The Brain of Your GM Truck or Van
Your late 90s GM truck or van is a workhorse, but when its electronic brain—the Powertrain Control Module (PCM)—starts to fail, it can bring everything to a halt. The PCM is the central computer responsible for managing everything from fuel injection and ignition timing to transmission shifting and emissions controls. A faulty module can cause a host of frustrating and hard-to-diagnose problems that can sideline your vehicle. This replacement module is the definitive solution to restore your vehicle’s reliability and performance, acting as a direct-fit replacement for a wide range of GM trucks and vans, including the S10, Blazer, Express, Savana, and more.
From the Diagnostic Bay
We had a 1999 GMC Jimmy with the 4.3L come in with a complaint that was driving the owner crazy. It would randomly stall at stoplights, but only after it was fully warmed up. There were no consistent trouble codes. We checked fuel pressure, ignition components, and sensors—all tested fine. On a hunch, we monitored the PCM’s data stream and noticed the injector pulse width would suddenly drop to zero right before it stalled. The PCM’s internal driver for the fuel injectors was overheating and failing. Swapping in a correctly programmed PCM like this one solved the problem instantly. It’s often these internal, heat-related failures that don’t set a clear code but cause the most headaches.
Is Your GM Truck Showing Signs of a Bad PCM?
A failing PCM can manifest in numerous ways, often mimicking other component failures. If you’re experiencing any of the following symptoms, a faulty computer could be the root cause:
- ✔ Check Engine Light: An illuminated or flashing check engine light with codes related to module communication (U-codes), sensor circuits (P-codes), or internal processor faults.
- ✔ No-Start or Intermittent Stalling: The engine cranks but won’t start, or it stalls unexpectedly while driving or idling, often without warning.
- ✔ Poor Engine Performance: A noticeable loss of power, rough idling, hesitation during acceleration, engine misfires, or a significant drop in fuel economy.
- ✔ Harsh or Failed Transmission Shifting: The transmission may shift erratically, slam into gear, get stuck in one gear (limp mode), or fail to shift at all.
- ✔ Communication Errors: A professional scan tool is unable to communicate with the PCM, indicating a critical internal failure.
- ✔ Inconsistent Instrument Cluster Behavior: Gauges may behave erratically, drop to zero, or not work at all.
The Plug-and-Play Solution
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take the guesswork out of the repair by programming this 1998-2000 S10 PCM specifically to your vehicle’s Vehicle Identification Number (VIN). This process ensures that the module has the correct software and calibrations for your truck’s specific engine, transmission, and options. Furthermore, we load the latest available software updates from General Motors, which can resolve underlying drivability issues you may not have even known were software-related. This VIN-specific programming makes the installation process as simple as possible.
Installation and Setup
Installing your new 1998-2000 S10 PCM is a straightforward process. After disconnecting the battery, simply locate your old module (locations vary by model, see fitment list), unplug the electrical connectors, and unbolt it. Bolt the new module in its place, reconnect the connectors, and reconnect the battery. Because this module is pre-programmed to your VIN, there is no need for a trip to the dealership for expensive programming. However, on many of these GM vehicles, you will need to perform a simple security relearn procedure (often called the Passlock or VATS relearn) to allow the vehicle to start. This procedure can be done in your driveway and typically involves turning the key to the ‘ON’ position for 10-15 minutes, three times in a row. Don’t let a failing computer sideline your reliable GM truck or van. By providing us with your VIN at checkout, you receive a module that is tested, prepared, and ready for installation, getting you back on the road quickly and confidently.
Frequently Asked Questions
What exactly does the Powertrain Control Module (PCM) do?
The PCM is your vehicle’s main computer. It controls the engine’s fuel delivery, spark timing, and emissions systems, as well as the transmission’s shifting patterns, to ensure optimal performance, fuel efficiency, and low emissions.
Do I need to get this module programmed at a dealership?
No. We handle all the programming for you before we ship the part. Simply provide your vehicle’s VIN during or after checkout, and it will arrive ready to install.
What is the security relearn procedure you mentioned?
This is a simple process that syncs the new PCM with your vehicle’s anti-theft system. It typically involves a sequence of key cycles and waiting periods that you can perform yourself without any special tools. Instructions are widely available online for your specific model.
How do I find and provide my VIN?
Your 17-digit VIN can be found on your vehicle’s registration, insurance card, or on a plate on the driver’s side dashboard visible through the windshield. Please provide this number to us after you complete your purchase so we can program your module.
My truck has part number 16263494. Will this module work?
Yes. This module is a direct replacement for several part numbers, including 16263494, 16265035, and others listed. As long as your vehicle is on the compatibility list, this module will function correctly once programmed to your VIN.