C3393 Engine Trouble Code
What is C3393?
C3393 indicates potential catalytic converter failure. If completely failed, your vehicle may not run properly and fuel economy will suffer significantly. Average replacement cost is $2,000–$2,140. This repair requires professional service and should not be delayed.
Code Information
| Code Type: | OBD-II Chassis (C) Trouble Code |
| System: | Chassis |
| Code: | C3393 |
C3393 Symptoms
Check Engine Light
Illuminated dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration
Starting Problems
Difficulty starting the engine
C3393 Code Structure
Understanding what each digit means in the C3393 chassis trouble code:
| C | 3 | 3 | 9 | 3 |
|---|---|---|---|---|
| Chassis Code | Ignition System Or Misfire | Throttle/Pedal Position Sensor/Switch A Circuit Intermittent | Crankshaft Position Sensor A Circuit Malfunction | Exhaust Gas Recirculation Sensor B Circuit High |
How to Fix C3393
Diagnostic Steps:
The catalytic converter has oxygen sensors before and after it. When warm and in closed-loop mode, the upstream O2 sensor reading should fluctuate, while downstream should remain steady.
Repair Solution:
Gasoline engines use spark plugs to ignite fuel-air mixture. Proper timing ensures the explosion occurs when the piston is positioned correctly. Incorrect plug wire sequencing causes mistimed ignition, resulting in poor performance.
Technical Notes:
C3393 DTC specifically relates to camshaft timing. When cam timing is over-retarded, the check-engine light illuminates and this code sets. Verify VCT solenoid operation and check for contamination.
C3393 Description
C3393 engine trouble code is related to Exhaust Gas Recirculation Sensor B Circuit High.
Main Cause
The primary reason for C3393 OBD-II Engine Trouble Code is: Throttle/Pedal Position Sensor/Switch A Circuit Intermittent.