Is Your GM Truck or Van Running Rough?
If you’re experiencing baffling issues like a persistent check engine light, erratic engine behavior, poor fuel economy, or harsh transmission shifting in your Chevrolet Express, GMC Savana, or other compatible GM vehicle, the culprit is often the Powertrain Control Module (PCM). As the central computer for your engine and transmission, a failing PCM can cause a cascade of problems that are frustrating and difficult to diagnose. Don’t let a faulty module keep you off the road. This replacement PCM is the reliable, straightforward solution to restore your vehicle’s performance and dependability.
From the Diagnostic Bay
We had a 2001 GMC Savana 2500 work van come into the shop with an intermittent no-start condition that was driving the owner crazy. It would run fine for days, then refuse to start for an hour. There were no consistent trouble codes, just a generic communication error that would pop up occasionally. We checked grounds, wiring, and sensors for two days. Finally, we hooked up a scope to the PCM’s main power and data lines and saw the voltage drop out unpredictably. We installed one of these VIN-programmed PCMs, performed the security relearn, and the van fired up instantly. The owner called a month later to say it hadn’t missed a beat since. A faulty computer can mimic a dozen other problems.
Symptoms of a Failing Powertrain Control Module
- ✔ Persistent Check Engine Light (CEL) illumination, often with U-series (communication) codes.
- ✔ Unexplained engine stalling, stumbling, or rough idling.
- ✔ A noticeable decrease in fuel efficiency.
- ✔ Harsh, erratic, or delayed automatic transmission shifts.
- ✔ Complete no-start or intermittent starting problems where the engine cranks but won’t fire.
- ✔ Failure to pass state emissions testing due to readiness monitor issues.
- ✔ Inaccurate or non-functional dashboard gauges.
The Simple Solution: A VIN-Programmed 1999-2002 Express 3500 PCM
Replacing the PCM on these older GM vehicles used to mean a trip to the dealership for expensive programming. We’ve eliminated that step. When you order this module, we use the Vehicle Identification Number (VIN) you provide to flash it with the latest, most stable GM-approved software specifically for your vehicle’s configuration. This ensures that all parameters for the engine, transmission, fuel system, and emissions components are perfectly matched.
This module is a direct replacement for multiple original part numbers, including 16263494, 16265035, and 8162634940. Installation is straightforward: disconnect the battery, unbolt the old module, and install the new one. After installation, you will need to perform a simple security relearn procedure (often called the Passlock or VATS relearn), which pairs the new module to your vehicle’s anti-theft system. This procedure typically does not require special tools and can be found in owner’s manuals or online resources.
Frequently Asked Questions
Do I need to have this PCM programmed?
No. We handle all the programming for you before shipment. Simply provide us with your vehicle’s 17-digit VIN during or after checkout, and we will flash the module with the correct GM software for your exact vehicle.
Is this a simple plug-and-play installation?
It is a direct physical replacement, but it is not entirely plug-and-play. After installing the module, you must perform a security relearn procedure to sync the new PCM with your vehicle’s anti-theft system. This process usually involves a sequence of key turns and waiting periods and does not require a mechanic’s scan tool.
How do I provide my VIN?
You can add your VIN to the notes section during checkout. If you forget, don’t worry—we will contact you via email after your purchase to request the information needed for programming.
Will this part fix my check engine light?
If the check engine light and associated symptoms are caused by a faulty PCM, this part will resolve the issue. However, it’s crucial to ensure your vehicle has been properly diagnosed, as other failing sensors or wiring problems can cause similar symptoms. This module will fix problems originating from the computer itself.
What part numbers is this compatible with?
This module is a direct replacement for several service numbers, including 16263494, 16265035, 8162634940, 218-11787, and 21811787. Please check our extensive fitment list to confirm compatibility with your specific make and model.