DS3 1.6hdi Engine AIR codes

[dylan26__]

Hi all, Just had these codes when driving. i've cleared them a couple times, some days it comes back some days it doesn't, sometimes it can come back almost immediately after clearing them.

P0100
P3026
P3008

My thoughts that maybe it is the MAF that is showing incorrect values? Other than that i can only think perhaps it's something to do with the turbo waste gate actuator which i really hope its not!
VF7**************[VIN obfuscated, can be read by forum staff]

[GiveMeABreak]

Fault Code:	P0100
Description of Fault:	Air flow measure: Quantity of air above the maximum threshold. Description of the diagnostics Possibility 1 For an engine speed between 2000 and 3000 rpm : Measured air flow greater than 1160 mg/stroke for 3 s Possibility 2 For an engine speed at 3500 rpm : Measured air flow greater than 1050 mg/stroke for 3 s Possibility 3 For an engine speed at 4000 rpm : Measured air flow greater than 970 mg/stroke for 3 s Thresholds indicated for an altitude of 0 m and an ambient temperature of 20 °C they are weighted according to altitude and temperature. Conditions of activation of the diagnostics: The following conditions have to be met -Engine running -Battery voltage between 8 and 16 V
Conditions for Fault to clear:	3 drives in succession for 5 minutes with several full load accelerations for 10 seconds (Ignition off and restarting between each drive)
Downgrade Modes whilst Fault is active:	Closing of the EGR (exhaust gas recycling) valve Irreversible deactivation of the vehicle speed limiter Irreversible deactivation of the vehicle cruise control Switching of the turbocharging pressure regulation to controlled mode Deactivation of the request for regeneration of the particle filter from the diagnostic tool Sending of the information "torque uncertain" on the CAN network Switching on of the warning lamp and/or warning message: Warning lamp MIL: "SERVICE" warning lamp
Symptoms:	Jerking/stalling Noise Lack of power Slightly higher fuel consumption Smoke from the exhaust Absence of automatic stopping of the internal combustion engine (If the vehicle has the Stop and Start system) Problem with automatic restarting of the internal combustion engine (If the vehicle has the Stop and Start system)
Suspect Areas:	Atmospheric pressure sensor in the engine management ECU Manifold air entry pressure sensor Air flow meter Leak between turbocharger and air mixer Leak between the air mixer and the engine intake (including the EGR valve take-off) Leak on the air mixer Leak on the turbocharging air cooler Turbocharger Turbocharger variable geometry control solenoid valve Turbocharger variable geometry position repeat sensor Electrical harnesses Connectors

Fault Code:	P3026
Description of Fault:	Air circuit: Air flow higher than recommended (Service). Ratio of the measured air flow to the theoretical air flow calculated greater than 15 %, detected for 2,5 seconds. Conditions of activation of the diagnostics: The following conditions have to be met - In the pedal release phase - Air temperature higher than -20°C - Battery voltage between 10 and 16 V - Turbo pressure between 750 and 1500 mbars - Engine coolant temperature between 40 and 110 degrees C - Engine speed between 1200 and 2500 rpm - Air mixer open - Exhaust gas recirculation valve closed for more than 2 seconds
Conditions for Fault to clear:	Driving for 5 minutes with decelerations of more than 10 seconds
Downgrade Modes whilst Fault is active:	-
Symptoms:	Jerking/stalling Noise Lack of power No automatic stopping of the internal combustion engine (Vehicle equipped with "stop and start") Slightly higher fuel consumption Smoke from the exhaust Fluid leak/smells (diesel fuel, oil, etc.) Engine overheating with illumination of the engine coolant temperature indicator light Problem with automatic restarting of the internal combustion engine (Vehicle equipped with "stop and start")
Suspect Areas:	Atmospheric pressure sensor in the engine management ECU Air flow meter Air leak between turbocharger and mixer Leak on the turbocharging air cooler Leak between the air mixer and the engine intake (including EGR inlet point) Leak on the air mixer Air leak on the turbocharger housing Air leak on the EGR exchanger with by-pass Turbocharger variable geometry position repeat sensor Manifold air entry pressure sensor Electrical harnesses Connectors

Fault Code:	P3008
Description of Fault:	Air circuit: Air flow higher than recommended. Ratio of the measured air flow to the theoretical air flow calculated greater than 18 %, detected for 2,5 seconds. Conditions of activation of the diagnostics: The following conditions have to be met - In the pedal release phase - Air temperature higher than -20°C - Battery voltage between 10 and 16 V - Turbo pressure between 750 and 1500 mbars - Engine coolant temperature between 40 and 110 degrees C - Engine speed between 1200 and 2500 rpm - Air mixer open - Exhaust gas recycling valve closed (For more than 2 s)
Conditions for Fault to clear:	Driving for 5 minutes with decelerations of more than 10 seconds
Downgrade Modes whilst Fault is active:	Closing of the EGR (exhaust gas recycling) valve Switching of the turbocharging pressure regulation to controlled mode Deactivation of the request for regeneration of the particle filter from the diagnostic tool Sending of the information "torque uncertain" on the CAN network Switching on of the warning lamp and/or warning message: Warning lamp MIL
Symptoms:	Jerking/stalling Noise Lack of power Absence of automatic stopping of the internal combustion engine (Vehicle equipped with "stop and start") Slightly higher fuel consumption Smoke from the exhaust Fluid leak/smells (diesel fuel, oil, etc.) Engine overheating with illumination of the engine coolant temperature indicator light Problem with automatic restarting of the internal combustion engine (Vehicle equipped with "stop and start")
Suspect Areas:	Atmospheric pressure sensor in the engine management ECU Air flow meter Air leak between turbocharger and mixer Leak on the turbocharging air cooler Leak between the air mixer and the engine intake (including EGR inlet point) Leak on the air mixer Air leak on the turbocharger housing Air leak on the EGR exchanger with by-pass Turbocharger variable geometry position repeat sensor Manifold air entry pressure sensor Electrical harnesses Connectors

[RichardW]

Used to get something similar on our C4 Picasso after I fitted a new EGR - could almost guarantee it would come on if you accelerated hard and then let the throttle close quickly. Never got to the bottom of why it did it!

[GiveMeABreak]

Use a blindfold and take your pick from that list!

[dylan26__]

Oh god that's so many options of things to go wrong
I had my thermostat explode during my MOT last week and then replaced that. Ovbiously the airflow meter is right above that, think maybe it could have affected it? I've cleaned off the sensor best I could and it seemed to fix it for a few days but has now come up again

[GiveMeABreak]

MAFs are very sensitive bits of equipment so it is a distinct possibility.

The codes are just to provide some guidance, so look for the most obvious first - if you think the MAF has had water damage, then focus on this first as it can cause other issues and fault codes.

[Rp0thejester]

If your lacking power I would say the MAF is the first thing to check. Are there certain symptoms whilst your driving?

[dylan26__]

If your lacking power I would say the MAF is the first thing to check. Are there certain symptoms whilst your driving?

As of recently since the thermostat had been replaced if I give the car very light throttle in between 1200-2000rpm when driving it feels like it's missfiring as gets a bit jerky. If I give it more on the accelerator it's absolutely fine. When the codes come up the car occasionally becomes limited to 3000rpm and power is not there which I'm assuming is just a limp mode

[Rp0thejester]

Easiest check to make is to disconnect the MAF sensor, go for a drive, EML will probably come on but not an issue and see if the performance improves. If not, it's not the MAF or unlikely to be

[dylan26__]

Easiest check to make is to disconnect the MAF sensor, go for a drive, EML will probably come on but not an issue and see if the performance improves. If not, it's not the MAF or unlikely to be

Will go for a drive just now and give an update after, cheers guys

[dylan26__]

Easiest check to make is to disconnect the MAF sensor, go for a drive, EML will probably come on but not an issue and see if the performance improves. If not, it's not the MAF or unlikely to be

It's a bit weird really. The engine light did not come on when I disconnected the maf and drove for 30 minutes or so. I turned the engine off and on again with it disconnected and it immediately popped up with the engine light and those codes again. I cleared it and drove home and again no lights have come on, no codes other than Saying the maf is disconnected.

I plugged it back in and alas still no codes. I'm wondering if the immediate code was related to something else. I mean realistically the maf shouldn't have got any coolant on it, just would have got pretty humid and hot around there.

To replace the thermostat the ECU and battery tray had to be removed but doubt that would have anything to do with the air flow.

[Rp0thejester]

Was there a difference in performance after the MAF was disconnected?

[dylan26__]

Was there a difference in performance after the MAF was disconnected?

Seemed a little bit slower and the cruise / limiter didn't work

[GiveMeABreak]

That is to be expected as the engine ECU puts the vehicle into backup mode and disables some functions (including cruise control / limiter) as it knows there is an air / fuelling problem.

[dylan26__]

That is to be expected as the engine ECU puts the vehicle into backup mode and disables some functions (including cruise control / limiter) as it knows there is an air / fuelling problem.

i thought this much. But yeah i will try go for a drive again tonight with the maf disconnected to see if the code throws again. just to double check and then hopefully it will be just that. Otherwise i will just record the live data with the maf attached and see what happens