P1440 on Acura: How to Diagnose & Fix
EVAP Canister Purge System Small Leak (Positive Pressure)
1 Acura model · 1 documented issue · 1 critical · $2,000-$4,000 repair
P1440 on Acura by model: symptoms, diagnosis and fix
The ILX Hybrid used the Civic Hybrid's Integrated Motor Assist system - a 1.5L engine with a thin motor-generator between engine and CVT and a nickel-metal-hydride IMA battery pack. It sold in tiny numbers for only two model years and was dropped after 2014. The IMA pack degrades: individual cell sticks fall out of balance, capacity drops, the state-of-charge display swings wildly from full to empty, assist and regen are cut, and the IMA warning light and check engine light illuminate. Acura acknowledged the pattern with Service Bulletin 12-012 (revised June 2015) establishing an IMA Battery Exchange Program covering ILX (and RLX Sport Hybrid) IMA batteries for any internal failure requiring module disassembly - explicitly including out-of-warranty vehicles. Owners also report a second, separate problem: repeated 12V accessory battery failures and no-crank conditions, which on an IMA car is often a symptom of the hybrid system not charging the 12V properly rather than a bad 12V battery.
Common Symptoms
- IMA warning light illuminated
- Check engine light
- State of charge gauge swings rapidly between full and empty
- Loss of electric assist and regenerative braking
- Reduced fuel economy
- Repeated 12V accessory battery failure
- No crank / will not start requiring a jump
How to Fix
Have the dealer read the IMA system codes and run a battery capacity/module test before buying anything. Acura Service Bulletin 12-012 (IMA Battery Exchange Program) is the lever - it covers internal IMA battery failures including out-of-warranty cars and should be quoted by number when the service writer says the car is too old. A battery-management recalibration update was also released for IMA cars that changes charge/discharge management and can restore usable capacity on a marginal pack. Full IMA pack replacement runs roughly $2,000-$4,000; reconditioned packs are available for less. If the complaint is repeated 12V battery death, diagnose the DC-DC converter and parasitic draw before replacing the 12V again.
Sources for this issue (3)
P1440 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P1440 mean on a Acura?
P1440 stands for "EVAP Canister Purge System Small Leak (Positive Pressure)." Nissan's ECM pressurizes the EVAP system and monitors the fuel tank pressure sensor for decay. P1440 indicates a leak or malfunction in the canister purge system detected under positive pressure. Driveability is normally unaffected but the vehicle will fail an emissions test. On Acura it is documented across 1 model: ILX.
What are the most common causes of P1440?
The most common causes of P1440 are: Loose or failed fuel filler cap, Cracked or disconnected EVAP hoses, Failed EVAP canister vent control valve, Failed EVAP canister purge volume control valve, Failed fuel tank pressure sensor, Cracked charcoal canister. The specific cause varies by vehicle.
How much does it cost to fix P1440 on a Acura?
Published repair estimates on Acura range from $2,000 to $4,000 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P1440 on a different make?
View P1440 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.