Help Can anyone confirm all starting related components and requirements ?

Hi mate, yes, they were anticipated and based on everything I believe that they finally do confirm the ecu is faulty.
It is actually quite good that the cts can be unplugged and can be re-plugged.
You could make it fully automatic, but for now, just cut the slate / blue wire (white and blue) - extend them into the cockpit and attach to a small switch.
Switch open - start - switch closed - run
As said, later when you are happy - and after a few months and no other issues arising - we can make it fully automatic.

Nodge68 said:

I hate to say it, but either your non starting is random, or I think it's an ECU fault.
However you plugging in the sensor while the engine is running has confirmed that you can rig a simple switch to force a start every time.

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Hi Nodge, we replied at the same time - I dont believe it is random. - it is predictable. Once the engine is up to normal temps it will start at any fudge setting below that temp, but will not start if the actual is below normal operating and above around 14 15c - that is fully predictable.
If the ecu 'thinks' it is 70C, but it is not actually - it will not start. That signifies to me that the ECU is not applying a correct starting fuel mixture unless hte engine is very low temps. Above that (low temp starting point) it appears to only be signalling enough fuel for an engine at normal operating temps - no inbetween. But, as soon as it starts, it is signalling the fuelling correctly.
It appears to come down to a cranking fuelling issue within the ecu where it is only giving a heavy start mix at <14 / 15C - anything above that it is giving a narrow injecotr pulse (or to put t another way - very little fuel) during cranking - only enough to start it at normal operating temps .
Winding the temperature up to 100 C is probably making fuel quantity even less !! - hence no start at the higher signalled temps.
I believe the ecu is operating as normally WHEN RUNNING - but is completely captain cooked during cranking - and in a repeatable way.

If it starts when it thinks engine temp is cool and doesn't start when it thinks engine temp is warm then this to me points to a compression issue on the engine and it overcomes this low compression with glow plug usage at lower coolant temps

Apologies if I've got the logic wrong in the above statement

Nodge68 said:

Two things Joe.
There must be a fuel path from the LP to the HP as it's possible to see fuel at the leak back pipes while only the LP pump is running. Mine all leak back about 10mL in a minute. I know this because I tested it when I had that bout of misfiring a while back.

The Synergy plugs into two locations on the engine. There's a connection to the fuel rail sensor and another connection to the MAF sensor.
I also have a boost box fitted, this plugs into the MAP sensor.

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Interesting Nodge, Yes, On closer examination of the pump there appears to be a HP one way valve arrangement on each of the three plungers (the delivery ball valve)
Also an inlet (fuel suction valve) which acts as a one way path from LP to HP on the suction stroke. This arrangement would allow LP through to the HP when the pressures had equalised as the HP residual reduced. The suction valves would effectively be 'floating'. No HP could return though due to the delivery ball valve.
I am quite amazed that you got 10 mL in a minute on the LP pump only ! - Have you ever seen a spec for that system ? - On other common rails I have worked on a figure of around 10ml per minute at idle. certainly NOT on LP. - Have you any documentation that satisfies you that the leakoff on LP only on that system is normal - (Isn't the pump a CP1 or derivative ?)
Thanks for the info nodge
Joe

td4van said:

If it starts when it thinks engine temp is cool and doesn't start when it thinks engine temp is warm then this to me points to a compression issue on the engine and it overcomes this low compression with glow plug usage at lower coolant temps

Apologies if I've got the logic wrong in the above statement

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Hi TD4Van, it does start every time when the engine REAL coolant temperature is above mid 60's C.
It also starts fine when the REAL engine temperature is BELOW about 15C.
Above 15 C ACTUAL coolant temp and Below mid 60's ACTUAL coolant temp it will not start without major cranking.
If it is genuinely at a coolant temp of around 70C, you can trick the cts into any lower value and it will start.
If it is genuinely at a coolant temp of BELOW about mid 60's C and ABOVE about 15C, then it will not start without major cranking WHATEVER temp you set it to apart from Below about 15C.
If it is at Normal temp (around 70C) - you can - as said - set the coolant temp 'fooler' to anything at all apart from going to around 100C or above where again it refuses to start.
This is all completely repeatable.
That is why it would appear to be a definite issue with electronically controlled fuel delivery on cranking only ( which can only be laid at the door of the ECU which controls injector opening times). Absolutely no evidence has been found of any mechanical fuel system issues / pressures. The reason I say cranking only is that once started the engine runs perfectly well.
These things are sent to try us lol

It has been an interesting exercise and quite thought provoking. Has also woken the old grey matter up in a few areas.

Joe

Joe_H said:

Interesting Nodge, Yes, On closer examination of the pump there appears to be a HP one way valve arrangement on each of the three plungers (the delivery ball valve)
Also an inlet (fuel suction valve) which acts as a one way path from LP to HP on the suction stroke. This arrangement would allow LP through to the HP when the pressures had equalised as the HP residual reduced. The suction valves would effectively be 'floating'. No HP could return though due to the delivery ball valve.
I am quite amazed that you got 10 mL in a minute on the LP pump only ! - Have you ever seen a spec for that system ? - On other common rails I have worked on a figure of around 10ml per minute at idle. certainly NOT on LP. - Have you any documentation that satisfies you that the leakoff on LP only on that system is normal - (Isn't the pump a CP1 or derivative ?)
Thanks for the info nodge
Joe

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I don't know the figures for the TD4 leak back volume. However when my wife accidentally filled her 2013 Astra GTC with petrol, I was able to drain the tank completely, simply by letting the LP pump, pump the fuel out the injector spill rail. It happily spilled a litre a minute from it's injectors. This was with the engine stopped, as it wouldn't run on petrol.

Yes It is starting to look like devising a dash switch is the way to go with this. Its not that random though as I consistently know it wont start unless ecu administers a cold start or unless engine is already very hot. Any switch designs and dash positioning very welcome

REDNAL3 said:

Yes It is starting to look like devising a dash switch is the way to go with this. Its not that random though as I consistently know it wont start unless ecu administers a cold start or unless engine is already very hot. Any switch designs and dash positioning very welcome

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I believe it has been proven NOT to be random at all, it is fully repeatable as all the tests show.

Regarding the switch -

Joe_H said:

just cut the slate / blue wire (white and blue) - extend them into the cockpit and attach to a small switch.
Switch open - start - switch closed - run

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Literally that ! , the leads going to the plug, cut the White/Blue wire (It is actually slate grey / blue) and attach the two now exposed ends (solder and seal) to a length of twin core cable - or obviously two single lengths of cable - long enough to reach the cockpit. At the end of these two wires put a switch.
Switch OFF (OPEN) for start, Closed for RUN. open removes cts from ecu, closed connects cts to ecu.
Simple - put switch wherever is convenient and wont leave an unsightly hole in the dash..
You could use a push button instead - a push to open unit - and press whilst you turn the key. You can also get a spring loaded lever switch, like a normal switch that doesn't lock, you have to hold it in position and then when releases it automatically closes the circuit again.
Joe

Not sure if any relevance to previous issues but I was looking for a route through the bulkhead to cab to run the switch wire and found this small box sited in wall of driver footwell . Any idea what it is? There is also an uncoupled connector plug nearby and cannot find anything in the area that it could possibly go on to. .There is also a black wire that comes direct from battery to fusebox (pic 2) . Are any of these Possibly to do with tow bar ?

Rather than run a wire into the car. Why not connect a changeover relay, NC terminals to the coolant sensor wiring, instead of a switch. Hook the coil of the relay to the starter trigger terminal and ground. That way when you turn the key to start, the relay will disconnect the CTS, but reconnect it when the key is released. That way it's fully automatic with no driver intervention

I am really really liking the sound of this This may be the automation plan Joe had alluded to in an earlier post. Is there a link, another post or a diagram I can follow to do this ?

Hmm, you need to find out what that crap box is and remove it......

Hello
It's a split charge relay for the towing electrics. Charges the leisure battery, but stops it discharging the car battery.
What the fook it's doing there is anyone's guess. Should be in the rear quarter panel.
Still working on the grey plug, but it might be to do with the old towing relay.
Mike

Have you ever tried the towing electrics?
Mike

No I havent tried them I don't have a trailer. I have a friend who has one though. Can I test with multimeter ?

It's so much easier to plug it into a trailer. I don't believe they'll work. I'm coming to the conclusion that the previous owner fried the relay and put that one in so they could still charge an auxiliary battery.
Could be wrong, but plug it in and see what happens. Either way I'd be inclined to disconnect that botch job.
Mike

It might even be worth looking at the rear lights to see if they have extra wires coming out. That's an old way to botch bad towing electrics.
Mike

Nodge68 said:

Rather than run a wire into the car. Why not connect a changeover relay, NC terminals to the coolant sensor wiring, instead of a switch. Hook the coil of the relay to the starter trigger terminal and ground. That way when you turn the key to start, the relay will disconnect the CTS, but reconnect it when the key is released. That way it's fully automatic with no driver intervention

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Can anyone send me an idiots guide on how to go about this ?

Nodge68 said:

Rather than run a wire into the car. Why not connect a changeover relay, NC terminals to the coolant sensor wiring, instead of a switch. Hook the coil of the relay to the starter trigger terminal and ground. That way when you turn the key to start, the relay will disconnect the CTS, but reconnect it when the key is released. That way it's fully automatic with no driver intervention

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Hi Nodge can you or anyone possibly help me with a rough diagram on how to carry this out ?

REDNAL3 said:

Hi Nodge can you or anyone possibly help me with a rough diagram on how to carry this out ?

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Yes it's easy to do.
You need a 5 pin relay but you'll only need to use 4 pins of it. These are numbered 30 85 86 87a. The 87 pin won't be connected.
Pin 30 and 87a need to be connected to one of the coolant sensor wires. The wire needs cutting and joining to these two pins.
The 85 pin goes to a ground connection.
Pin 86 needs to be joined into the starter trigger wire (thin wire)
This will then disconnect the the coolant sensor when the engine is cranking but reconnect it when the starter is released.
You can Google 5 pin relay for an idea of what it is.