Is your Chevrolet Express or GMC Savana van running rough, shifting erratically, or refusing to start? Are you battling a persistent check engine light with a host of confusing codes? The Powertrain Control Module (PCM), the central computer of your vehicle, is often the culprit behind these frustrating issues. This direct-fit replacement PCM, part number 16265035, is the definitive solution to restore your vehicle’s performance, reliability, and efficiency. We take the guesswork and hassle out of the repair by pre-programming the module to your van’s specific Vehicle Identification Number (VIN) before it ships. This ensures a seamless installation and immediate functionality, getting you back on the road or the job site with confidence.
From the Diagnostic Bay
I once had a 2001 Savana 2500 in the shop that was driving the owner crazy. It had a random misfire that would come and go, harsh shifting from 1st to 2nd, and terrible fuel economy. The owner had already replaced the spark plugs, wires, cap, rotor, and even a couple of sensors based on codes that popped up. Nothing worked. When we hooked up our high-level scanner, we noticed the data stream from the PCM was dropping out intermittently. The computer itself was failing internally. We installed a VIN-programmed PCM, performed the quick security relearn, and the van ran like it just rolled off the factory line. It’s a classic case of chasing symptoms when the root cause is the vehicle’s brain.
Is Your 1999-2002 Express 3500 PCM Failing?
A failing PCM can manifest in numerous ways, often mimicking other component failures. If you’re experiencing any of the following, it’s a strong indicator that your powertrain control module needs attention:
- ✔ Persistent Check Engine Light (CEL) that won’t clear or returns immediately.
- ✔ Multiple, unrelated diagnostic trouble codes (DTCs) being stored.
- ✔ Complete no-start condition where the engine cranks but won’t fire up.
- ✔ Intermittent stalling or cutting out while driving.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to communicate with a diagnostic scan tool.
- ✔ Engine performance issues like rough idling, hesitation, or misfires.
The Plug-and-Play Solution
Replacing a PCM used to mean a trip to the dealership for expensive diagnostics and programming. Our solution eliminates that step. By providing us with your VIN during checkout, you receive a module that is loaded with the latest GM-certified software specific to your vehicle’s original configuration. This process ensures all engine and transmission parameters are correct, restoring factory performance and addressing many common driveability issues that were fixed in later software updates. This isn’t just a replacement; it’s a restoration of your vehicle’s core operational logic.
This module is a direct replacement for several original equipment part numbers, including:
- 16265035
- 16263494
- 8162634940
- 218-11787
- 21811787
Wide-Ranging GM Compatibility
While this is a perfect fit for the 1999-2002 Express 3500 PCM, this versatile module was used across a vast lineup of GM’s most popular trucks, vans, and SUVs from that era. It is compatible with vehicles such as the Chevrolet Silverado, GMC Sierra, Tahoe, Yukon, Suburban, Astro, Safari, S10, Blazer, and more. Please verify your original part number or consult the detailed fitment list to confirm compatibility with your specific model and year.
Frequently Asked Questions
Do I need to get this module programmed?
No. We handle all the programming for you before shipping. Simply provide your vehicle’s VIN at checkout, and the module will arrive ready for installation with the latest GM software for your specific vehicle.
What is a VIN and why do you need it?
The VIN (Vehicle Identification Number) is a unique 17-digit code for your vehicle. It contains information about the make, model, year, engine, transmission, and other factory-installed options. We use the VIN to load the exact, correct software onto the PCM for your vehicle.
Is any special procedure required after I install the PCM?
Yes, on most of these GM vehicles, you will need to perform a security relearn procedure, sometimes called a CASE (Crankshaft Angle Sensor Error) relearn. This synchronizes the new PCM with your vehicle’s anti-theft system and crankshaft position sensor. This procedure is simple and can typically be done without special tools. Instructions are widely available online or in service manuals.
Will this fix my check engine light?
If the check engine light is caused by a faulty PCM or a software-related issue that is corrected by the latest GM updates, then yes, this will resolve it. However, if the light is on due to another failing component (like an oxygen sensor or catalytic converter), you will still need to repair that component.
Where is the PCM located on my Express Van?
On the 1999-2002 Express and Savana vans, the PCM is typically located in the engine compartment on the driver’s side, near the rear of the engine. On some other compatible vehicles like pickups, it may be on the driver’s side fender well or near the battery. Always disconnect the battery before attempting removal.