Is Your GM Truck or Van Running Rough?
If your late 90s or early 2000s Chevrolet or GMC vehicle is suffering from erratic engine behavior, poor fuel economy, or a persistent Check Engine Light, a failing Powertrain Control Module (PCM) could be the culprit. As the central computer for your engine and transmission, the PCM is responsible for managing everything from fuel injection and spark timing to transmission shift points. When it fails, it can cause a cascade of frustrating and difficult-to-diagnose issues. This replacement module, part number 8162634940, is the definitive solution to restore your vehicle’s performance and reliability.
From the Diagnostic Bay
We once had a 1999 Chevy Silverado 1500 in the shop with a classic complaint: stalling at stoplights and harsh, unpredictable shifting. The owner had already replaced the throttle position sensor and the mass airflow sensor based on some generic trouble codes, but the problem persisted. After confirming all sensor inputs were good, we hooked up our diagnostic scanner and monitored the live data from the PCM. We saw injector pulse widths dropping out intermittently, a dead giveaway of a failing driver circuit inside the module. We installed a VIN-programmed PCM, performed the security relearn, and the truck ran like it just rolled off the assembly line. It’s a reminder that sometimes, the problem lies with the brain, not the sensors.
Symptoms of a Failing Powertrain Control Module
- ✔ Persistent Check Engine Light (CEL) with various trouble codes
- ✔ Engine stalling, stumbling, or misfiring
- ✔ Harsh or erratic automatic transmission shifting
- ✔ A complete no-start condition where the engine cranks but won’t fire
- ✔ Noticeable decrease in fuel efficiency
- ✔ Failure to pass emissions testing
- ✔ Communication errors with diagnostic scan tools
The Right Solution: A VIN-Programmed 1998-2000 Blazer PCM
Don’t settle for a generic, unprogrammed module from a salvage yard that will cause more headaches. We take the guesswork out of the repair. This unit is a direct replacement for a wide range of GM vehicles and is professionally programmed to your vehicle’s specific Vehicle Identification Number (VIN) before it ships. This ensures that all factory software, including the latest GM updates, is loaded for optimal performance and compatibility. Simply provide us with your VIN after purchase, and we’ll handle the complex programming, making your installation process as straightforward as possible.
This module is a direct replacement for part numbers 16263494, 16265035, 8162634940, 218-11787, and 21811787. After installation, you may need to perform a simple security relearn procedure (often called a Passlock or CASE relearn) to sync the new module with your vehicle’s anti-theft system. This can typically be done without special tools and instructions are widely available.
Frequently Asked Questions
What does the PCM do on my truck?
The Powertrain Control Module, or PCM, is the main computer that controls your vehicle’s engine and transmission. It reads data from dozens of sensors to manage fuel delivery, ignition timing, emissions systems, and automatic transmission shifting to ensure optimal performance, efficiency, and low emissions.
Is this module ready to install out of the box?
Yes, this module is programmed to your vehicle’s VIN before we ship it. This means it comes loaded with the correct software for your specific make, model, and engine. However, you will likely need to perform a security relearn procedure after installation for the vehicle to start and run correctly.
Where do I find my vehicle’s VIN?
Your 17-digit Vehicle Identification Number (VIN) can be found on a metal tag on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM directly controls the transmission’s electronic solenoids to manage shifting. If the PCM’s internal drivers are failing, it can cause harsh shifts, delayed engagement, or slipping. If your issue is caused by a faulty module, this part will resolve it.
What is a security relearn procedure?
It’s a simple process that syncs the new PCM with your vehicle’s anti-theft system (like GM’s Passlock). It usually involves a sequence of turning the key on and off for set periods. This procedure is necessary to allow the engine to start after the new module is installed.