What was the last thing you (or someone else) did to the vehicle?
What was the exact DTC?
What was the exact DTC?
Help, Focus st boost issues!!!
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Well, strange noise under boost could be either a boost or exhaust leak.
The DTC P0238 Turbocharger Boost Sensor A Circuit High means that the PCM sees higher than reference voltage. The sensor in question houses two separate sensors. The CACT (charge air cooler sensor) measures the air temperature post intercooler and the TCBP (turbocharger boost pressure) measures the amount of pressure after the intercooler but before the throttle body.
The sensor has 4 wires. Pin1 is the SIGRTN (ground), Pin 2 is the CACT return signal to the PCM, Pin 3 is the VREF (5 VDC +), Pin 4 is the TCBP return signal to the PCM and is the offending wire.
The "high" portion on the DTC means that more than the expected voltage is being sent to the PCM. A quick test would be to disconnect the sensor and see if then code changes to "open" versus "high". *note it is important to remember that you will also see a code for the CACT because of the disconnected plug.
![382186]()
If the code remains "high" after the sensor is disconnected you could potentially have an issue with the PCM.
You said that:
You need to check the wiring on the vehicle for damage. As strange as it sounds double check the bank 1 O2 sensor wiring as I have seen the wiring become damaged on aftermarket down pipes and cause ass sorts of strange issues with the PCM.
Stay Safe
J
The DTC P0238 Turbocharger Boost Sensor A Circuit High means that the PCM sees higher than reference voltage. The sensor in question houses two separate sensors. The CACT (charge air cooler sensor) measures the air temperature post intercooler and the TCBP (turbocharger boost pressure) measures the amount of pressure after the intercooler but before the throttle body.
The sensor has 4 wires. Pin1 is the SIGRTN (ground), Pin 2 is the CACT return signal to the PCM, Pin 3 is the VREF (5 VDC +), Pin 4 is the TCBP return signal to the PCM and is the offending wire.
The "high" portion on the DTC means that more than the expected voltage is being sent to the PCM. A quick test would be to disconnect the sensor and see if then code changes to "open" versus "high". *note it is important to remember that you will also see a code for the CACT because of the disconnected plug.
If the code remains "high" after the sensor is disconnected you could potentially have an issue with the PCM.
You said that:
Did you mean that he reverted the vehicle back to stock configuration and unmarried his AP from it? Or that the tune is currently installed and he kept the AP? Sorry just seeking clarification on that one.
You need to check the wiring on the vehicle for damage. As strange as it sounds double check the bank 1 O2 sensor wiring as I have seen the wiring become damaged on aftermarket down pipes and cause ass sorts of strange issues with the PCM.
Stay Safe
J
(Example)
Cold engine (minimum 6 hours)
Set the AP to monitor BARO, MAP, TIP Actual
This test looks to see if the three related pressure sensors and in agreement or if one has failed.
Do not set the vehicle KOEO (key on engine off) * if you start the engine you will have to wait the 6 hours again.
They should be very close to one another, but note that they will not be exactly the same.
It's likely that your MAP (manifold absolute pressure) sensor has failed. It is located on the intake manifold itself. People swear the you can clean them but this issue will return.
The TMAP is mounted on the passenger side end tank of the intercooler and is responsible for reading the pressure & charge temperatures before the throttle.
The BARO reads the barometric pressure and it physically integrated into the PCM (powertrain control module) located in the drivers side fender well.
@Haranv_st Start with the test above and let us know.
J
46.81 - 14.65 = 32.16 PSI
Pretty sure you've found your problem...
Check the plug and the surrounding wires for damage. You can disconnect the sensor connector and check to see if the TIP drops to nothing. This will help to determine if your dealing with a failed TMAP or wiring issue.
Sorry ai couldn't have gotten to you before you swapped out your map sensor.
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