C1085 Engine Trouble Code
What is C1085?
With C1085, you may drive for several weeks with a malfunctioning MAF sensor, but expect decreased fuel economy and eventual stalling. Shop replacement costs $240–$400 depending on vehicle. The labour is straightforward, with most cost from the part itself.
Code Information
| Code Type: | OBD-II Chassis (C) Trouble Code |
| System: | Chassis |
| Code: | C1085 |
C1085 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
C1085 Code Structure
Understanding what each digit means in the C1085 chassis trouble code:
| C | 1 | 0 | 8 | 5 |
|---|---|---|---|---|
| Chassis Code | Fuel And Air Metering | Ambient Air Temperature Sensor Circuit Low | Ignition/Distributor Engine Speed Input Circuit Malfunction | Crankshaft Position Sensor B Circuit Malfunction |
How to Fix C1085
Diagnostic Steps:
Poor running symptoms align with MAP sensor malfunction. In some cases, a faulty MAP sensor will not trigger a code. The issue may represent separate wiring concerns requiring individual diagnosis.
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:
C1085 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.
C1085 Description
C1085 engine trouble code is related to Crankshaft Position Sensor B Circuit Malfunction.
Main Cause
The primary reason for C1085 OBD-II Engine Trouble Code is: Ambient Air Temperature Sensor Circuit Low.