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Rootriver

1.8 TDCi not starting when hot (QYBA engine)

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Hello All,

I have a 2008 mondeo with 1.8 Tdci (QYBA/Lynx). Apparently Mk2 Focus can have the same motor, so I also posted here, as there has been no help else where. 

First my EGR gave fault code P141A and then the car started to refuse igniting when motor was hot few weeks after that.

I blanked the EGR with a steel plate, and the problem got little better (ignites better as the air is purer?), but still refuses to ignite every time. The engine kind of ignites, but then stalls. I had the plugs replaced 2 years ago. OBD shows that rpm is pretty much same hot or cold as is fuel rail pressure when trying to ignite. (400 rpm and 35 MPa, hot even as high as 50 MPa). I also tried to see if any temp sensors go wild/numb when hot. The catalytic sensors showed temp 0°C and 1 of them showed -40°C, but I wonder if the car even has them? Other sensors seemed to give believable values.

Ignites like a charm every morning and after work, but I cannot go to grocery store, as the car won't neccessarily start afterwards. The car will also start nicely when towed or rolling down-hill (its manual). Car also runs fine when hot, once I get it running. Sometimes it ignites properly after 3-4 staring attempts. 2 times I got it to raise to 900-1000 RPM (idle) when actually hot (cylinder head temp around 90°C), but the engine stalled anyway.

I replaced the injectors (inspired by this thread https://www.fordownersclub.com/forums/topic/85292-mk6-14-tdci-wont-start-when-warm/?tab=comments#comment-736250 and youtube videos). Now I am thinking it might be anti-shudder valve if the engine has one? (https://fordtransit.org/forum/viewtopic.php?f=54&t=167029&c=1#p1423392, about not having it: https://www.fordownersclub.com/forums/topic/108392-throttle-position-sensor/?tab=comments#comment-768387) I assume that this is the "kill-switch" that cuts off the fuel supply to turn off the engine?

Any ideas? Is it the EGR that is maybe fooling ECU some how? Fuel pump (either high pressure or extraction pump in the tank)?

These are also the "hardest" modifications I've ever done to a car, so please be patient if I am asking stupid questions.

Thanks for your help!

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