Variable Resonance Induction System Solenoid Valve 1 Malfunction
Table of contents
P1521 MAZDA Possible Causes
- Faulty Variable Resonance Induction System (VRIS) Solenoid Valve 1
- Variable Resonance Induction System Solenoid Valve 1 harness is open or shorted
- Variable Resonance Induction System Solenoid Valve 1 circuit poor electrical connection
- Faulty Powertrain Control Module (PCM)
How do I fix code P1521 MAZDA?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
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Cost of diagnosing the P1521 MAZDA code
The cost of diagnosing the P1521 MAZDA code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P1521 MAZDA Description
Three solenoid-operated shutter valves are installed in the dynamic chamber of the Variable Resonance Induction System (VRIS). The VRIS opens and closes the shutter valves according to the engine speed and throttle opening angle to improve the charging efficiency by utilizing the pressure waves of the intake air There are two vacuum chambers located under the front (LH) bank of the intake manifold. These vacuum chambers maintain a constant supply of vacuum to the VRIS shutter valves during wide-open throttle operation and other low-vacuum, low-speed situations. The Diagnostic Trouble Code (DTC) is set when the Powertrain Control Module (PCM) detects low input voltage from VRIS solenoid valve No. 1 system with ignition switch on. This is a continuous monitor. MIL will not illuminate.