P0243
Turbocharger/Supercharger Wastegate Solenoid A
If your vehicle's onboard computer has flagged the diagnostic trouble code P0243, it refers to a detected anomaly regarding "Turbocharger/Supercharger Wastegate Solenoid A". This systemic engine fault needs a targeted check before symptoms expand.
Driver's Summary
Storing code P0243 is your car's way of telling you something is wrong with the turbocharger/supercharger wastegate solenoid a. On the road, this usually shows up as lack of power, engine surging, check engine light, erratic boost. This is a moderate-severity fault — plan a repair shop visit within the week to keep it from escalating.
Symptoms
Lack of power, engine surging, check engine light, erratic boost
Common Causes
- Defective wastegate solenoid
- Open or shorted solenoid wiring
- Clogged or leaking vacuum lines
- Damaged wastegate actuator
How to Fix
- 1 Test and replace wastegate solenoid
- 2 Repair solenoid wiring harness
- 3 Replace restricted vacuum lines
- 4 Inspect wastegate actuator operation
Technical Explanation
The PCM triggers P0243 after its internal monitoring routine detects that a specific circuit or sensor has exceeded its acceptable operating range. The PCM monitors crankshaft rotational velocity via the CKP sensor at a resolution of individual tooth gaps on the reluctor ring. A combustion event in each cylinder produces a measurable acceleration spike; its absence or weakness is flagged as a misfire event within a 200-revolution or 1000-revolution test window. After two failed drive cycles, the code transitions from a pending to a confirmed DTC, and the PCM activates the MIL. Clearing the code without repairing the fault will result in re-illumination within one to two complete drive cycles.
Is It Safe to Drive?
Medium-severity fault: the car functions but not optimally. The defective wastegate solenoid issue will not resolve itself and will cause measurable long-term wear. A repair in the $80–$350 range now avoids far higher costs later.
Mechanic's Pro Tip
Before replacing any component on P0243, spend 5 minutes inspecting the wiring harness and connector first — corrosion, chafed insulation, and backed-out pins cause the majority of these faults and cost nothing to fix. Use a multimeter to measure voltage drop across the connector pins under load; anything above 0.1V indicates excessive resistance that will cause intermittent failures even after replacing the sensor.
Solenoid: $80 - $200; Labor: $150