Is Your 1999-2000 GM Truck Running Rough?
If your GMC Sierra, Chevy Silverado, or other compatible GM vehicle from this era is suffering from baffling engine problems, poor fuel economy, or erratic transmission behavior, the root cause is often a failing Powertrain Control Module (PCM). As the central computer of your vehicle, the PCM is responsible for managing everything from fuel injection and spark timing to transmission shift points and emissions controls. When it begins to fail, it can create a cascade of frustrating and difficult-to-diagnose issues, leaving you stranded or with an unreliable vehicle.
Don’t let a faulty computer dictate your truck’s performance. This is a direct-fit replacement PCM, part number 9354896, that arrives at your door fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We install the latest GM-certified software updates, ensuring optimal performance, fuel efficiency, and emissions compliance. This eliminates the need for expensive dealership programming and gets you back on the road with confidence.
From the Diagnostic Bay
We had a 2000 Sierra 1500 with the 5.3L V8 come into the shop with a complaint of intermittent stalling and a harsh 1-2 shift. The owner had already replaced the throttle position sensor and the mass airflow sensor with no improvement. The check engine light was on, but the codes were intermittent and pointed to a communication error. After confirming the wiring harness was intact, we suspected the PCM. We swapped in one of our VIN-programmed modules, performed the security relearn, and the truck immediately ran like new. The harsh shift was gone, the idle was stable, and the communication codes vanished. It’s a classic case of a failing computer mimicking other sensor failures, costing the owner time and money on unnecessary parts.
Common Symptoms of a Failing PCM
- ✔ Check Engine Light: Your Check Engine Light (CEL) is illuminated, often with internal processor fault codes like P0601, P0602, or P0606.
- ✔ Engine Performance Issues: You may experience random misfires, rough idling, stalling, hesitation during acceleration, or a significant loss of power.
- ✔ Poor Fuel Economy: A sudden and unexplained drop in your truck’s MPG is a strong indicator that the PCM is not managing the engine’s fuel delivery correctly.
- ✔ Transmission Problems: The PCM also controls the automatic transmission. Failure can lead to harsh shifting, delayed engagement, or getting stuck in one gear (limp mode).
- ✔ No-Start Condition: The engine may crank over but refuse to start. This can happen if the PCM fails to command the fuel injectors or ignition coils to fire.
- ✔ Failed Emissions Test: An inability to pass an emissions or smog test is often due to the PCM not functioning within its required parameters.
The Importance of a Programmed 1999-2000 Sierra 1500 PCM
Installing a generic, unprogrammed module from a salvage yard or a big-box store is not a viable solution for these vehicles. The PCM is the heart of a complex network of modules. It must be programmed with your truck’s specific VIN to communicate with the Body Control Module (BCM), anti-lock brake system (ABS), and instrument cluster. Our professional programming service ensures this critical communication happens flawlessly. We flash the module with the correct software for your engine, transmission, and emissions package, ensuring it works perfectly right out of the box after a simple security relearn procedure.
This module is a direct replacement for part numbers 19109040, 09354896, and 9354896 and fits a wide range of GM vehicles, including:
- 1999-2000 Chevrolet Silverado & GMC Sierra (1500/2500)
- 2000 Chevrolet Tahoe & Suburban
- 2000 GMC Yukon & Yukon XL
- 1999-2002 Chevrolet Camaro & Pontiac Firebird (5.7L)
- 1999-2000 Chevrolet Corvette
Restore the reliability and performance of your vehicle with a properly prepared and tested Powertrain Control Module. Simply provide your VIN after purchase, and we’ll handle the rest.
Frequently Asked Questions
Is this PCM difficult to install?
No, the physical installation is straightforward. On most trucks like the Sierra and Silverado, it’s located under the battery tray on the driver’s side. You simply disconnect the battery, remove the old module, install the new one, and reconnect the battery. The most critical step is performing the security relearn procedure afterward, which can typically be done without special tools.
What is the security relearn procedure?
This is a process that syncs the new PCM with your vehicle’s anti-theft system. A common method involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Your vehicle’s specific procedure may vary slightly, but it is a necessary step for the engine to start.
How do I provide my VIN?
After you complete your purchase, you will receive instructions on how to send us your 17-digit VIN. We cannot program or ship your module until we receive this information, so please provide it promptly to avoid delays.
Will this fix my specific problem?
This module will correct any issues directly caused by a faulty PCM. While the symptoms listed are common for PCM failure, they can also be caused by other issues. We always recommend a proper diagnosis by a qualified technician to confirm the PCM is the point of failure before ordering.
Is any other relearn needed besides the security relearn?
In some cases, a Crankshaft Position Sensor Variation Relearn (also known as CASE relearn) may be required to prevent a P1336 trouble code. This procedure requires a high-level scan tool and is often performed by a professional mechanic to ensure the most accurate ignition timing.