P1445 Code: Evaporative Purge Control Fault (Manufacturer Code)

What the P1445 code means

The vapor control system traps in an activated carbon canister the gases that evaporate from the fuel tank. Those vapors are not thrown away: when the engine is in the right conditions, a valve lets them into the intake so they get burned. That process is called purging.

The computer runs that valve with precision, because sending vapors at the wrong moment upsets the mixture. At idle, for example, too much purge can make the engine run rough or stall.

The P1445 code flags a fault in that control. It is a manufacturer code and its definition varies slightly: on Nissan and Infiniti it refers to the solenoid that regulates the purge volume; on vehicles from the PSA group, to a high signal from the purge flow sensor; and in the BMW group, MINI included, to the canister purge valve circuit.

All three descriptions point to the same group of parts, so the diagnosis is the same: valve, hoses, flow sensor if there is one, and the electrical circuit that ties them together.

It helps to know why the system does not purge at just any time. The canister vapors are fuel, so sending them to the intake changes the mixture. If that happened at a cold idle, when the engine is already running a richer mixture, the result would be a rough idle or a stall.

That is why the computer waits until the engine is warm, in closed loop and under some load before it opens the valve, and it does so gradually while compensating with the injectors. Understanding that logic explains the classic symptom of a valve stuck open: roughness at exactly the moment the system was not expecting to receive vapors.

P1445 code symptoms

• Check engine light on.
• Rough idle, or an engine that stalls when you come to a stop.
• A noticeable fuel smell.
• Higher fuel use.
• Trouble filling the tank, with the pump nozzle clicking off early.
• The EVAP monitor does not reach ready status.
• Failed emissions test.
• Hard starting after refueling.
• The roughness is concentrated at cold idle and goes away once the engine is warm.

Likely causes of the P1445 code

1. Purge valve failed or stuck, open or closed. The most frequent cause.
2. System hoses cracked, disconnected or crushed.
3. Purge flow sensor defective, on vehicles that have one.
4. Carbon canister saturated or damaged.
5. Connector corroded or with backed-out pins.
6. Circuit wiring damaged.
7. Gas cap with a worn seal.
8. Tank habitually overfilled, which soaks the canister with liquid fuel.
9. Blown fuse in the circuit.

How to diagnose the P1445 code step by step

1. Locate the purge valve, usually in the engine compartment near the intake.
2. Command the valve with an active test and listen for the click. No click points to the circuit or to the valve itself.
3. Blow through the valve with the engine off. At rest it must be closed and let no air pass.
4. Measure its resistance with the connector unplugged and compare it with the specification.
5. Inspect the hoses along their whole length for cracks, kinks and loose connections.
6. Check power and ground at the connector.
7. Watch purge flow in live data if the vehicle reports it.
8. Check the gas cap and its seal.
9. Note whether the roughness shows up at cold idle, which is when the system should not be purging at all.

How to fix the P1445 code

• Replace the purge valve if it is stuck or its resistance is out of range.
• Replace cracked or crushed system hoses.
• Replace the purge flow sensor if its signal does not match actual operation.
• Replace the canister if it is soaked with liquid fuel or damaged.
• Clean or replace the corroded connector and protect it with dielectric grease.
• Repair the circuit wiring.
• Replace the gas cap if its seal is worn.
• Avoid filling the tank past the first click of the pump.
• After the repair, check that the purge only activates with the engine warm and in closed loop.

Topping off the tank pushes liquid fuel toward the canister, which is designed for vapors. Doing it over and over kills the part, and it is an avoidable cause.

Technical reference data

• Typical purge valve resistance: 20 to 40 ohms.
• Purge valve resting state: closed. It only opens when the system commands it.
• Purge is not active at cold idle or in the first minutes after startup.
• The EVAP test requires the tank to be between 15 and 85 percent full.
• Nissan and Infiniti define it as the purge volume control solenoid; the PSA group defines it as the purge flow sensor.
• Purge activates with the engine warm, in closed loop and under some load, never at cold idle.

Brand-specific notes

A purge valve stuck open produces a very recognizable symptom: the engine runs rough at idle and smooths out when you accelerate, because vapors flow in constantly instead of only when they should. If the idle also steadies when you pinch the purge hose, the diagnosis is closed.

The habit of topping off the tank, squeezing the pump after the first click, pushes liquid fuel into the canister. It is an avoidable cause that shortens the life of that part a lot, and it is worth warning drivers about it.

P1445 on Nissan and Infiniti

The definition is the solenoid that controls the purge volume.

P1445 on PSA Group Vehicles

The definition is a high signal from the purge flow sensor.

P1445 on BMW and MINI

The definition is a fault in the canister purge valve circuit.

Frequently asked questions about P1445