P0320 on Mazda
Ignition/Distributor Engine Speed Input Circuit Malfunction
P0320 on Mazda vehicles indicates ignition/distributor engine speed input circuit malfunction. Au7o has documented this code across 2 Mazda models — most commonly on 626, Protege. The ECM/PCM detected a malfunction in the ignition or distributor engine-speed (RPM) input circuit. This circuit supplies the engine-speed reference used for spark timing and fuel control; a general fault here (open, short, or signal loss) is flagged as P0320. On distributorless systems this maps to the crank/ignition RPM reference. Typical repair costs on Mazda range from $40 to $550, depending on the specific model and root cause.
Common Causes of P0320
- •Faulty crankshaft/distributor RPM pickup sensor
- •Damaged wiring or connector in the RPM input circuit
- •Poor ground or corroded connector
- •Faulty ignition module
- •Air gap or damaged reluctor/trigger wheel
P0320 on Mazda by Model
Mazda 626(1 issue)
- KL V6 distributor internal oil seal leak / cap-and-rotor fouling1993-1999
The 2.5L KL-DE V6 uses a cam-driven distributor with an internal O-ring/oil seal at the base and a shaft bushing. As the seal hardens with age, engine oil weeps up the shaft and pools inside the distributor cap, fouling the cap and rotor and shorting the ignition. On higher-mileage cars the shaft bushing also wears, allowing shaft wobble that both worsens the leak and disturbs the pickup signal. The result is a rough-running, misfiring, hard-starting or stalling V6 that many owners chase before finding the source. This is a well-known KL-engine quirk shared with the MX-6 and Ford Probe GT.
Mazda Protege(1 issue)
- Distributor failure causing intermittent stalling and hot no-start1990-1998
First-generation Proteges (and 1.5L/1.6L second-gen cars) use a camshaft-driven distributor that houses the ignition pickup. With age these distributors suffer internal bearing wear and moisture intrusion past the seal, which corrodes the pickup and shaft. The result is a car that runs fine cold but stalls once hot and refuses to restart until it cools, or a sudden loss of spark and a crank-no-start. Documented cases include a 1990 Protege that ran ~10 minutes then abruptly stalled until cold (fixed by a dealer distributor replacement) and a 1.8L DOHC no-start where new coil, wires, cap and rotor did not cure it until the distributor was replaced.
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View P0320 across all makes →Frequently Asked Questions
What does P0320 mean on Mazda?▼
P0320 stands for "Ignition/Distributor Engine Speed Input Circuit Malfunction." The ECM/PCM detected a malfunction in the ignition or distributor engine-speed (RPM) input circuit. This circuit supplies the engine-speed reference used for spark timing and fuel control; a general fault here (open, short, or signal loss) is flagged as P0320. On distributorless systems this maps to the crank/ignition RPM reference. On Mazda specifically, this code is documented across 2 models.
What causes P0320 on Mazda vehicles?▼
Common causes on Mazda: Faulty crankshaft/distributor RPM pickup sensor, Damaged wiring or connector in the RPM input circuit, Poor ground or corroded connector, Faulty ignition module, Air gap or damaged reluctor/trigger wheel. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0320 on a Mazda?▼
Repair costs on Mazda range from $40 to $550, depending on the specific model and root cause.
Which Mazda models have P0320 documented?▼
Au7o has documented P0320 on 2 Mazda models: 626, Protege.