2016 Relay 2.0 BlueHdi - Smokey!

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2016 Relay 2.0 BlueHdi - Smokey!

Post by Paulus1983 »

Hi All,

A bit of a story to this one. I have a 2016 Citroen Relay 2.0 BlueHdi and its smoking...badly! This is currently running a remap which was done before my time. The van runs and starts fine but the black smoke is very excessive. Just to point out that the smoke is a new fault and the van had been running fine for some time prior to this. So, my thoughts on this originally was an injector issue as I'd had a few low fuel rail pressure fault codes, along with a P1163 code. I had the van at a local Citroen garage who told me they couldn't communicate with the engine management system ecu, which controls the injection system. The question I need answering is, if this ecu loses comms or is corrupt in some way, would that affect the fuelling/injection system also and maybe that is whats causing the smoke. Maybe overfuelling because the ecu can't control the spray pattern or amount of fuel required. The smoke only happens once the van is up to temperature, which would also point to overfuelling in my opinion. Would the next best step be to replace the engine management ecu, re-code the injectors and see how it goes from there? I do have a spare set of injectors for the van but I'm holding off changing these as I've read the horror stories of people carrying out that job.

Any help or advice would be greatly appreciated.


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Re: 2016 Relay 2.0 BlueHdi - Smokey!

Post by GiveMeABreak »

Another re-map fail it looks like.

Yes correct, if the engine ECU is re-mapped it can overwrite the programmed parameters specifically designed for the vehicle and cause issues. If Citroen cannot now read the ECU, there is nothing they can do. My initial response would be for them to re-download and configure the engine ECU software from their servers, but if there is no communication with the ECU itself, then this won't be possible. This leads me to believe that something internal to the ECU has happened and caused a failure that has also lead to your air and fuelling problems.

This is likely going to need sending off for repair or replacement and recoding. Of course, it goes without saying that you will no doubt be getting further faults and whilst this is happening it can well put strain and wear on the other components, as long as an MOT fail as there should be no smoke on a Blue HDi. So I wouldn't leave it if I were you.