Xsara Picasso won't start

[Vuk1987]

I´m beginning to think that my ECU is dying. Too many wrong things at once.

[Vuk1987]

I now believe that it's a temp sensor connector-wire issue. When I reach it, refit it, car works fine, but when I put everything back together (air intake-which is in the way) the problem is back. I will check connectors on both ends and check the wires. But i really need daylight for that. So, Saturday maybe.

[wheeler]

Did you remove the ECU plugs & check for water/coolant?

[Vuk1987]

I wanted to, but couldn't find ecu
I searched for it around under bonnet fusebox, but without luck. Can someone tell me where is it?

[wheeler]

This one is a diesel but the ECU is in the same place. Its should have a ‘shower cap’ over the 3 plugs to help prevent water ingress.

[Vuk1987]

OK, I have the exact same "bag", I just taught it's a cable insulation.

[Vuk1987]

I checked the top 3 connectors, and there was no water. I just wonder, even if I have found it, how should I clean it? Other than disassembling it. I'm getting fuel pressure manometer I belive in Tuesday in order to check the fuel pump pressure. I'm thinking about learning and repin all the ecu connectors

[MixerFistit]

I'm not familiar with these engines nor can I offer much direct advice, but having read through the entire thread, I will say in last few posts, you appear to be in danger of going down the dark path of confirmation bias.
You've latched on to the ECU as a problem.
Indeed it could be, but before you go in too deep with that, step back, count to 30, go back to the beginning, and check all of the other stuff. Breaks in wires, dodgy sensors, split hoses/pipes etc etc.
I've been down that path too many times for my liking and try my best to steer clear these days.

[Vuk1987]

MixerFistit that is a good advice.

I'm all about fuel line now.
Here is my measurement of fuel pressure:


Now

1) Fuel pump was original problem, the previous died.

2) Mechanic replaced it with a used one on his initiative because he told me that new ones come without one direction valve and I would have difficulty starting the car.

3) It is clear that this one doesn't have a one direction valve (check valve is English word, I think, if I'm wrong sorry, I'm gonna call it that way in this post).

Now:

Is pressure indicated on video sufficient?
If not, I guess I should just replace the pump.
Should there be one direction valve any ware on the line?
In that case, should i just put one in?
Could there be a problem with part of electronic responsible for fuel pump operation?
I have an lpg installed, and I believe there is a relay switching the pump off when car runs on lpg, or maybe not, maybe it just bypasses a petrol line, I don't know.

Maybe toping up the petrol tank could fix the problem?

I couldn't run the car with fuel pressure gauge on because when I tried to mount it instead of fuel filter it leaked a lot and then I went straight for the pump connection, but didn't want to flood my cabin with gasoline. It would take months to get the stench out.

Guys, I'm over a month in this problem.

Oh, and, when I manage to start the car, after it heats a little it works fine in lpg.
When he's warmed up, mostly it won't star on gasoline, but starts just fine when I manually switch it to lpg.

[CitroJim]

I can't be sure in your case but most in my experience - admittedly older vehicles - seem to run around 2.5 to 3 bars fuel pressure so that to me, looks very low and likely too low.

[Vuk1987]

Long story short: it was fuel pump. Replaces today myself, car works just fine.

Long story medium long: The fuel pump was original problem, but mechanic managed to play with my head and convince me that it isn't. I know I had similar problems last year due to temp sensor malfunctioning. In some conditions when I unplugged the temp sensor, engine run fine. All those ecu fault codes confused me, mentioning injector circuits (as in, if it's a circuit, it must be wire related).

It was fuel pump all along.

Case closed.

Thank you all people for the advices.

[CitroJim]

Excellent and delighted to learn of the successful resolution