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Obviously you have diagnostic equipment.
Charge voltage through diagnostic equipment is a little low but OK.
Have you looked at live data and selected engine rpm whilst cranking? That checks the crank sensor.

How old are spark plugs?
Look at live data- things like spark advance to check that the system is trying to start it. Ditto check "starting authorisation" in live data for the same reason.

It could be you have an ignition switch issue but be guided by the results to these questions.

Sometimes the spark testers which fit on end of spark plugs are a great way to see if the coils are firing. It can save much checking of other stuff.
 

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Starting authorisation is just the OK via the immobiliser.
The ignition advance is just a way of checking that the module outputs are functioning.

Don't keep the plugs in for 100k km if you don't like changing coils. On that score, I suspect marketing people put pressure on engineers to schedule plug changes at 100k. They always look in poor shape by then. Even worse, the BKR6EKPA plugs are an alternative to the PFR6B plugs which I find superior. They are the type used in 24v Busso engines.
 

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That is really all that is needed to test spark plugs. The engine can run with these on for test purposes. The brighter the flash, the more energy is needed to make the plug spark which means worn plugs. No flash may indicate the coil cannot provide enough energy.

I'm not sure why your system does not display the spark advance. It should be around 6 degrees at idle and is a little more than a Twinspark engine uses (for obvious reasons).

The drop-out in engine rpm, especially on graph 2 is harder to answer (time count around 10-183). What would be really helpful is to see if you can get a graph or just check the live data when it won't start. When running, it seems OK apart from the rpm signal drop out but if the ECM saw that, it may record it as a fault code but not necessarily so. It depends on conditions. AFAIK, it is more likely to record an rpm fault code if the engine was running at speed, say 3000rpm and then nothing.

High pressure fuel pump delivering 50 bar pressure at idle seems good. That is what my JTS does.
 

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To check for current leak, it needs a multimeter connected in series to one of the battery leads. The trouble is door latches must all be in the closed position (even though some doors are open), same with bonnet. Then when all is switched off, after about 2 minutes, then disconnect the battery lead from the battery terminal so that all the current goes through the meter. Then you can look at the current draw. Even with alarm on, it should be not more than 0.03 amps, possibly half that.
Care must be taken though as any power left on may drawn too much current and blow a fuse in the meter. Ideally a inductive tester would be used to measure residual current drain.

I'd have the battery tested with an electronic analyser first though.
 

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As you have been able to measure battery current draw (door latches set to closed manually but doors open), the way to trace the current draw fault is to pull fuses one by one and see which one makes the biggest difference. Before doing that, is there any non standard car hi-fi. Has it been wired to a permanent supply rather than through the ignition?
 

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To recap, does your management system display data for injection time and spark advance whilst cranking?
If not, what is displayed for engine startup and key position when ignition is on (MAR)?
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If you are measuring residual current draw, the car must be in exactly the same condition as it is normally left. As I stated before, the door latches, bonnet and boot must all be set to closed even though the doors are open. If the alarm is set, set it on. Then wait 2 minutes before making any measurements. The the current draw is then more than 0.02 amps, start disconnecting the fuses one by one to see which circuit the current draw is in.
If it is higher than I stated, list which circuit makes the biggest difference and by how many amps.
I should have stated, because your car is Selespeed, don't attempt to measure current drawn within at least 2 minutes of opening doors or having the ignition switched on. I'm not sure how much current the pump will draw and I don't wish any damage caused to your multimeter.

I don't see any point trying a different key. What does the status of engine startup state?
What does MES state battery voltage is when ignition is on?
Do you have a multimeter to measure battery voltage? If so, what is it (ignition on)?
How old are the spark plugs? Are they in good condition?

Hopefully you will have the spark plug testers soon to confirm if spark plugs fire. I realise the plugs are down a well but there should be sufficient darkness to see them. I find they work on TS and JTS. If everything is in good order, the spark should be quite weak. If the spark plugs are worn, the spark must jump a larger gap so the spark is stronger.
 

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I only properly read your last post after my last 2 posts. Sorry. You can use these posts for information but I'd check spark plugs anyway. For information sake, I prefer the PFR6B plugs to the BKR6EKPA plugs. They are cheaper and the BKR6EKPA were only offered as an alternative anyway. I'll disconnect my coils and see what my battery voltage during cranking is and report back.
 

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Key status at MAR is correct.
Battery seems OK but I'm not so sure right now.
Load test on battery suggests it isn't so bad.
Residual current draw test suggests car is OK.

I'm not sure what starter motor the JTS has but after finding 2 listing, I expect the high compression engine should have the 1.4kW one and the 1.1kW one is for the TS.
That suggests the starter should draw 130amps and another few amps for other electrics. Say 150amps total.

You could measure engine cranking speed with MES. Ditto battery voltage. It may be best to graph them simultaneously. I'd expect 11+ volts and 300+ rpm.

I don't expect spark plugs to be bad at 50k km. New will still be better though. I'm guessing car has been in regular use recently and there have been no changes to your fuel buying habits.

I tried getting data but ran out of time due to a couple of issues. I still have a question about the battery though because 12.3 volts equates to around only 20% charged. That would mean a lot of power needs to be drawn overnight yet there is as yet no sign of a significant parasitic drain.
 

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Check battery terminal voltage.
Check battery voltage with earth onto body.
Check battery voltage with earth to engine.
Check voltage through diagnostic plug.

Any discrepancies point to a high resistance in the relevant earth points or through the positive supply.
I'd also check voltage at and through the ignition switch.
 

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The latency too high warning can still occur even when latency setting in laptop is reduced to minimum. I don't put much weight behind that.

Voltage and cranking speed seems OK.
The spark advance data is a way to ensure the spark is occurring when it should. I do not know why your system does not display it. Linked to that I kind of question the cam sensor. That would ensure the spark happens on compression/ignition rather than exhaust/induction. You don't have a cam sensor fault code though because you'd have mentioned that.

That goes back to everything looks fine but it doesn't start. That's why I'd like the spark testers to verify if plugs are sparking.

So far we are left with what we can see is seemingly OK but still the car sometimes won't start. I think I'd start looking more at the ignition switch. It may be that certain module functions can operate without ignition being switched to MAR but that statement seems wrong if the starting authorisation is OK. No doubt this is an elusive problem but it may be worth simply swapping the main ECM relay to rule that out.
 

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I don't think it is time of an auto sparky.

The cam sensor is mounted at the exhaust cam pulley around the 8 o'clock position. The wiring connector is mounted on top of the inlet manifold, I think. I'm sure the housing is blue. Hope I'm not getting confused with a TS though. I don't think that is the issue as a fault code should readily appear.

Big clue is petrol. I think your fuel may have gone off and lost volatility. I'd drain a bit from the low pressure connector at the inlet manifold. Put a thimble or half an egg cup of the stuff in a container (not combustible) or even concrete and light it. It should instantaneously cause the whole lot to burn. If you can see the flame travel, it is just not volatile enough. That's why I say the ground. Ideally concrete with low porosity.
 

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There is a similar thread but with a JTD. The last advice on that was to try a crank sensor. I'm not going to argue with experience. I thought that if it shows a plausible engine speed and spark advance whilst cranking, that should mean both good inputs and outputs. It may not be the case though and no matter how unlikely I think it may be a crank sensor, I think the cost of one is worth it for the time and a trip to a sparky.

If you have an oscilloscope, by all means, have a close look at the wave form whilst cranking on starter. Typically if an indictive pulse sensor is starting to break down, there is a pause and a lull in the rising sine wave form before it suddenly overcomes a high resistance and then largely follows the form it should produce. Because the amplitude is proportional to engine speed, is is possible a glitch in the signal during cranking can cause issues.

I don't like suggesting 'try a part' but it's going that way. There are bits where I am not sure whether the supplied results were whilst cranking or engine running.
 

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Sorry, I must have forgotten that the crank sensor was changed.
I struggle when things done are not simply listed.

To get exactly what is going on, the car starts 2nd try?
It cranks fine.

Have you simply tried turning the ignition on (MAR) for 2-3 seconds to prime the low pressure fuel system? Possibly do that twice before trying to start. Result?

Have you diagnostically measured fuel pressure in the high pressure fuel rail before trying to start it? An initial graph of fuel pressure may be useful taken at the point of first cranking.

You stated it starts 2nd try. How long do you let it crank 1st try? How long does it crank 2nd try before starting?
 

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I have another couple of ideas.
Firstly, look at the cylinder compression pressures. (Hopefully you can get a tool to test). I'd like to know if there is a significant difference between first thing in the morning and with a fully warm engine.

Another thing to look at is the fuel trims. Look at this thread for reasonable details;
 

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Yes. I don't know what data there may be for short term fuel trims given that the O2 sensors will be offline. It's at this point I wish there was more information about the map and adaptive learning.

I did wonder about the valves. What distance has your JTS covered? That can only be a guide though as conditions and quality of fuel make more difference. Couple to that I read on BITOG that modern oil which is made more viscous with VII tends to be responsible for stuck piston rings and sticky deposits to the point that people seem to get good results going back to a 15w/40 or 20w/50 to free the rings. It makes @johnlear 's choice of Pennrite 15w/60 look very intelligent.
 

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OK. Nothing badly wrong there but a couple of things are a little unusual but I must remember you are in summer heat so probably mid-high twenty odd degrees.

The air temp is fairly high but somewhat expected due to heat soak.
MAF is rather low. It is lower than I've seen a 1.6TS at idle.
LTFT are leaning the mixture a little.

Your car has covered a fair distance and I'm guessing the engine hasn't been apart. I'm guessing you have the JTS hum of restricted airflow by 5000rpm. Maybe earlier?

At this point I'd definitely like to know what compression pressures are- especially when engine is cold.

If you like, you could try to get a maximum MAF sensor reading but it may need an assistant and I don't think your engine would sound nice at 6500rpm with a wide open throttle. It will probably sound like it is in its death throes.

With all the information so far, I think a temporary loss of compression is what you are experiencing. It is not unusual for direct injection engines to experience this.
Not a definite though. Just an idea.
 
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