P0238 turbo pressure signal 1.6hdi Peugeot 307

[muresan504]

I have a problem with this error code P0238, read with my diagbox.
Car: Peugeot 307 1.6hdi 90hp year 2006
VF3**************[VIN obfuscated, can be read by forum staff]
I think the problem is the MAP sensor.
How can I check the MAP sensor? What should I follow on the live data in the diagbox to realize that the problem is the MAP sensor.
I tried to look for the diagnostic procedure in the service box but to no avail.It's the only code I get on the diagbox. When accelerating hard, a check engine appears with the anti-pollution message on board.

[GiveMeABreak]

This fault has nothing to do with your MAP sensor, it's concerning your Turbo pressure signal:

Fault Code:	P0238
Description of Fault:	Turbocharger pressure signal: Short circuit to positive. Short circuit to positive or open circuit. Value too high (Above 4.8 V)For 1,2 second.
Conditions for Fault to clear:	Ignition on
Downgrade Modes whilst Fault is active:	Default value for the air flow as a function of the engine speed and of the flow injected Inhibiting of the diagnostics and air flow sensor plausibility Cutting of the EGR butterfly (turbo air cooler), EGR valve and bypass butterfly (inlet air heater) in all operating modes
Symptoms:	Noise Diesel fuel consumption a bit higher Lack of power
Suspect Areas:	Turbocharging pressure sensor Turbocharger position copy sensor Vacuum problem Variable geometry of the turbocharger jammed in the "maximum turbocharging" position Faulty turbocharger

[muresan504]

We take the turbo out of the calculation. The old turbo of the car started to have a little play in the shaft and to lose a little oil. I replaced the turbo with a new one. But the error code persisted before with the old turbo and now with the new turbo.
So should I check the vacuum storms, and which sensors should I check? I thought the Turbocharging pressure sensor was the MAP sensor. Can you help me with a picture of what these sensors look like
"Turbocharging pressure sensor
Turbocharger position copy sensor"

[muresan504]

I knew that the MAP sensor is the one surrounded in red. Which as far as I know is supposed to be the Turbocharging pressure sensor

[muresan504]

I will check the vacuum hoses, if I keep getting under the car I will activate it from the diagbox and the electrovalve should vibrate if it is functional. What else should I check?

[GiveMeABreak]

I'm a little busy elsewhere on the Forum assisting others, but will get back on this as soon as I can...

[muresan504]

Ok

[GiveMeABreak]

From what I can make out, the sensor circled red is the Inlet Air Pressure Sensor & the one circled in yellow is the Air Intake Temperature Sensor.

Here's a diagram of the system so you can check the circuit and see where the turbo control solenoid is etc.

Key:
"E": Air circuit
"F": Exhaust gas
"G": Duct crossing the engine block

Reference	Designation
(26)	Exhaust gas recycling (EGR) heat exchanger
(27)	Exhaust gas recycling (EGR) regulation electrovalve
(28)	Air cleaner
(29)	Air inlet manifold
(30)	Air flow meter
(31)	Inlet air pressure sensor (oversupply)
(32)	Inlet air heater throttle (RAA)
(33)	EGR butterfly
(34)	Variable geometry turbocharger
(35)	TURBOCHARGING AIR COOLER (RAS)
(36)	Vacuum reservoir
(37)	Catalytic converter / Particulate emission filter (pef)
(38)	Vacuum pump
(39)	Turbocharger control solenoid valve

[muresan504]

1. I checked the wiring from the MAP sensor/Inlet Air Pressure Sensor and I saw a value of 5v, so the wiring is ok.
2. I checked the vacuum hoses from the Turbocharger control solenoid valve and they are ok.
3. I checked the Turbocharger control solenoid valve which, according to the live data from the diagbox, works, and raises the turbocharger actuator during acceleration.
In the end, I found that the problem is the MAP/Inlet Air Pressure Sensor, I will buy one from Denso.
1920CZ is the OE code.

[muresan504]

Is there any way to test the old sensor? Before I buy the new one

[GiveMeABreak]

Not really if it is damaged internally.

[muresan504]

I replaced the map sensor without any changes. The same code P0238 turbo pressure signal

[muresan504]

[muresan504]

It's very strange, because it's an intermittent code that only appears during strong acceleration. The car does not go into limp mode. The code is cleared with the diagbox, but it appears again when I accelerate strongly.

[muresan504]

Could gas leaking from the exhaust manifold trigger this code?