It's a technical impossibility for air to come out through the FPR's hole, the hole is above the diaphragm, it's nothing there just a spring, on other makes which are using that kind of FPR that hole is the vacuum port which can fine tune the fuel pressure , i can't find a scheme for td5 but the general principle is like in the pic, if there was a hole in the diaphragm fuel would escape there not air

automotive-fuel-and-emissions-control-systems-22-638.jpg
 
I’ve no idea then. If you’ve seen that video you’ll see it is what seems like air coming out. That’s a new FPR
 
Where is vacuum applied to a TD5 FPR?
Read again my post, i said on other makes... and the principle for the td5 is like in the left image with no vacuum applied
I’ve no idea then. If you’ve seen that video you’ll see it is what seems like air coming out. That’s a new FPR
in the first video which i said it's normal that hissing might be the sound of the fuel passing beneath the diaphragm with high pressure as the injectors are closed it's all recirculated and then it can be above 5 bar, on the second video i dont know what's going on cos it seems that the engine is mechanically throttled
 
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I went out and checked cos i was intrigued, no, i can't feel anything at the FPR's hole, it would have been a great surprise to me to feel, as i presumed that it's the fuel's sound through the FPR or pipes at high pressure i listened at the filter too and as my pump is very silent i can hear a hissing sound there too together with the pump's silent buzzing noise.... no matter which way i turn this it seems impossible for me to comprehend how air could come out there, what ever happens only fuel can come out there IMO
 
I can't feel it with the engine running. I very much doubt this is a fuel supply issue though, just clutching at straws!

If the copper washers for the injectors had been "going" for some time, what would the effect of that be? I am thinking perhaps one or more has been loose in the injector socket, no idea if this could cause damage to the socket itself??
 
make somehow an save another data log from the cold start which contains the symptom and post it here, untill then do a simple thing, unplug the glow plugs and measure each's resistance across the terminal and the head and tell me the values
 
in addition to the above, to rule out all the possibilities as this issue is really odd, ask somebody to start the engine from cold and measure the battery voltage while the symptom occurs to rule out a voltage drop at that particular moment cos if let's say the alternator has a delay in it's excitation on the initial start and it's not charging while the battery lost from power on cranking if the voltage drops below 10V the ECU can't manage the injectors well... off course just grasping at straws with this one too
 
make somehow an save another data log from the cold start which contains the symptom and post it here, untill then do a simple thing, unplug the glow plugs and measure each's resistance across the terminal and the head and tell me the values

Unfortunately the Nanocom is unable to record a startup, as it resets as soon as the engine is started! I can do it with Lynx but it limits the data recorded to about 6 items.


in addition to the above, to rule out all the possibilities as this issue is really odd, ask somebody to start the engine from cold and measure the battery voltage while the symptom occurs to rule out a voltage drop at that particular moment cos if let's say the alternator has a delay in it's excitation on the initial start and it's not charging while the battery lost from power on cranking if the voltage drops below 10V the ECU can't manage the injectors well... off course just grasping at straws with this one too

We do know the alternator is only putting out 11-13v, but I will check anyway. I was reluctant to change it with the prospect of the head coming off anyway.
 
We do know the alternator is only putting out 11-13v, but I will check anyway.
That's not good cos if the rectifier is fubar this will also induce a quiescent current draw .... would be a real surprise to realise that it was an electrical issue all the time o_O
 
I have said this my mate but as he keeps saying, an electrical problem can't drawn air in
 

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