter head if it wasnt changed yet to be ruled out thenrepeat the 5 throttle purging trick.
 
I think we are singing off the same hymn sheet in that I am unhappy with a full throttle start as the oil has not enough time to get around all of the engine. I stated above that I have read somewhere that the throttle should be pumped once before foot off and crank. You suggest two pumps and I think this is something I will try tomorrow as I want to start this engine, without delay, from cold. Once I can start without that awful 120 sec delay I will consider this vehicle ready for regular use! I will need to experiment with the start but you can rest assured I will not start with my foot down on the throttle; far too much potential damage!
 
You misunderstood my point i think. I said it's completely unrecommended to touch the throttle on a Td5 before or while cranking as long as it didnt run out of fuel and i said
sierrafery said:
next time turn ignition on 2 push the throttle down 5 times consecutively then wait for the MIL to stop flashing then crank it without touching the throttle.
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the MIL should flash for up to 3 minutes and that's a test to see if the probem is fuel supply related or not cos that 5 throttle trick is actualy a purging action so after that the fuel must be free of air and with proper pressure in the rail if you see what i mean...forcing the throttle on start up can end bad for the engine and doesnt rule out anything, it's just prooving that something is wrong and what ever the cause of that symptom of your's is it must be fixed as the engine to start and idle well with no throttle at all
 
Neptune19522 said:
I have always had a small delay, more so on cold days; which is where my theory about having two maps - one for starting and one for running. However Fery has debunked that idea. The delay was at most about 10 seconds now, or before I tried this full throttle start, 10 seconds is about the shortest delay I have experienced. I did think my throttle was misbehaving but a cold check, using Nanocom, with no starting involved showed that the throttle was apparently working correctly - zero with foot off and 99 with foot down full. I have assumed that the throttle pot is working correctly. Without another engine ECU to try on my vehicle and given the scarcity of the auto box ECUs this would appear to be impractical in practice.
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As we seem to have confirmed the fault was there to a greater or lesser extent with the old ECM this would probably exonerate the new one. This would point, as Fery said, to injector seals, very common, etc.
 
in addition to my last reply
PopPops said:
Well, looking at AD004, the ECM was “seeing” your throttle input (your right foot!) but not responding to it which is odd
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it's not very odd as long as there is not enough fuel at the injectors at that very moment which is a sign of fuel supply issue cos without fuel the engine will not respond despite of the driver demand, it's like when you want to accelerate with empty reservoir... it can be bad air bleed valve or leaking injector washers , these are the most common but it can be something more perverse too
 
sierrafery said:
in addition to my last reply
it's not very odd as long as there is not enough fuel at the injectors at that very moment which is a sign of fuel supply issue cos without fuel the engine will not respond despite of the driver demand, it's like when you want to accelerate with empty reservoir... it can be bad air bleed valve or leaking injector washers , these are the most common but it can be something more perverse too
Click to expand...
Yes, I agree, but we seem to have been led to believe the fault only occurred with the new ECM, which is what I had been assuming, but it seems to have been present before, so it's now a "new" fault to trace, not the original ECM failure.
 
I have looked at the workshop manual and it is very poor in that there is just a description with little or no information regarding repair and replacement of the injectors. Apart from requiring several special tools little is written about the injectors at all, not even any torque settings! I have changed injectors in the old series engines, Gem 200 and Gem 300 but to date I have not touched a Td5. Injectors require almost clinical cleanliness with hospital operating room type conditions prevailing so I am very hesitant about just pulling them out and using one of the many 'O' rings I have in my garage to replace these, possible, faulty seals. I do have a selection of copper washers but again I suspect the absolutely 'right' one is required. I only have experance of my own Q2 so what is the likelihood of these 'O' rings and washers failing?

Before I take off the acoustic cover could you direct me to any information about how to set about changing these five washers and 'O' rings? I will, I presume, need to source replacement parts and defiantly not from China!
 
Neptune19522 said:
I have looked at the workshop manual and it is very poor in that there is just a description with little or no information regarding repair and replacement of the injectors. Apart from requiring several special tools little is written about the injectors at all, not even any torque settings! I have changed injectors in the old series engines, Gem 200 and Gem 300 but to date I have not touched a Td5. Injectors require almost clinical cleanliness with hospital operating room type conditions prevailing so I am very hesitant about just pulling them out and using one of the many 'O' rings I have in my garage to replace these, possible, faulty seals. I do have a selection of copper washers but again I suspect the absolutely 'right' one is required. I only have experance of my own Q2 so what is the likelihood of these 'O' rings and washers failing?

Before I take off the acoustic cover could you direct me to any information about how to set about changing these five washers and 'O' rings? I will, I presume, need to source replacement parts and defiantly not from China!
Click to expand...
I have only just changed the injector seals on mine and it is not a particularly difficult job. I spent more time than probably necessary cleaning the seats and general fettling and being very over cautious, but it is about a 1/2 day job. There is a very good description here: http://www.discovery2.co.uk/Injector Seals.html

He gives part numbers and only use genuine seals, even if ~£5 for a copper washer seems expensive, genuine only. As per RAVE I also replaced the rocker bolts and, going OTT also the injector clamp bolts as they are the same grade as the rocker ones torqued to the same value. The copper washer seals on mine were in quite good condition (153k miles) with no signs of leaking, but I did the job as I suspected the O rings. The only "special tool" you may want is the injector puller. I bought one a couple of years ago when I saw it cheap on eBay. Most use a modified allen key or water pump pliers, but I'm glad I had the right tool.

Most of the online parts suppliers stock what you need.

Have a look at the link and see what you think.
 
Neptune19522 said:
Before I take off the acoustic cover could you direct me to any information about how to set about changing these five washers and 'O' rings?
Click to expand...
see this http://www.discovery2.co.uk/Injector Seals.html and you dont need that special tool you can use a large L shaped allen key or improvise with what you want as to be able to lever them out like this guy (i dont understand what he sais but it's the shortest way to have an ideea)

 
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Just tried a, cold engine, start with two throttle depressions and it started but there is still a 21 second delay before throttle authority. Either these two depressions worked or it was quite warm in my unheated garage. A third possibility is that the ECU is learning and accepting the conditions under it is now working, in other words it is learning the new vehicle it is in! The injector problem is not being ignored however the price of after market washers and seals is a tenth of the OME items; sounds like JLR strategy...

Having trouble with this thread, See
"Vehicle will crank but not fire! Thread 2" Essentially I have started another thread as this one seemed reluctant to go any further. Ken
 
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