Injector Cylinder 3 Circuit
The PACCAR-P1024 (PACCAR MX) diesel fault code means: Injector Cylinder 3 Circuit. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $400-$3,500
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Common Symptoms
- Power loss / derate
- Rough idle or misfire
- Hard starting or no-start
- Excessive smoke or fuel smell
- Check Engine Light illuminated
Probable Causes (Ranked by Likelihood)
- Failed injector or pressure sensor Likely
- Wiring harness damage at injector/sensor connector Likely
- Contaminated fuel or plugged filter Possible
- CP3 pump wear (high mileage) Possible
- Fuel rail pressure relief valve stuck Less Likely
Step-by-Step Diagnostic Procedure
Connect DAVIE4 and capture fuel rail pressure actual vs commanded during idle and snap-accel.
Inspect fuel filter(s) and water separator — replace if service interval exceeded.
Check injector wiring harness for chafing near valve cover and connector seal integrity.
Run injector balance / cut-out test with DAVIE4 to identify weak cylinder.
If CP3 pump is suspected, measure return-line flow and replace pump if excessive leakback.
Frequently Asked Questions
What does PACCAR MX code P1024 mean?
PACCAR MX code P1024 (Injector Cylinder 3 Circuit) is a serious-severity diagnostic trouble code set by the engine or aftertreatment control module on MX-11 and MX-13 engines in Kenworth and Peterbilt trucks. It indicates a fault in the fuel system that should be diagnosed with DAVIE4 or PACCAR ESA.
Can I drive a Kenworth or Peterbilt with PACCAR P1024?
Possibly — short distances may be OK, but ignoring the fault risks progressive damage, regen failure, or derate. Address promptly.
How much does it cost to fix PACCAR MX P1024?
Typical repair runs $400-$3,500. Sensor or wiring repairs are at the low end; injector, DEF pump, DPF, or EGR cooler jobs are at the high end. Dealer-level DAVIE4 software is often required for programming or calibration after parts replacement.
Sources
This page is built from documented references. Verify against your own service info before repair work.
P1024 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: