Flashing EML. With ProBoost

Erm, i did change the belt and pump recently!!! 99% sure it was aligned properly though....

Dayum!!!
 
If the timing is out, you should get a DTC, can't recall the exact description at the moment, but it's that the crank sensor is out of correlation with the the cam sensor. The ECU knows where the camshaft should be, relative to the crankshaft.
Found it:
"P0016, Bank 1: Camshaft Position Sensor (G40) / Engine Speed Sensor (G28): Incorrect Correlation"
So, if that DTC is absent, timing is, probably not the problem.
Just a possibility, if you use higher octane fuel, V Power 99, the ECU will trigger the spark later, than on 97, or, it would on a standard ECU. Since ProBoost was as much about about using 95 octane, as about the flaps, (until E10), it's quite possible that it has the timing permanently advanced, so that the high compression engine can run on lower octane, without knocking.
In the short term, I'd try half a tank of 95 E10, "essence ordinaire"

As I've said before, we don't know enough about Pro Boost.
Do all ProBoosters use E5? I wonder ...
Mac.
 
The EML flashing, rather than coming on, and staying on, is because the trigger for the EML is a transitory condition, misfire, or knocking.
The DTC is logged, but EML clears, when the condition clears.
The "condition" seems to be related to the octane rating of the fuel.
Higher octane fuel, typically, allows the timing to be retarded, with the spark occurring closer to TDC.
In retarding the ignition, comes the risk of the fuel self combusting before the spark, pre-ignition by compression ignition. This is a possibility here, I think.
When were the plugs last changed, and are they the correct triple quad electrode type, (NGK preferably)?
Mac.
Edit: Could also be bad fuel has fouled the plugs.
 
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Are the correct NGK plugs 408441140? They are 4 earth prongs, not 3
You are indeed correct, four electrodes. NGK plug finder shows ZFR6S-Q.
That's what I have in mine.
Mac.
Screenshot_20250116-143233.png
 
Update. Again.
Fitted the NGK plugs yesterday, and noticed an improvement straight away. The ones in there were Denso 3 electrode ones, and I'm pretty sure I didn't fit them. I know I have cleaned them in the past. They were just a bit black and dirty.
When I'm home, I am going to take it for a decent test drive.

I will report back in due course.

On an unrelated, I mentioned a while back that occasionally I get the big red oil sign light up, even though I have decent, and enough oil in the engine. I thought it was the oil level sensor.
Its not, it's the pressure sensor. And it's leaking. From the middle of the sensor, not the fitting thread.
In all my years of driving, I've never seen that before.
 
Happened to mine, leaked from centre. Easy fix which I'm sure you know.

Watch not to over torque it, threads are not great.

I hope it was the spark plugs! Gratz on the fix if so.
 
Exactly 100% the same symptoms as me (@PlasticMac knows ALL about my issues) - I just replaced the fuel filter and it hasn't happened since, however I have yet to make a longer journey which is usually what brings it on (i.e hot engine more than 30 minutes continuous drive). My ProBoost arrived today, so reading your tale I am now extremely dubious it will sort me out 🙄
 
Exactly 100% the same symptoms as me (@PlasticMac knows ALL about my issues) - I just replaced the fuel filter and it hasn't happened since, however I have yet to make a longer journey which is usually what brings it on (i.e hot engine more than 30 minutes continuous drive). My ProBoost arrived today, so reading your tale I am now extremely dubious it will sort me out 🙄
What plugs are you running Simon?
Mac
 
The EML flashing, rather than coming on, and staying on, is because the trigger for the EML is a transitory condition, misfire, or knocking.
The DTC is logged, but EML clears, when the condition clears.
The "condition" seems to be related to the octane rating of the fuel.
Higher octane fuel, typically, allows the timing to be retarded, with the spark occurring closer to TDC.
In retarding the ignition, comes the risk of the fuel self combusting before the spark, pre-ignition by compression ignition. This is a possibility here, I think.
When were the plugs last changed, and are they the correct triple quad electrode type, (NGK preferably)?
Mac.
Edit: Could also be bad fuel has fouled the plugs.
If I may, higher octane generally allows to use more timing advance, not less (as the lower self ignition characteristics of high octane fuel will make for a controlled combustion rather than disorganized detonation even if sparked earlier in the cycle when the piston is still compressing)
 
On an unrelated, I mentioned a while back that occasionally I get the big red oil sign light up, even though I have decent, and enough oil in the engine. I thought it was the oil level sensor.
Its not, it's the pressure sensor. And it's leaking. From the middle of the sensor, not the fitting thread.
In all my years of driving, I've never seen that before.
Had similar, although it was only leaking under load.
 
If I may, higher octane generally allows to use more timing advance, not less (as the lower self ignition characteristics of high octane fuel will make for a controlled combustion rather than disorganized detonation even if sparked earlier in the cycle when the piston is still compressing)
I thought retarding the ignition means delaying the spark, so it occurs closer to TDC on the compression stroke, which using higher octane fuel allows.
Advancing the ignition means the spark occurs earlier in the compression stroke, allowing use of lower octane fuel.
Have I got my retard and advance the wrong way around? Sorry if so.
Mac.
 
I thought retarding the ignition means delaying the spark, so it occurs closer to TDC on the compression stroke, which using higher octane fuel allows.
Advancing the ignition means the spark occurs earlier in the compression stroke, allowing use of lower octane fuel.
Have I got my retard and advance the wrong way around? Sorry if so.
Mac.
Retarding is indeed as you describe: bringing the spark closer to TDC (i.e. less advanced with respect to TDC), but it is the conditions for doing so that we differ on (and regarding which I respectfully stand by my argument)... for example some engine ECU would take out some advance when experiencing detonation (say using fuel with less octane). The confusing thing may come from the different causes of detonation (e.g. hot spot within the chamber), but if I understand this correctly retarding when using lower octane has the purpose of avoiding faster than normal combustion too early in the cycle (more octane makes for a more consistant, controlled combustion, with a same flame front speed over the whole range of RPM, and as a by product allows for more advance for optimal tuning).
 
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Higher octane means a slower and more predictable burn, so you can “advance” the timing by firing the plugs earlier, further from TDC.
 
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