P0341 on 2014-2018 GMC Sierra 2500: Camshaft Sensor Range/Performance Issues

What's Unique About the 2014-2018 Gmc SIERRA 2500

On this generation of Sierra and its platform mates (Silverado, Tahoe, Yukon), P0341 is not always a straightforward sensor failure. GM has issued Technical Service Bulletins (TSBs) that point to specific wiring harness vulnerabilities. TSB PIP5724 details how the wiring jumper harness can get pinched between the X154 connector bracket and the front engine cover on the lower left side of the engine. Additionally, TSB PIP5335C points to potential corrosion within that same X154 connector, which is located near the vacuum pump and is susceptible to moisture. These known issues make a thorough wiring inspection more critical on these trucks than on many other vehicles where P0341 is more commonly just a bad sensor.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light is on
• Engine is hard to start or cranks but won't start
• Engine stalls, sometimes at low speeds or during turns
• Rough idling or surging at low speeds
• Reduced engine power and poor acceleration, possible 'limp mode'
• Increased fuel consumption
• Hesitation or stumbling during acceleration

Most Likely Causes

1. Wiring Harness or Connector Issue 🔴 High Probability TSB #PIP5724 specifically calls out a pinched wiring harness near the front engine cover by the X154 connector bracket. TSB #PIP5335C notes that diagnostics may not isolate the cause and points to corrosion in the X154 connector. Forum users and videos confirm finding chafed or exposed wires in the harness that runs along the front of the engine, which can ground out and cause an intermittent signal loss, especially in moist conditions.
   How to confirm: Visually inspect the wiring harness leading to the camshaft position sensor for any signs of chafing, pinching, melting, or corrosion, especially near the front of the engine by the power steering pump and accessory brackets. Pay close attention to the X154 connector. Wiggle the connector and wiring with the engine running to see if it affects engine performance or the sensor signal on a scan tool.
   Typical fix: Repair the damaged section of the wire with solder and heat shrink, or replace the connector pigtail. Apply dielectric grease to protect the connection from moisture. Reroute or secure the harness to prevent future damage.
   Est. part cost: $15-$50
2. Faulty Camshaft Position (CMP) Sensor 🔴 High Probability → Shop Engine Camshaft Position Sensor Sensors are electronic components that can fail over time due to extreme heat cycles and vibration in the engine bay. While common, it's often misdiagnosed when the actual problem is wiring. There are many forum reports of aftermarket sensors failing prematurely, leading owners to recommend using only OEM ACDelco parts.
   How to confirm: Test the sensor's signal with an oscilloscope for a clean square wave pattern. A diagnostic scan tool can also monitor the live data from the sensor to check for dropouts. This should be done after confirming the wiring is intact.
   Typical fix: Replace the camshaft position sensor. It is strongly recommended to use a genuine OEM ACDelco part (such as part number 12680635 for the 6.2L V8) to avoid premature failure associated with some aftermarket sensors.
   Est. part cost: $25-$80
3. Stretched Timing Chain or Timing Issue ⚪ Low Probability → Shop Engine Timing Chain On higher mileage engines (typically over 100,000 miles), the timing chain can stretch, causing the camshaft and crankshaft signals to fall out of sync, which can trigger a P0341 code. This is a known, though less frequent, issue on GM V8 engines.
   How to confirm: This is an advanced diagnosis. An oscilloscope is used to compare the camshaft and crankshaft sensor patterns to a known-good waveform. If they are out of sync, a mechanical timing issue is likely. This is often accompanied by other codes like P0016, which specifically indicates a correlation error.
   Typical fix: Replace the timing chain, tensioners, and guides. This is a labor-intensive and expensive job.
   Est. part cost: $300-$800

Rare But Worth Checking

• Damaged Reluctor Wheel: The reluctor wheel on the camshaft, which the sensor reads, can be damaged, come loose, or have debris on it, causing an erratic signal. This is uncommon but has been noted as a possibility, especially if other engine work was recently performed.
• Failing Engine Control Module (ECM): A faulty ECM is a rare cause. All other possibilities should be exhaustively ruled out before considering ECM replacement, which requires programming.

Diagnosis Steps

1. Scan the ECM for P0341 and any other stored codes. Note the freeze-frame data.
2. Perform a thorough visual inspection of the camshaft position sensor, its connector, and the entire wiring harness. Per TSBs PIP5724 and PIP5335C, pay extremely close attention to the harness near the X154 connector bracket on the lower left front of the engine for signs of pinching, chafing, or corrosion.
3. Inspect the harness for damage where it runs near the A/C compressor and power steering pump. Look for brittle or crumbling wire loom.
4. If wiring appears suspect, gently wiggle the harness and connector while the engine is running (or while monitoring sensor data on a scan tool) to see if the fault can be duplicated.
5. If wiring is confirmed good, test the sensor itself. Check for stable 5V reference, good ground, and a clean signal wire at the connector. The best method is using an oscilloscope to view the square wave signal while the engine is running. A glitchy or absent signal indicates a bad sensor.
🎬 Watch: Two quick DIY methods to fix the P0341 code.
6. If the sensor and wiring are good, the final step is to investigate potential mechanical timing issues (e.g., stretched timing chain), especially if codes like P0016 are present.

Parts You'll Likely Need

• Camshaft Position Sensor (OEM #ACDelco 12680635 (example for 6.2L, verify for specific engine)) — This is the most frequently replaced component to resolve a P0341 code, after ruling out wiring issues. Using an OEM part is highly recommended.
  Trusted brands: ACDelco (OEM), Delphi, NGK/NTK
  OEM price range: $40-$80
  Aftermarket price range: $25-$60
• Camshaft Position Sensor Connector Pigtail (OEM #ACDelco PT2628 (Verify application)) — If the connector or its immediate wiring is corroded, melted, or damaged from chafing, replacing the pigtail is the correct repair, as highlighted by the known TSBs.
  Trusted brands: ACDelco, Dorman
  OEM price range: $25-$50
  Aftermarket price range: $15-$30

Related Codes That Often Appear With This One

• P0340 — P0340 indicates a general circuit malfunction (signal lost >2 sec), while P0341 points to a performance/range problem (signal lost <2 sec). Since they relate to the same sensor and circuit, they frequently appear together.
• P0335 / P0336 — These codes relate to the Crankshaft Position Sensor. The ECM compares signals from both the cam and crank sensors, so a fault in one can sometimes trigger codes for the other. TSB PIP5724 lists these codes as also being potential results of the same pinched wiring harness issue.
• P0016 — This code indicates a Crankshaft/Camshaft Correlation error. Seeing P0341 and P0016 together strongly suggests a mechanical timing problem, like a stretched timing chain, rather than an electrical fault.

Technical Service Bulletins (TSBs) & Recalls

• PIP5335C: Mentions that with DTCs P0340 and P0341, normal diagnostics may not isolate the root cause, pointing towards a more complex or hidden issue like corrosion in a specific connector.

Platform-Specific Known Issues

• TSB #PIP5724: Warns of a possible pinched wiring jumper harness between the X154 connector bracket and the front engine cover on the lower left side of the engine, causing P0341 and a host of other codes.
• TSB #PIP5335C: Specifically for 2014-2016 models, this bulletin suggests inspecting for corrosion in connector X154 (located on the front cover near the vacuum pump) if normal diagnostics fail to find the cause of P0340/P0341.
• Owner Experience: A user on PerformanceTrucks.net forums described chasing P0340/P0341 after a cam swap, which ended up being a bad sensor, highlighting the frustration of diagnosis even for experienced individuals.

Mechanic-Grade Diagnostic Values

• Camshaft Position Sensor 5V Reference Voltage (at sensor connector) — expected: 4.8V - 5.2V with Key On, Engine Off (KOEO). Failure: Voltage below 4.8V or absent suggests a wiring issue (short/open), a problem with another sensor on the same 5V reference circuit, or a faulty ECM.
• Camshaft Position Sensor Ground Circuit Resistance — expected: Near 0 Ohms of resistance between the ground pin at the connector and a known good chassis/engine ground.. Failure: High resistance (more than a few ohms) indicates a corroded or broken ground wire, which can cause an unstable sensor signal.
• Camshaft Position Sensor Signal Wire (with oscilloscope) — expected: A clean digital square wave pattern that toggles between approximately 0V and 5V as the engine is running or cranked.. Failure: A missing waveform, a waveform with glitches, rounded-off edges, or incorrect frequency indicates a failing sensor or a mechanical issue with the reluctor wheel.

Scan Tool Commands That Help

• GDS2 / Professional Scan Tool: Crankshaft Position Variation Learn (also known as CASE Learn or Cam/Crank Relearn) — This procedure should be performed after replacing the camshaft position sensor, crankshaft position sensor, or ECM. It allows the ECM to learn the minor variations in the new sensor and the reluctor wheel to ensure accurate timing and misfire detection. Failure to perform this can sometimes cause the P0341 code to persist.
• Professional Scan Tool: ECM Adaptation Resets — After a repair is completed, resetting learned fuel trims and other adaptive values can clear old data that might cause the ECM to run incorrectly, helping to confirm if the fix was successful.

Wiring & Ground Locations

• X154 / X159 — Located on the front engine cover, near the vacuum pump. TSB PIP5335C notes X159 is a possibility for 2015 models specifically.. This connector is a known weak point for corrosion due to its location, which can directly cause intermittent signal loss for the camshaft position sensor, triggering P0340/P0341.
• G103 / G104 — G103 is typically on the front of the passenger-side cylinder head. G104 is on the rear of the driver-side cylinder head.. These are primary engine block grounds. A loose or corroded connection at these points can create electrical noise and unstable sensor readings throughout the engine management system, potentially causing a P0341.
• G218 — Located under the driver's side dashboard, often behind the kick panel or A-pillar trim.. This is an interior body ground. On some GM trucks, sound-deadening foam insulation can get pinched under the ground nut, causing a poor connection. This can lead to a wide range of bizarre electrical issues, and while less direct, could contribute to ECM or sensor circuit problems.
• CMP Sensor Connector Pins — At the camshaft position sensor itself.. Testing requires identifying the three pins: 5-Volt Reference, Low Reference (Ground), and Signal. A wiring diagram for the specific engine is crucial as wire colors can vary.

Real Owner Repair Stories

• YouTube channel 'Cspec Curt' (Chevrolet Silverado (K2XX Platform sibling)) — Intermittent P0341 code, sometimes P0340 and P0336. Shuttering and loss of power, especially in damp or moist weather.
  ❌ Tried (didn't work) Replacing the camshaft position sensor did not fix the issue.
  ✅ What actually fixed it The owner found a chafed blue wire with exposed copper in the wiring harness that runs along the front of the engine. The crumbling factory wire loom had allowed the wire to rub and intermittently ground out. Repairing the damaged section of the wire resolved the codes and symptoms.

When the Usual Fixes Don't Work

• A common but often incorrect assumption is that P0341 is fixed by replacing the camshaft position sensor. While the sensor can fail, a significant number of owners and technicians find the code returns. The counter-evidence points to the high probability of a wiring harness issue, as documented in GM's own Technical Service Bulletins. In one documented case, an owner replaced the sensor, but the problem persisted until a chafed wire in the engine harness—which only caused a fault in damp weather—was found and repaired. This highlights that for the 2014-2018 Sierra 2500, a wiring inspection is not just a suggestion but a critical first diagnostic step, even before testing the sensor itself.

Model Year Variations Within This Range

• 2015: TSB #PIP5335C notes that when checking for corrosion as a cause for P0340/P0341, the relevant connector could be X154 or X159 on 2015 models, whereas other years primarily reference X154.