Hello, I keep getting a P0110 code on my 05 CRD which then shows both P0110 & P0105 codes. I can delete them but they both come back almost immediately. I changed the Map sensor which helped for a day. Then the issue came back. I have rebuilt top end 1.5 years ago by JoshCRD, EGR delete & GDE tune.

What controls the P0110 code. This is for intake temperature circuit which I can't find separate sensor for. Everything I read says it is controlled by map sensor. Once P0110 fault is set then P0105 follows quickly. Is it wiring, sensor or ECM?

P0105 -- Manifold absolute pressure (MAP) sensor/barometric pressure (BARO) sensor – circuit malfunction Wiring, MAP sensor, BARO sensor, ECM
The MAP sensor is a combined intake air temperature sensor and an intake air pressure sensor

P0110 -- Intake air temperature (IAT) sensor – circuit malfunction Wiring, IAT sensor, ECM
The IAT is the turbo inlet (air box) pressure sensor.
IAP sensor – OEM part no.: 05101120AB (intake air pressure sensor on side of airbox)
air inlet air pressure comparator pressure sensor on the side of the air box;
sometimes referred to as the “Mercedes sensor”

Check your wiring and sensor connections and make sure you don't have a loose (bad) connection or a chaffed wire somewhere.



IAP SENSOR

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Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
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Carter Intank-pmp
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GM11 Bld.fan/HDClutch
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98 Dodge Cummins 24 Valve

First you said that the MAP sensor is the IAT & IAP combined. Then you say the MAF ( turbo inlet sensor) is the IAT. Which is it. I believe it is MAP sensor. MAF sensor is only air flow.

What I said was correct, read my post again and study the picture!

The MAP sensor senses the intake manifold boost pressure and air temperature inside the intake manifold.
The IAT sensor senses the air pressure inside the air filter box on the inlet to the turbo.
They are totally separate and different sensors with different functions!

Never said anything about the MAF sensor, it has nothing to do with the DTC's (P codes) you said are getting. It only senses air flow for EGR system operation.

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

Hi mate, Im trying to understand the purpose of measuring the air pressure inside the air filter box. Wont the inlet air pressure potentially change dramatically by the time it actually reaches the engine due to other pressure drops in the intake such as the intercooler, and also by the turbo creating a wide variety of boost pressure changes by the time the engine sees it?
Cheers

G'day to you mate!
Not 100% sure of the purpose of the IAP sensor in the air filter box. Marco (Yeti) could probably provide a more detailed answer as to its purpose?
It is used on some other diesel engines with the Bosch injection system.
The ECM may need to know the air density coming into the turbo inlet in order to calculate the correct amount of fuel to be injected for the correct air fuel ratio?
Yes, the pressure changes, but the air density's affects would be the same through the whole intake system I would think.
Just my old power plant operators guess!

Having operated large boilers/turbines for over 40 years, I know first hand how air density (pressure) can greatly affect boiler operation, so I would think it would be very similar in a turbo charged engine?

_________________
Supporting Vendor and Moderator of LOST
05 Jeep Liberty CRD Limited
Ironman Springs/Bilstein/Shocks
Yeti StgIV Hot Tune
Week's BatteryTray
No FCV/EGR
Samcos/ProVent
SunCoast/Transgo
Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
IronrockArms/wwdieselMount
98 Dodge Cummins 24 Valve

there is some confusion
the Intake Air Temperature sensor is a part of the MAP , Manifold Absolute Pressure
P0110 is IAT failure and P0105 MAP sensor circuit open or shorted to ground ,if you have changed the MAP sensor check the entire wiring from sensor to ECU

the other map sensor on the side of the air box cover is needed for read the atmospheric pressure and help the ecu to calculate the engine load

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ECU Tuner -EGR OFF -DPF OFF Swirl/Flap OFF, Lambda OFF , DTC OFF in many cars , not ONLY

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Hi mate thanks for that, I suspected the map sensor on the airbox was probably to measure the atmospheric pressure.
So is it just plumbed into the airbox in order to ensure that it stays clean? And if so, does this mean it would function just as intended regarding calculating engine load even if it is removed from the airbox and just sitting loose in the engine bay for example? (Obviously disregarding the cleanliness factor)

Cheers mate

it read the vacuum for calculate the load than must be installed after the air filter

_________________
ECU Tuner -EGR OFF -DPF OFF Swirl/Flap OFF, Lambda OFF , DTC OFF in many cars , not ONLY

https://www.facebook.com/YetiChiptuning