Restore Peak Performance to Your GM Vehicle
Is your GMC Safari, Chevy Express, or S10 pickup running rough, shifting erratically, or failing to start? These are classic signs of a failing Powertrain Control Module (PCM). As the central computer of your vehicle, the PCM is responsible for managing everything from fuel injection and ignition timing to transmission shift points and emissions controls. When it begins to fail, it can cause a cascade of frustrating and difficult-to-diagnose problems. This replacement PCM, part number 16263494, is the definitive solution to restore your vehicle’s reliability and drivability.
We take the guesswork out of the repair process. Unlike sourcing a part from a salvage yard, which comes with an unknown history and incorrect programming, this module is delivered to you fully programmed for your specific vehicle. Upon purchase, simply provide us with your Vehicle Identification Number (VIN), and our technicians will flash the unit with the latest GM-certified software updates. This ensures that your vehicle benefits from all factory improvements for fuel efficiency, emissions, and performance, making the installation process as straightforward as possible.
From the Diagnostic Bay
I remember a 2000 Chevy Astro van that came in with the most bizarre set of symptoms. The customer complained of intermittent stalling at stop lights, a check engine light that would come and go, and the transmission occasionally getting stuck in second gear. We checked everything – fuel pressure was good, sensors tested fine, and the wiring harness showed no obvious damage. After hours of chasing ghosts, we finally decided to monitor the PCM’s live data streams. We noticed the injector pulse width and ignition timing data would periodically drop out for a split second, just before a stall. It was a classic case of an internally failing processor on the PCM. We installed a VIN-programmed module just like this one, performed the security relearn, and the van ran like it just rolled off the factory floor. It’s a reminder that sometimes the ‘brain’ is the source of all the trouble.
Symptoms of a Failing 1999-2001 GMC Safari PCM
A faulty PCM can manifest in numerous ways. If you’re experiencing any of the following issues, your engine computer could be the culprit. Look out for:
- ✔ Unexplained Check Engine Light (CEL) illumination, often with communication error codes (U-codes).
- ✔ Engine stalling, sputtering, or misfiring, especially after the vehicle has warmed up.
- ✔ Harsh or erratic automatic transmission shifting, or getting stuck in one gear (limp mode).
- ✔ A complete no-start condition where the engine cranks but will not fire.
- ✔ Noticeable decrease in fuel economy.
- ✔ Failure to pass state emissions testing.
- ✔ Intermittent issues with other electronic components, like gauges or accessories.
Plug-and-Play Solution with VIN Programming
This isn’t just a part; it’s a complete service. The core of this offering is our professional VIN programming. By flashing the module to your vehicle’s exact specifications, we eliminate compatibility conflicts that can arise from using a generic or incorrectly matched computer. This ensures all onboard systems communicate correctly, from the anti-lock brakes to the instrument cluster. While the module is programmed for your vehicle, you will need to perform a simple security relearn procedure (often called the CASE relearn or Passlock relearn) after installation. This procedure syncs the new PCM with your vehicle’s anti-theft system and can typically be done in your driveway without special tools.
Frequently Asked Questions
Will this PCM be programmed for my specific vehicle?
Yes, absolutely. After you complete your purchase, you will need to provide us with your vehicle’s 17-digit VIN. Our technicians use this number to load the correct, updated GM software for your exact make, model, year, and engine configuration before we ship the part to you.
What is the difference between a PCM, ECM, and ECU?
The terms are often used interchangeably. ECM (Engine Control Module) typically controls only engine functions. ECU (Electronic Control Unit) is a generic term for any computer in a car. PCM (Powertrain Control Module) is the most accurate term for this part, as it controls both the engine and the automatic transmission functions in one integrated unit.
Is any special setup required after I install it?
While the module arrives programmed, you will likely need to perform a security relearn procedure. This syncs the new PCM to your vehicle’s anti-theft system. This procedure varies slightly by model but generally involves a sequence of turning the key in the ignition. Instructions are widely available online, or your mechanic can perform it quickly.
How can I be sure this part number is correct for my vehicle?
The best way is to check the part number on your original module. This PCM (16263494) is a direct replacement for several other part numbers, including 16265035 and 8162634940. You can also use the extensive fitment list on this page or contact us with your VIN to confirm compatibility before ordering.
Where is the PCM located on my vehicle?
The location varies. On many GM vans like the Safari, Astro, Express, and Savana, it’s in the engine compartment, often on the driver’s side near the battery or firewall. On S10/Blazer models, it’s typically on the passenger side firewall. For full-size pickups like the Silverado and Sierra, it’s usually under the battery tray on the driver’s side front fender.