OBD Guide

C109D

Low Vacuum Condition Detected

C109D is an OBD-II diagnostic trouble code meaning: Low Vacuum Condition Detected. Common causes: vacuum leak in lines or connections, vacuum pump malfunction. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Reduced engine power
  • Unstable idling
  • Increased fuel consumption

Causes

  • Vacuum leak in lines or connections
  • Vacuum pump malfunction
  • Clogged vacuum lines
  • Damage to the vacuum brake booster

How to Fix

  1. Check the integrity of the vacuum lines
  2. Check connections for leaks
  3. Replace faulty vacuum pump
  4. Clear or replace clogged lines

Related codes

FAQ

What does the C109D code mean?

C109D is an OBD-II diagnostic trouble code that indicates: Low Vacuum Condition Detected

What causes a C109D error code?

The most common causes of C109D include: Vacuum leak in lines or connections; Vacuum pump malfunction; Clogged vacuum lines; Damage to the vacuum brake booster.

How do I fix a C109D diagnostic trouble code?

To fix C109D: Check the integrity of the vacuum lines. Check connections for leaks. Replace faulty vacuum pump. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with C109D?

Limited driving only, diagnose soon

How much does it cost to fix C109D?

The estimated repair cost for C109D is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat