Faulty or drifting intake air temperature sensor 3 giving an implausible reading; Corroded, loose or damaged connector terminals at the sensor; Damaged, chafed or high-resistance wiring between the sensor and control module; Sensor exposed to heat soak or poorly mounted, so it reads differently from the actual air temperature; Fault in the intake or charge air system, such as a leaking or heat-affected intercooler pipe, causing a genuine temperature mismatch; Faulty reference voltage or ground supply shared with other sensors; Fault inside the powertrain control module.

P00E9

Intake Air Temperature Sensor 3 Circuit Range/Performance Bank 1.

Generic
Powertrain
Generic code
Low severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
0: AreaFuel and air metering, auxiliary emission controls
E9: FaultThe specific fault in that area

What it means

P00E9 is a generic code meaning the powertrain control module has found a range or performance fault with intake air temperature sensor 3 on bank 1. The sensor's signal is within the electrical limits but does not make sense against other data, for example it reads implausibly high or low compared with ambient or other temperature sensors, or it barely changes when it should. Which position 'sensor 3' refers to varies by model and engine, so check the manufacturer's information for its location.

Symptoms

Engine warning light on
Slightly rough running or hesitation, particularly on a cold start
Poor fuel economy
Reduced power or turbocharger boost limited on some engines
Hard starting in cold or hot conditions
Unusual intercooler or charge air temperature readings on a scan tool

Possible causes

Faulty or drifting intake air temperature sensor 3 giving an implausible readinglikely
Corroded, loose or damaged connector terminals at the sensorlikely
Damaged, chafed or high-resistance wiring between the sensor and control modulepossible
Sensor exposed to heat soak or poorly mounted, so it reads differently from the actual air temperaturepossible
Fault in the intake or charge air system, such as a leaking or heat-affected intercooler pipe, causing a genuine temperature mismatchpossible
Faulty reference voltage or ground supply shared with other sensorsrare
Fault inside the powertrain control modulerare

How to diagnose

Read all stored codes and freeze frame data, noting engine temperature, load and ambient conditions when the fault set
Check for other temperature sensor or charge air codes that point to a shared wiring or supply fault
Visually inspect the sensor, connector and wiring for damage, corrosion, water ingress, chafing or heat damage
With the engine cold and left off for several hours, compare sensor 3 live data with the other intake air, coolant and ambient temperature readings; they should be close
Watch the live reading while starting and warming the engine to see whether it responds smoothly and plausibly or sticks and jumps
Check the sensor's resistance against the manufacturer's temperature table and test the wiring for continuity, shorts and voltage drop
Inspect the intake and charge air pipes, intercooler and sensor mounting for leaks, damage or anything that could affect the reading
Check the reference voltage and ground at the connector with the sensor unplugged, following the model's wiring diagram

How to fix

Replace intake air temperature sensor 3 if its readings or resistance are out of specification
Clean or repair corroded terminals and secure the connector properly
Repair or replace damaged wiring between the sensor and control module
Refit or correct the position of the sensor so it measures the true air temperature
Repair leaking or damaged intake or charge air components that cause a genuine temperature mismatch
Repair the supply or ground fault, or have the control module checked, only after the wiring and sensor have been ruled out

Can I keep driving?

Low severity

The car can usually be driven for a short time while you book it in, as the engine normally falls back on default temperature values. If power is noticeably reduced or the engine runs poorly, have it checked sooner.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.