EGR Valve Actuator - Calibration Required
The CAT-CID1079-FMI13 (Caterpillar) diesel fault code means: EGR Valve Actuator - Calibration Required. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- advanced
- Estimated cost
- $600-$5500
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View pilot availability →What Are the Symptoms of CAT-CID1079-FMI13?
- Check Engine Light
- Black smoke, especially under load
- Low power or derate
- Poor fuel economy
- Rough idle / misfire
- Coolant loss (if EGR cooler is failing)
What Causes CAT-CID1079-FMI13? (Most Likely First)
- EGR valve seized or carboned up Very Likely
- EGR actuator motor or position feedback failed Likely
- Wiring or connector issue at EGR valve Likely
- EGR cooler cracked/leaking coolant (common ACERT failure) Possible
- EGR venturi tube cracked Possible
- Calibration lost after battery or ECM power-down Possible
Can I Still Drive with CAT-CID1079-FMI13?
Short distances only. CAT-CID1079-FMI13 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does CAT CID1079-FMI13 mean?
CAT code CID1079-FMI13 (EGR Valve Actuator - Calibration Required) is a moderate-severity EGR fault on C13 and C15 ACERT engines. EGR actuator learn/calibration required after service. ACERT engines are notorious for EGR cooler failures that leak coolant into the intake.
Is the EGR cooler failing a common issue on ACERT engines?
Yes. The C13 and C15 ACERT EGR cooler is a known weak spot. Symptoms include coolant loss with no visible external leak, white smoke at startup, and oil contamination. Delete / bypass kits are popular in some markets but may be illegal on-road in many jurisdictions.
How much to fix CAT CID1079-FMI13?
EGR valve cleaning is $300-$500 labor. EGR valve replacement is $800-$1500. EGR cooler replacement is $2500-$5500 depending on engine access. EGR venturi tube is $600-$1200.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose CAT-CID1079-FMI13?
Read active and logged faults with CAT ET; note EGR valve commanded vs actual position.
Command EGR valve through its range in CAT ET; watch position feedback.
Remove EGR valve and inspect for carbon loading; clean or replace as required.
Pressure-test EGR cooler for coolant-side leaks (very common ACERT failure).
Inspect EGR venturi tube for cracks (tube runs hot and is prone to fatigue).
Perform EGR re-learn in CAT ET after any replacement.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J1939-73Application Layer: Diagnostics (defines the SPN/FMI fault-identifier framework)
Which Vehicles Commonly Get CAT-CID1079-FMI13?
- Kenworth T800 with CAT C15
- Kenworth W900 with CAT C15
- Kenworth T2000 with CAT C15
- Peterbilt 379 with CAT C15
- Peterbilt 389 with CAT C15
- Peterbilt 386 with CAT C15
- Peterbilt 387 with CAT C15
- Freightliner Classic XL with CAT C15
- International 9200i with CAT C15
- International 9400i with CAT C15
- Western Star 4900 with CAT C15
- Western Star 5900 with CAT C15
- Kenworth T800 with CAT C13
- Kenworth T660 with CAT C13
- Peterbilt 386 with CAT C13
- Peterbilt 387 with CAT C13
- Freightliner Columbia with CAT C13
- International 9200i with CAT C13
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