Greetings to everyone!
Last time I wrote about all the new parts we have been making. This time I want to talk about a problem instead — one that has been following our blueHDI kits around for years, and which is now finally solved.
The problem
If you have fitted an aftermarket intake to a Peugeot or Citroen blueHDI, you probably know exactly what I mean. The car drives perfectly, pulls as it should, and then the check engine light comes on and stays on.
The code is usually P00BC — mass air flow sensor A circuit range/performance — or something very close to it.
Here is the frustrating part: the car is fine. There is no limp mode, no loss of power, no fuel consumption penalty. Nothing actually stops working. The light simply sits there permanently, and it will not clear by itself. The only way to get rid of it is an engine parameter calibration adaptation reset with diagnostic equipment.
And this affected all blueHDI versions, not just some of them. Other cars we make kits for have ECUs that adapt to a new intake within a few driving cycles and get on with life. The blueHDI ECU does not. It makes up its mind and stays there.
Why it happened
The mass air flow sensor on these engines is unusually particular about how air arrives at it. In the original airbox it sits in one very specific flow profile, and the ECU expects readings inside a narrow window based on that. Move the sensor into a different housing and the readings shift — not enough to affect how the engine runs, but enough for the ECU to decide something is out of range and log the fault.
So this was never really a fault at all. It was the ECU disagreeing with the geometry.
The solution
We have redesigned the MAF adapter.
The new adapter puts the sensor back into the flow conditions it expects, and the result is exactly what it should be: the kit no longer triggers the check engine light at all. No code, no reset, no trip to a diagnostic specialist afterwards.
Every blueHDI induction kit we ship now includes the updated adapter as standard. If you are fitting one to a blueHDI, there is nothing extra you need to do and nothing extra to buy.
If you already have one of our earlier kits and have been living with the light, get in touch and we will sort it out.
The installation video
While we are on the subject, the full blueHDI installation is now on video. If you prefer watching to reading, this covers the whole job from start to finish:
Watch the blueHDI intake installation guide on YouTube
The written step-by-step guide is still there too, and some people prefer it when they have the car in pieces and oily hands: Peugeot Citroen 1.4L 1.6L blueHDI intake installation.
Remember that the heater element connection differs depending on your car: the colder climate models take the metal sensor directly into the GSR pipe, while most others use the supplied black plastic adapter instead. Both parts come in the kit.
A note on the eHDI and HDI versions
This whole issue was specific to blueHDI. The older 1.4L and 1.6L HDI and eHDI engines never had it — their ECUs adapt normally. If you are fitting to one of those, the eHDI installation guide is the one you want.
It took us a while to get to the bottom of this one. Thank you to the customers who reported their codes and sent photos — that is genuinely how it got solved.
Follow our GSR Induction kits Facebook and Instagram pages for new articles and updates!
Stay tuned!