Restore Peak Performance to Your GM Truck or Van
Is your GMC Envoy, Chevy Blazer, S10, or Silverado running rough, stalling, or displaying a persistent Check Engine Light? These are common indicators of a failing Powertrain Control Module (PCM), the central computer responsible for managing your vehicle’s engine and transmission. This replacement PCM, part number 16263494, is the definitive solution to restore your vehicle’s original performance, fuel efficiency, and reliability. It’s not just a part; it’s the brain of your vehicle, brought back to perfect working order.
This module arrives at your door fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We install the latest GM-certified software updates, ensuring that any factory bugs are corrected and performance is optimized. This critical programming step means you get a plug-and-play component that eliminates the need for an expensive trip to the dealership for flashing. Simply provide your VIN after purchase, and we handle the rest.
From the Diagnostic Bay
We had a 1999 Chevy Blazer in the shop that was driving the owner crazy. It had a random misfire (P0300) that no one could solve. The owner had already replaced the spark plugs, wires, distributor cap, rotor, and even the fuel spider injector assembly. The misfire would disappear for a day and then come back. After hooking up our professional scan tool and monitoring live data, we noticed the fuel trim values were erratic and injector pulse width commands were inconsistent, but only intermittently. This pointed away from a mechanical issue and toward the command center itself. We installed a pre-programmed PCM, performed the required security relearn, and the truck ran perfectly. The original PCM’s internal driver for an injector was failing under certain temperature conditions, a problem that parts-swapping couldn’t solve. This highlights the importance of correctly diagnosing the root cause, which is often the module itself.
Diagnosing a Faulty 1998-2000 Envoy PCM
A failing PCM can manifest in numerous ways, often mimicking other sensor or component failures. If you’ve been chasing ghosts in your electrical or fuel system, it might be time to consider the module. This unit is a direct replacement for a wide range of popular GM trucks, SUVs, and vans from the late 90s and early 2000s, including the Chevrolet Express, GMC Savana, and Isuzu Hombre equipped with the 4.3L, 5.0L, or 5.7L engines.
Common Symptoms of PCM Failure
- ✔ Check Engine Light: The light may be on with various communication error codes (U-codes) or false sensor codes.
- ✔ Engine Stalling: The engine may stall unexpectedly while driving or at idle.
- ✔ No-Start Condition: The engine cranks but refuses to start, despite having spark and fuel pressure.
- ✔ Poor Fuel Economy: A sudden and unexplained drop in MPG can be caused by incorrect fuel and air mixture calculations.
- ✔ Erratic Shifting: The transmission may shift harshly, late, or not at all, as the PCM also controls transmission functions.
- ✔ Failed Emissions Test: The vehicle may fail a smog test due to incorrect engine parameters.
- ✔ Intermittent Issues: Problems that appear and disappear with changes in temperature or driving time often point to failing electronics within the PCM.
A Simple, Reliable Solution
Replacing your faulty computer is a straightforward process. This PCM is built to meet or exceed original equipment specifications. Once you install the module, you may need to perform a simple security relearn procedure (often called a CASE relearn or anti-theft relearn), which can typically be done without special tools and instructions are readily available online. By providing us with your VIN, you ensure that this 1998-2000 Envoy PCM is perfectly matched to your vehicle’s specific configuration, including engine size, transmission type, and emissions equipment.
Frequently Asked Questions
Do I need to do any programming myself?
No. This module comes fully programmed to your vehicle’s VIN with the latest GM software updates. It is ready to be installed upon arrival. You will just need to provide us with your VIN after you complete your purchase.
What is a security relearn procedure?
Many GM vehicles of this era have a passive anti-theft system (Passlock/VATS) that links the PCM to your key and ignition. After installing a new PCM, you may need to perform a simple key-cycling procedure to allow the new module to recognize your vehicle’s key. This usually takes about 30 minutes and does not require a scan tool.
Is this compatible with other part numbers?
Yes, this PCM is a direct replacement for several part numbers, including 16265035, 8162634940, and 218-11787. If your original module has one of these numbers, this part will be a perfect fit.
Where is the PCM located on my vehicle?
The location varies by model. On many trucks like the Silverado and Sierra, it’s in the engine bay on the driver’s side, often under the battery tray. On vans like the Express and Savana, it’s typically in the LH rear of the engine compartment. For S10/Blazer/Envoy models, it is often found on the RH front of the engine compartment. Always disconnect the battery before removal and installation.
What information do you need from me?
After you place your order, we will need the 17-digit Vehicle Identification Number (VIN) from your vehicle. This can be found on your dashboard (visible through the windshield), on your driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.