B0074 Engine Trouble Code
What is B0074?
B0074 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 Body (B) Trouble Code |
| System: | Body |
| Code: | B0074 |
B0074 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
B0074 Code Structure
Understanding what each digit means in the B0074 body trouble code:
| B | 0 | 0 | 7 | 4 |
|---|---|---|---|---|
| Body Code | Intake Valve Control Solenoid Circuit Low | Ambient Air Temperature Sensor Circuit Low | Cylinder 10 Contribution/Balance Fault | Timing Reference High Resolution Signal A Too Many Pulses |
How to Fix B0074
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:
Excessive air inflow may result from vacuum leaks, dirty sensors, or EGR valves not closing properly. Insufficient fuel can stem from dirty injectors, clogged filters, weak fuel pump, or leaking pressure regulator.
Technical Notes:
B0074 DTCs can be triggered by upstream issues. For example, a dirty MAF sensor may cause incorrect fuel-trim adjustments, leading oxygen sensors to report mixture problems. Address root causes first.
B0074 Description
B0074 engine trouble code is related to Timing Reference High Resolution Signal A Too Many Pulses.
Main Cause
The primary reason for B0074 OBD-II Engine Trouble Code is: Ambient Air Temperature Sensor Circuit Low.