Restore Your Van’s Reliability and Performance
Is your GMC Savana or Chevy Express van giving you headaches? Unexplained stalling, a persistent Check Engine Light, or erratic transmission shifting can often be traced back to a single, critical component: the Powertrain Control Module (PCM). As a technician with over two decades of experience under the hood, I’ve seen firsthand how a failing PCM can throw a whole vehicle out of sync. This isn’t just a part; it’s the brain of your engine, and when it falters, everything suffers.
This isn’t a generic, off-the-shelf computer. We take the guesswork and dealer-level expense out of the equation. When you order, you provide us with your vehicle’s VIN. We then flash this module with the latest, most stable GM software specific to your exact vehicle configuration. This ensures that when it arrives, it’s ready to restore your engine’s fuel delivery, ignition timing, and transmission control to factory specifications. This is the definitive fix for many frustrating and hard-to-diagnose issues.
A Technician’s Notebook: The Ghost in the Machine
I once had a 2001 Express 2500 work van in my bay that was driving the owner crazy. It had random misfire codes, a harsh 1-2 shift, and would occasionally stall at red lights. The owner had already replaced spark plugs, wires, and even a throttle position sensor with no luck. The symptoms were inconsistent. After hooking up my scan tool and seeing no clear sensor failure, experience pointed me to the PCM. A failing computer can send out bad signals, making good sensors look faulty. We installed a VIN-programmed PCM, and it was like a new van. All the ghost codes vanished, the shifting smoothed out, and the stalling stopped. It’s a classic case of the central command unit failing, and a reminder that starting with the brain is often the right move.
Is Your GM Vehicle Showing These Symptoms?
- âś” Check Engine Light is on with codes like P0601, P0602, or P0606 (Internal Control Module Memory Check Sum Error).
- âś” The engine cranks but refuses to start.
- âś” Unexplained drops in fuel economy.
- âś” Harsh or erratic automatic transmission shifting.
- âś” The vehicle stalls intermittently, especially when coming to a stop.
- âś” Failure to pass an emissions test.
- âś” Communication errors with your scan tool.
Your Straightforward Installation Guide
Replacing the PCM in these GM vans and trucks is a job most DIYers can handle in under an hour. Our pre-programming service eliminates the need for expensive dealer tools.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- Locate the PCM: On most Savana and Express vans, the PCM is located in the engine compartment on the left-hand (driver’s) side, often near the battery or firewall. On some pickups and SUVs, its location may vary slightly (e.g., under the battery tray).
- Disconnect Connectors: Carefully unlatch and remove the electrical wiring harnesses from the old module. These connectors have locking tabs that need to be released before pulling.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware as you will reuse it.
- Install the New PCM: Mount your new, VIN-programmed PCM onto the bracket and securely tighten the bolts.
- Reconnect Everything: Plug the wiring harnesses firmly into the new module until they click and lock into place. Reconnect your negative battery terminal.
- Perform Security Relearn: Your vehicle may require a simple security relearn procedure to recognize the new PCM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes. Consult your owner’s manual for the specific steps for your model.
Verified Vehicle Compatibility
This Powertrain Control Module is a direct replacement for a wide range of popular GM trucks, vans, and SUVs from the late 1990s and early 2000s. It is compatible with part numbers 16263494, 16265035, and 8162634940. While this listing is centered on the 1999-2002 Savana 2500 PCM, it also fits models like the Chevy Silverado, GMC Sierra, Tahoe, Yukon, Astro, Safari, S10/Sonoma, and more. Please review the detailed fitment list to confirm this is the correct part for your specific year, make, and model.
Frequently Asked Questions
Do I need to do any programming myself?
No. We handle all the programming before we ship the part. Simply provide your vehicle’s 17-digit VIN during checkout, and we will flash the module with the correct GM software and updates for your vehicle.
What is the security relearn procedure?
This is a simple, anti-theft handshake between the new PCM and your vehicle. It usually involves leaving the key in the ‘ON’ position for about 10-15 minutes. This allows the vehicle’s Body Control Module to synchronize with the new PCM. No special tools are needed.
Will this fix my transmission problems?
In many cases, yes. The PCM controls transmission line pressure and shift points. If your module is failing, it can cause hard shifts, delayed shifting, or slipping. A new, correctly programmed PCM often resolves these communication-based transmission issues.
Is this a guaranteed fix for my check engine light?
This module will resolve any issues and codes directly caused by a failing PCM (like code P0601). However, if your Check Engine Light is on due to a separate faulty sensor (like an O2 sensor or MAP sensor), that part will still need to be addressed. A proper diagnosis is always recommended.
Where do I find my VIN?
Your Vehicle Identification Number (VIN) can be found on a sticker on the driver’s side door jamb, on a metal plate on the driver’s side dashboard visible through the windshield, or on your vehicle’s registration and insurance documents.