C4 Coupe (_LA) Can’t start after failure

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C4 Coupe (_LA) Can’t start after failure

Post by Modami »

Hello there everyone,
Super short description of problem - my wife’s car just died and it’s not firing up. I’m looking everywhere I can for some clues/tips or similarities - to fix it in case of workshop failure.

The patient is 2005, Citroen C4 Coupe (_LA) 1.6 16v (80kW/109hp) TU5JP4 if I remember correctly, equipped with Bosh ECU. Current mileage 209,5k.

What happened - I started the engine without any problems, I left it on for ~2m to let engine spread the oil. We were on the highway, going to the shop.
Suddenly this appeared “Anti Pollution System Failure” with blinking Engine Management light. Whole car started to shake. It lost whole power, but we managed to drive it 70km/h. Perfect day for malfunction - Saturday. One of workshops was still open. They connected it to Wurth and then to Lexia (I guess).

Car was still able to drive and start at this point. They’ve found vent error, but this is my fault (cheap replacement used), clutch sensor (it doesn’t have clutch sensor) and a list of codes P1336, P0351, P0352, P0353, P0354. They didn’t even checked the car - just removed all the error codes. On monday they called me to pick it up, “we are not able to fix it/we don’t know what is wrong”.

At this point - whole situation got worse.
It is spinning but it’s not able to fire up.
They said engine timing is bad. (XD)

The same day I managed to get in touch with guy focused on french cars.
It took him one day to check whole car - he couldn’t say a bad word about parts/electric system in general.
What he checked:
Engine Timing, battery, starter, dynamo, sparks, coils, cables, fuel pump pressure, fuel filter, engine fuse box/cab fuse box, lambdas, oxygen sensor, groundings, camshaft/crankshaft sensors, engine compression, injectors, actuator. At 160k we fixed full set of gasket, engine timing, water pump, sparks.

However, he noticed some strange behaviour during startup attempts - lights/indicators automatically turned on as well as wipers. In addition - irregular ignition - whatever it means.
His final conclusion = major ECU failure but he is not 100% sure. There is no SERVICE or STOP light on. No further error codes - because it cant start I guess.

Patient have some ongoing problems like:
ESP/ASR System Faulty - this one is tricky and I cant figure out what is causing it -.- The system itself works, when error comes up - it doesn’t,
Vent working on one gear - broken resistant,
Smell of petrol inside cabin - when tank is at 50% or lower and when AC is on regardless of tank level,
Limiter works but cruise control doesn’t - when I try to use CC there’s an error on display and noticeable loss of power,
Sometimes it just can’t fire up - randomly. It can’t even spin. Starter was replaced, battery also - no, no strange noises coming from engine.

Just in case here is the VIN: VF7**************[VIN obfuscated, can be read by forum staff]

I would be grateful for any help and clues what the hell happened to it. Maybe there is some small thing I should check.
Thanks in advance