Its in the no start range at moment and I'm happy to try the garden hose exercise now.The neighbours already think I'm nuts anyway. I will have to soak it from bonnet or wheel arch as under carriage and sump guards in place. Where is the high pressure pump exactly ? I replaced seal on the high pressure sensor previously. Is that the actual pump it is screwed into or is it sited elsewhere?
 
Its in the no start range at moment and I'm happy to try the garden hose exercise now.The neighbours already think I'm nuts anyway. I will have to soak it from bonnet or wheel arch as under carriage and sump guards in place. Where is the high pressure pump exactly ? I replaced seal on the high pressure sensor previously. Is that the actual pump it is screwed into or is it sited elsewhere?
lol :)
Yes, thats the beasty - the cool whole pump block - probably make no difference but hey ... :) keep the neighbours happy - you dont have to blast it :eek:- just run water over it over a few minutes. - oh - HANG ON _ you replaced the seal on the HP SESNOR - or the HP REGULATOR !!! = it is where the regulator is attached to - the big lump..
 
Ok gave it a good cold water soaking for 4 minutes but no joy with starting. :( Coolant temp is at 41 degrees just now. I also gave ecu casing a good spray with freezing spray over both sides of casing. Gave it a minute to work and tried to start. Again no joy but worth a try
 
Sorry missed you comment. Yes I have replaced high pressure sensor seal and also replaced the high pressure rail regulator. The HP pump I just soaked sits just behind alternator
 
Ah well, that rules that out :) - at least you can cross that off as a source.
Did you make a note of the pressure readings during the no start again this time ? - also, is the glow plug light coming on at all before you try to start it ?
 
Ah well, that rules that out :) - at least you can cross that off as a source.
I would doubt that water from a hose is below 13°C at this time of year. It might not have cooled the pump enough;)
The glow plugs come on when the coolant is below 15°C I think.
 
Yes Im sure glow plug light comes on and extinguishes as normal every time. I am heading out just now so can check that.
The pressure readings before starting are low pressure 370-385 and high pressure zero. I dont think the high pressure reading kicks in until you actually try to crank isn't that correct ?
While cranking it reads 40 - 60k . The i930 probably isn't great for this live cranking data but still adequate
The hp will have residual reading between cranks of about 2k. Once it starts the high pressure quickly levels off to between 29 900 and 30 800 try to start and low pressure 366
 
These readings are from just now during poor starting episode. I will add the readings again once its up to temperature
 
The running pressure seems ok, the cranking pressure seems crazy high to me ? - I cannot see how it could be that high but have nothing to compare it to...
 
Yes Im sure glow plug light comes on and extinguishes as normal every time. I am heading out just now so can check that.
The pressure readings before starting are low pressure 370-385 and high pressure zero. I dont think the high pressure reading kicks in until you actually try to crank isn't that correct ?
While cranking it reads 40 - 60k . The i930 probably isn't great for this live cranking data but still adequate
The hp will have residual reading between cranks of about 2k. Once it starts the high pressure quickly levels off to between 29 900 and 30 800 try to start and low pressure 366

Those HPFP pressures look absolutely fine. 40K + in cranking is ideal.

The glow plugs should only come on when the coolant is cold. Do your plugs come on every start?
 
These readings are from just now during poor starting episode. I will add the readings again once its up to temperature
Trouble is when it is starting ok you will not get a cranking pressure as it will start immediately :(

Non if this is making any sense at all.
 
Those HPFP pressures look absolutely fine. 40K + in cranking is ideal.

The glow plugs should only come on when the coolant is cold. Do your plugs come on every start?
Ok Nodge, if you reckon that pressure is ok then fair enough - I have never tested a TD4 pressure. No worries
 
Ok Nodge, if you reckon that pressure is ok then fair enough - I have never tested a TD4 pressure. No worries

When I had a random bout of bad running a few months back, I did all the tests. I looked at live data when starting, idling, cruising and flat out. Mine showed 40 to 50Kpa while cranking.
 
When I had a random bout of bad running a few months back, I did all the tests. I looked at live data when starting, idling, cruising and flat out. Mine showed 40 to 50Kpa while cranking.
Excellent, that is a superb reference - it would be difficult to obtain otherwise ! :)

Unfortunately - this is all heading back to the same issue - the ECU - we can do a good test if the actual temp window figures of no start are truly repeatable - that is to put a resistor across the CTS plug to make the engine believe it is 80 F when it has actually cooled to where it doesn't start (in the 60C range)

edit - looks like a 220 ohm should do the job - check it with 930 on the cts sensor plugged in first - read temp (say 60C whatever (in the no start window)- then unplug - fit 220 ohm across the plug and don't connect to cts ! - check temp now - if it was - say 60 on the cts, it should read around 80 - 100 on the 220 ohm (depends on the NTC curve but it will be near enough and the 930 will read what it THINKS it now is - which is what the ecu is seeing now.
Joe

somewhere between 220 and 330 ohm would be fine.
 
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This should allow you to set any temperature you want from around 5C to 120C.
There are only 2 components, a 4.7K ohm Pot (Linear) and a 100 ohm resistor. - wire as shown - connect to cts PLUG (leave CTS sensor disconnected)
It can go to the plug any way round. Insulate it from shorting to ground (bit of insulating tape around the bits)
The 100 ohm resistor is important - it acts as a simple buffer when the pot is at the end to make the minimum resistance no less than 100 ohms.
The POT will be quite sensitive as the setting is increased to provide a higher temp reading to the ECU . (you could chose to use a logarithmic taper pot which would help with the sensitivity but I wouldn't - no worries either way) - You can check what 'pseudo' temperature you have actually set it to with the 930 diag. - ie - adjust pot - read diags - that's the temp the ecu is seeing. No worries.
You can then confirm if there actually is a cut off point (window) . It will move the gauge as well.
(Excuse the spider scrawl :rolleyes:) - I couldn't find the back of a fag packet ;)

Would also work on K series and L series....

TD4 CTS_ECU tester Joe H 2016.JPG


Joe :)
 
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Wow just returned home you guys have been busy :D:D
Firstly yes absolutely correct there are no HP readings when starting is ok. It simply jumps straight to 28800 with car running.?
I have been checking whilst out and the temperature starting windows still running true. Id like to sense check lowest figure so hopefully it gets down to 13 degrees overnight.;) I didnt see glow plug light this afternoon. Its 17 degrees here at moment so perhaps as Nodge says it only appears at 15 degrees or below. Ill check later..
I'm not familiar with the components in above diagram but good at following instructions. Failing that hopefully Maplins guy can rig me something up if I show him .;)

.
 
This should allow you to set any temperature you want from around 5C to 120C.
There are only 2 components, a 4.7K ohm Pot (Linear) and a 100 ohm resistor. - wire as shown - connect to cts PLUG (leave CTS sensor disconnected)
It can go to the plug any way round. Insulate it from shorting to ground (bit of insulating tape around the bits)
The 100 ohm resistor is important - it acts as a simple buffer when the pot is at the end to make the minimum resistance no less than 100 ohms.
The POT will be quite sensitive as the setting is increased to provide a higher temp reading to the ECU . (you could chose to use a logarithmic taper pot which would help with the sensitivity but I wouldn't - no worries either way) - You can check what 'pseudo' temperature you have actually set it to with the 930 diag. - ie - adjust pot - read diags - that's the temp the ecu is seeing. No worries.
You can then confirm if there actually is a cut off point (window) . It will move the gauge as well.
(Excuse the spider scrawl :rolleyes:) - I couldn't find the back of a fag packet ;)

Would also work on K series and L series....

View attachment 105320

Joe :)

This would be my next move too.
You can test if the non starting is an actual temperature related issue. Or an ECU received temperature temperature issue.
 
If you can get someone to knock up this little test rig, then you can fool the ECU into thinking the engine is any temperature you like.
 
Wow just returned home you guys have been busy :D:D
Firstly yes absolutely correct there are no HP readings when starting is ok. It simply jumps straight to 28800 with car running.?
I have been checking whilst out and the temperature starting windows still running true. Id like to sense check lowest figure so hopefully it gets down to 13 degrees overnight.;) I didnt see glow plug light this afternoon. Its 17 degrees here at moment so perhaps as Nodge says it only appears at 15 degrees or below. Ill check later..
I'm not familiar with the components in above diagram but good at following instructions. Failing that hopefully Maplins guy can rig me something up if I show him .;)

.
Maplins guy will sort you out no worries at all - nothing critical on it at all - all low v low current stuff - 1/4 W resistor for the 100 ohm - any type of pot of the correct value (4.7 K ohms is a standard value) - add a couple of meters of twin cable (car speaker wire is ok) and you can bring it into the car through the window - solder the ends of the wires to allow them to push into the CTS plug.

You cant even do any damage with it whatever you do so have no worries. The ecu output is at least a 1K resistor so you could actually accidentally ground it and it wouldn't matter - ie - you could accidentally short the CTS plug terminals together and it won't hurt anything.
Joe
 
Here is a slightly better version (the other one is perfectly ok just that the adjustment will be very coarse - which is fine for most things) - this one allows much much finer control allowing a specific temperature (within a couple of degrees) to be set far easier - range will be around -10C to +125C ('Mil' spec version lol :cool:;)) - you have two knobs instead of one - you will soon see how it works :) - the 10K pot will adjust the colder temps with the 1K at max, then with 10K at min, the 1k will adjust the high temps in a much finer way (and any setting in between is usable) - just twiddle them and read the temps with the 930 (with engine off but ignition on of course) and you will see how it works in about 10 seconds - then start it with setting you desire. Adjusting it wildly with engine running will make the ecu car sick :D:eek: and go into backup mode until next ignition cycle.
If anyone wants more details how it works or how to use it - just let me know.
cts test 2.JPG


Joe
 
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