P1345 — Injector Circuit / IDM Codes Detected

Is it safe to drive with P1345?

Drive with caution. Mixture and fuel-pressure faults can cause stalling, hesitation in traffic and — when severe — catalyst damage. Avoid long trips until diagnosed.

How do I diagnose P1345 myself?

Start with a scan: confirm P1345, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the injector circuit / IDM codes, and verify the suspect component against live data before buying parts.

What are the symptoms of P1345?

Drivers most often notice: increased fuel consumption, Check Engine Light on, rough idle and hesitation, hard starting or long cranking.

How much does it cost to fix P1345?

Clean or replace injectors — $200–$800; Replace the fuel pump — $400–$900; Replace the pressure regulator or sensor — $150–$450; Replace the fuel filter — $80–$200. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

What does OBD2 code P1345 mean?

Injector Circuit / IDM Codes Detected (P1345): a powertrain (engine/transmission) fault affecting the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Most often caused by faulty fuel pressure regulator, clogged or leaking fuel injectors, contaminated or incorrect fuel.

When your OBD2 scanner pulls code P1345, it's flagging a problem in the engine's fuel delivery and mixture control system. Specifically, the powertrain control module has detected injector circuit irregularities or IDM (Injector Drive Module) fault codes that fall outside standard injector-specific categories. This code lives in the powertrain family because it directly affects how your engine meters fuel and manages the air-fuel mixture.

The control module constantly monitors fuel delivery and mixture control sensors against factory-calibrated thresholds. When readings drift outside acceptable limits over multiple drive cycles, the module stores P1345 alongside a freeze frame—a snapshot capturing rpm, engine load, coolant temperature, and vehicle speed at the moment of failure. Reviewing that snapshot before diving into diagnostics tells you exactly what conditions triggered the fault, saving considerable diagnostic time.

Fuel injectors atomize gasoline into the intake ports or combustion chambers, and the IDM coordinates firing signals while the ECU adjusts pulse width based on oxygen sensor feedback. When this chain breaks down—whether from electrical faults, pressure problems, or mixture imbalances—the control module detects the anomaly and sets P1345 to alert you that something in the fuel management system needs attention.

Common Symptoms of P1345

P1345 produces several noticeable driveability issues:

• Noticeably higher fuel consumption than usual
• Check Engine Light remains illuminated
• Engine runs roughly at idle with hesitation during acceleration
• Extended cranking time when starting the engine
• Reduced engine power when climbing hills or under heavy throttle
• Strong fuel odor, particularly in more severe cases

What Triggers P1345

Multiple fuel system faults can trigger P1345. The most common culprits include:

• Clogged or leaking fuel injectors disrupting proper fuel delivery
• Weak fuel pump or clogged fuel filter preventing adequate pressure
• Faulty fuel pressure regulator causing pressure swings
• Vacuum or intake leaks introducing unmetered air into the mixture
• Contaminated or incorrect fuel type degrading combustion

Diagnosing P1345

Follow these steps to pinpoint the root cause:

1. Connect an OBD2 scanner and confirm P1345 is stored. Save the freeze frame data immediately—it shows the exact engine conditions when the fault occurred.
2. Look for related trouble codes alongside P1345. Companion codes often reveal the actual failing component. Also search manufacturer technical service bulletins (TSB) for your make and model—factory fixes or software updates may already exist. Search by VIN on the manufacturer website or nhtsa.gov.
3. Perform a visual inspection of the wiring harness and connectors feeding the fuel delivery and mixture control system. Look for damaged insulation, corrosion, chafing from rubbing against engine components, or loose fitting connectors.
4. Measure fuel rail pressure with a gauge and compare against factory specifications at idle and under simulated load conditions.
5. Monitor short-term and long-term fuel trims in live data mode. Significantly positive or negative trims confirm the mixture is off-target in a specific direction.
6. Clear the code and drive through a complete drive cycle that reproduces the freeze frame conditions. Confirm P1345 does not return before considering the repair complete.

Repair Options for P1345

Address the cheapest and most frequent failures before investing in expensive components:

• Clean or replace fuel injectors — $200–$800
• Replace fuel pump — $400–$900
• Replace fuel pressure regulator or sensor — $150–$450
• Replace fuel filter — $80–$200

Total Cost to Fix P1345

Your actual repair bill depends entirely on which component failed. Parts and labor costs at independent shops typically break down as follows:

• Injector cleaning or replacement runs $200–$800 depending on whether you clean existing injectors or buy new ones
• Fuel pump replacement costs $400–$900 including parts and labor
• Pressure regulator or sensor replacement runs $150–$450
• Fuel filter replacement is the most affordable option at $80–$200

Most drivers end up spending between $80 and $900 to resolve P1345. The key money-saving strategy: perform thorough diagnosis before purchasing parts. The fuel filter is a cheap first step that sometimes solves the problem, while the fuel pump represents the most expensive scenario and should be checked last.

Can You Drive with P1345?

P1345 warrants caution. Fuel mixture and pressure faults can produce dangerous stalling, hesitation in traffic situations, and reduced power when you need it most. In severe cases, unburned fuel washing past the catalytic converter can cause heat damage to that expensive emissions component. Avoid long highway trips until you've identified the root cause. Get the code diagnosed promptly and limit driving to essential trips until you know exactly what's wrong.

Related OBD2 Codes

• P1300: Multi-faults - Bank 1 - With Low Side Shorts
• P1301: Multi-faults - Bank 2 - With Low Side Shorts
• P1302: Injector High Sides Shorted Together
• P1303: IDM Failure
• P1304: Cylinder Head Overtemperature Protection Active
• P1305: Boost Calibration Fault