Nodge68 said:

That's good as is means I don't have to go outside and get wet to measured my CTS.

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totally of topic as my brain is completely fuddled now lol but regarding rain - Nodge mate - send me some ! we would love some of that rain ! - here are some shots from our farm only an hour ago . Even Barnsley weather would be better than this....


also the bbc news -
http://www.bbc.com/news/world-europe-23810702

Joe

The ect sensor is on its own circuit to and from the ecu. Wires, gray/blue and Brown/green.
Would you be able to fudge another set of wires in parallel to see if it's just the feed that's kaput?
It would be quite fiddly.
Mike

Skinny Mike said:

The ect sensor is on its own circuit to and from the ecu. Wires, gray/blue and Brown/green.
Would you be able to fudge another set of wires in parallel to see if it's just the feed that's kaput?
It would be quite fiddly.
Mike

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If that was the case Mike the 930 wouldn't read the correct temps - that is the key thing ! - also he has metered though the existing loom and also tried a new one.
Joe

Joe_H said:

Hmmm, I have seem those pipes on images I wondered what they were ! - I what else is in the box besides the ecu ? - is there any LIQUID pipes running through this 'box' ? - Can the ecu be placed outside as a jury rig to get it away from the pipes. That again opens up a new aspect. Tell me more about this 'heating' to the ecu box....

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Good question.
The ecm box has the ecm in it!!!!!
But seriously, I can't quite remember. Mines got the tcm, ecm, temperature sensor and another ecu that I cannot recall.
The pipes are literally that, air cooling pipes. No liquid.
And no, the wiring loom would not allow the ecm to be placed outside the box.
Mike

Joe_H said:

totally of topic as my brain is completely fuddled now lol but regarding rain - Nodge mate - send me some ! we would love some of that rain ! - here are some shots from our farm only an hour ago . Even Barnsley weather would be better than this....
View attachment 105266 View attachment 105267 View attachment 105268 View attachment 105269 View attachment 105270

also the bbc news -
http://www.bbc.com/news/world-europe-23810702

Joe

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Ooohhh eck! Thats bad. Had heard about it on the news earlier. Wondered if it was near you.
You know the best way to get it raining is to invite your mates round for a game of cricket and a bbq. Bloody guaranteed to work, over here at least.
Raining here too currently.
Is your farm fairly safe?
Mike

Ok, that seems reasonable, is it possible to remove the top of the box and leave it open ?

Joe_H said:

Ok, that seems reasonable, is it possible to remove the top of the box and leave it open ?

Click to expand...

Yes
Mike

Skinny Mike said:

Ooohhh eck! Thats bad. Had heard about it on the news earlier. Wondered if it was near you.
You know the best way to get it raining is to invite your mates round for a game of cricket and a bbq. Bloody guaranteed to work, over here at least.
Raining here too currently.
Is your farm fairly safe?
Mike

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Hi Mike, We are a few Km's away from the worst at the moment so should be ok, we have grab bags and cat basket ready to go (used to have all this kit on the boat for evacuation !... however, we are reasonably in the clear - and we can see the firestation from here .....

I think BBQ might 'not' - errrr - be a good idea lol that is probably what causes a lot of this ... - every damn thing is tinder dry - it would only take a stray fag end and whoosh !.. (no smokers allowed anywhere near !!!) the smell of the smoke though - it is stinging my eyes -! - another reason for laying off the pop as well is in case we need to get gone quickly! . we usually lock the gates to the drive (well - err rocky long track - our own green lane) but not at the mo.. I aint trying to tackle anything like that ! No way ...

Such is life- feel for the family of the young lass killed - a firefighter ..

Sorry just got back in was outside in the rain putting it together again I can try leaving top off the ecu container to see if any effect but dont think it will as have used freeze spray previously on both the sensor and the ecu casing,.

Skinny Mike said:

Yes
Mike

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Ooooo, ok, back on topic - try that first - leave top off - also make sure that the airflow is really clear and clean so absolutely no hindering of flow to the ecu cooling. If leaving the top of helps, it may be an overheating issue with the ecu - unlikely -but hey - if it needs its own cooling box it must kick out some heat !
Definitely try that next !!! leave top off e box and try it !! -


Oh, and what is this sensor in the ebox ? what does it do ? I cannot see it in a quick search through rave - (I cannot even find the bloody ebox ) .. sometimes freezing spray takes a while to act and you need to get to all sides really.

The pipes are air transfer pipes. The "E" in E box stands for Environmental controled box. It is sealed from the outside world, except for an air feed, supplied by its inboard fan and 35°C temperature sensor, via those pipes. Basically if the box interior exceeds 35°C the fan kicks in, pumping cooling air into the box through one pipe and back out the box through the other pipe.
The pipes terminate in a dry area under the black scuttle panel.

Nodge68 said:

The pipes are air transfer pipes. The "E" in E box stands for Environmental controled box. It is sealed from the outside world, except for an air feed, supplied by its inboard fan and 35°C temperature sensor, via those pipes. Basically if the box interior exceeds 35°C the fan kicks in, pumping cooling air into the box through one pipe and back out the box through the other pipe.

Click to expand...

Hmm, I would definitely leave the top off and test !. the ecu can kick out a lot of heat. lets try that first as it may offer clues to a thermal issue or not.
Leave it off for a day and test.

edit -
Just to add to the above - even if leaving the top of improves things all it does is confirm the already confident diagnosis - I am not suggesting it would or could cure anything.

Joe

IMPORTANT !
Ok, lets all pull back from this for a bit and have a little round the table - I have been pondering and want to reconsider the ecu issue !!!.
The reason is the new info from Nodge regarding the M47 engine coolant temp bypass strategy in the ECU.
Here's why - (and it is late so forgive me if my brain is even more fried.)
From Rave we had the issue where the only info we had was that if the CTS was bypassed the default strategy was to 'trick' the engine into thinking it had a coolant temp of 80C and to put the cooling fans on continuously,
All well and good - so, if the cts was bypassed and the engine started when warm and it was fooled into thinking it was 80C then surely the issue is in the CTS - If the CTS also correctly told the engine it was 80C it should start exactly the same as when bypassed. - if not then we can legitimately suspect the ECU. !. We also had a totally misleading CTS spec sheet from RAVE !. We now know exactly how the CTS system works both external and internal to the ECU and how to test it - so far - no fault found - hence suspect ECU again (due to lack of accurate info and a totally misleading 80C bypass from RAVE which we now know is NOT the case)

HOWEVER ! - from the M47 tech document we now know this is not the case.! -In the event of CTS bypass, then the engine uses a preset figure MINUS 10 C (-10C) as its CTS overide for STARTING ONLY - and then switches to 80C CTS overide whilst running.

This information now puts doubt on the ECU - it does not rule it out - however - I propose the following.

Knowing NOW that the bypass of the CTS cause a minus 10C (-10C) signal for CTS to be given to the ECU - NOT 80C, then we can confidently say that the fuelling instructions on startup / cranking is considerably - in fact very considerably increased by the ECU.
So now with this new info we have the very possible scenario that the issue is actually a fuel supply problem during cranking when warm.
I know this is going around in circles again - but, I think it is only logical to take this new info and apply a little more thought to what may be happening and revisit fuel pressure readings and any other FUELLING aspects that could cause poor starting and look very closely.
We now know that the ECU will command a MUCH longer injector opening time from it's -10C bypass signal (also I suspect use heaters - in a definite way) - this may well be getting around a low fuel supply issue on cranking and allow the engine to start correctly.
With the CTS reading correctly - as it actually appears to be doing - and the fact that the readings from the 930 and the temp gauge seem to back this up, AND the new info re the -10 fuelling signal on starting - then it is time to reconsider.

I have to call it a night and have an early appointment tomorrow. but I want to stress that this new info on the bypass strategy of the CTS may well be extremely important in tracking the issue down.
I know some work was done on pressure testing etc prior to this, and various components have been changed - but - again, lets step back.
If SOMETHING is causing a low fuel supply issue when warm (OR the engine NEEDS a far richer mixture than normal), then the -10 will more than likely compensate (In fact it seems to be doing just that !). Meaning the CTS / ECU may be absolutely nothing at all to do with the problem - a complete red herring - a good one though as bypassing it 'apparently cured' the problem (perhaps the most useful clue along with the added -10 part). We can now fairly and reasonably confidently say that we need to heavily increase the fuel supply / duration signal to allow a warm start.

OP - do not rush out and spend more dosh, you have the 930i, wait a bit and lets get our collective heads together on this.
Please discuss.

Joe

Thanks Joe this does make sense ! The fuel pressure measurements taken so far do look healthy and were pretty much same as brothers car. It has been niggling me though that I have never taken compression tests. Its not something I have ever done and I don't have the tool to carry it out. The i930 does not seem to have an option for that in its limited armoury either. I am guessing its something that must be done manually by screwing a gauge into glow plug hole ?
I suspect the increased fuel etc triggered by removing sensorplug could perhaps compensate / mask a compression issue. ?

I am guessing any compression issues are likely to be an expensive repair and that's something that has been playing on my mind.
I don't want to get ahead of myself but fearing the worse I have been thinking of a plan B if there actually is a piston/cylinder problem.
Could it be a workaround to incorporate a switch into the coolant circuit ? My thinking is that to start the car I could flick a switch to disengage the CTS and flick back once started. Not ideal but could avoid a great expense.
I suppose there is nothing to suggest a compression problem yet as it runs fine but I wont sleep tonight now

REDNAL3 said:

I am guessing any compression issues are likely to be an expensive repair and that's something that has been playing on my mind.
I don't want to get ahead of myself but fearing the worse I have been thinking of a plan B if there actually is a piston/cylinder problem.
Could it be a workaround to incorporate a switch into the coolant circuit ? My thinking is that to start the car I could flick a switch to disengage the CTS and flick back once started. Not ideal but could avoid a great expense.
I suppose there is nothing to suggest a compression problem yet as it runs fine but I wont sleep tonight now

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Hi Rednal. there is no evidence at all that I have seen or read or postulated that would lead me to suspect compression issues.
Speak later,
Joe

I had been thinking possible HPFP, but the pressure readings don't support that idea.

Nodge68 said:

I had been thinking possible HPFP, but the pressure readings don't support that idea.

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Hi Nodge, I have been looking at some issues with 2.5 BMW engines with similar issues (well, same issues really). The problem seems to affect VW and Audi models as well... Struggling to start when warm. Problems seem to be wear in the HPFP.
One think we havn't determined Nodge is the actual cranking pressure of the HPFP on no start - compared to cranking pressures on hpfp when it starts ok
There were some quick checks done before - when it wouldn't start. but it doesnt sound like it was done in a comparative way. One major difficulty is assessing cranking pressures when it starts ok as it fires immediately so extremely difficult to make any comparison.

According to several forums about similar issues with a similar setup -
This is the test to try to determine HPFP wear - (A bit crude but none the less worth trying
(Might as well do the 930 checks and record them at the same time from a total cold start and then from a warm attempt)
So, 930 on - start from cold - will start normally it seems.
Warm engine up - take it for a run up to normal temps - try to start it a few times and check with 930 again and note all pressures. Dont keep going unitl it starts this time.
Now the bit I think is great - to check for wear in the HPFP get a garden hose and let it pour water over the hpfp for a few minutes to cool it down properly (2 or 3 minutes) - and then try again. If it starts ok now then it is related to the hpfp temperature.

Give it a go, nothing to lose and you can log the data at the same time.

Joe.

I have been trying to ascertain exactly what temperature window gives the starting issues and also to get coolant reading when needle sits at mid way point.
i can confirm the coolant needle reaches dead centre at 80 degrees,It seems to be an easily cooled engine whilst driving probably given the size of grill. It kind of almost hovers just slightly below mid way point. Anyway to get it to that mid point i had coax it by revving it stationary for a minute.
I now believe the starting issues occur when coolant is between 13 and 67 degrees. If out with these readings the car will start first time..
For example at 9.30am this morning the coolant was 16.4 degrees. I knew before even trying it that it would take multiple attempts to start and this was indeed the case. I drove it until it got to 57 degrees let it sit for 5 mins and tried to start it. It only just started but cut out within a second of doing so.
I drove it again up to 69.35 degrees turned it off and it restarted no problem. I drove it further up to 76 degrees turned it off and again restarted perfectly.
I let it cool until 61 degrees. It only just started but cut out within a second of doing so. Not sure if temperature range is significant but thought a worthwhile exercise.

Try the HPFP hose pipe test in your 'no start' range.
Then we can look at your figures and temps, IF INDEED those temp windows are accurate and definitely repeatable then we will go from there.

Joe