new owner of a 2008 c5 sallon

[Ardtullaich]

well i have had my c5 a moth now and i have found several issues.
i love the car and its very comfortable ride even with it being coil sprung.
first problam i have is fault code reading fuel pressure sensor and the fault that shows up on the screen in the car is depollution fault. Comes in about 2500rpm then it will go off after a couple of days then come back on i bought a replacement sensor of ebay same part number but the car wouldn't even start until i replaced my old one. Last week i had the car remapped and removed the dpf and egr valve thinking this would cure it but the fault is still there.
second noticed car never really gets hot only 1/3 on the gauge reading only to discovery a connection unplugged at the fan and when i reconnect it the cooling fan runs constantly until about 10 seconds after turning the ignition off and it restarts as soon as i turn the ignition back on so i left it disconnected the car has never over heated.
And the cruise control also works intermittently some times i can use it on the motorway and then when i enable it after using the brakes for instance to slow down i just l have dashes on the display when i stop and restart my journey the cruise control is back.
Can any one help with my issues? or even recommend a good work shop manual with all wiring diagrams.
ironically my cousin is a citroen mechanic for the last 25 years for a main dealer but he lives 350 miles away .

[GiveMeABreak]

This Forum doesn’t condone removing or disabling any emissions equipment as it is illegal for road use. Please read the Acceptable Usage Policy that you agreed to when joining.

You are likely to get errors as you have removed these devices, and we would encourage you get them reinstated.

Not least because you will not be covered by your insurance now as a result, regardless if you have managed to pass the new MOT.

It is very likely, that all your problems could be resolved through regenerating the particle filter or cleaning the EGR valve or topping up the additive system. Without these devices present it’s very likely you’re going to continue to get errors and problems and fault codes which is really beyond the scope of any help here because of your actions.

Apart from your emissions faults, please create a new post for other individual faults like the cooling system if you cannot already find the answers by searching.