Restore Your Van’s Performance and Reliability
Is your GMC Savana or Chevy Express van giving you headaches? If you’re dealing with a persistent check engine light, rough idling, stalling, or a frustrating no-start condition, a failing Powertrain Control Module (PCM) is often the culprit. As the ‘brain’ of your vehicle’s engine and transmission, when the PCM goes bad, it can cause a wide range of confusing and intermittent problems. After 20+ years in the shop, I’ve seen how heat, vibration, and age can degrade the internal circuits on these modules, leading to issues that are tough to diagnose.
This isn’t just a replacement part; it’s a complete solution. We take a quality, tested PCM and program it specifically for your vehicle using your VIN. This service includes loading the very latest factory software from GM, which often corrects drivability issues and improves performance over the original programming your vehicle came with. You get a module that’s ready to install right out of the box, saving you a costly trip to the dealership for programming.
From the Diagnostic Bay
I remember a 2001 Express 2500 work van that came in with the most frustrating issue. The owner said it would randomly stall at stoplights, but only after it was fully warmed up on a hot day. No codes, no warning. We checked fuel pressure, sensors, wiring—everything looked perfect. On a hunch, I monitored the PCM data stream while using a heat gun to gently warm the module. Sure enough, as the PCM’s internal temperature rose, the injector pulse width data started getting erratic just before it stalled. A new, pre-programmed PCM fixed it for good. These intermittent thermal failures are exactly why a reliable replacement is so critical.
Is Your GM Van or Truck Showing These Symptoms?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, it might be time for a replacement:
- ✔ Check Engine Light is on with communication codes (U-codes) or internal processor fault codes (P0601, P0602, P0606).
- ✔ Engine cranks but refuses to start.
- ✔ Rough or unstable idle.
- ✔ Poor fuel economy.
- ✔ Harsh or erratic transmission shifting.
- ✔ Vehicle fails emissions testing.
- ✔ Intermittent stalling or hesitation, especially when warm.
A Straightforward Guide to Installation
Installing your new 1999-2002 Savana 2500 PCM is a job most DIYers can handle in under an hour. Follow these general steps to get your vehicle back on the road:
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most Savana/Express vans, the PCM is located in the engine compartment on the driver’s side, near the battery or firewall. It’s a silver metal box with several large electrical connectors.
- Disconnect Connectors: Carefully unclip and remove all electrical harness connectors from the old PCM. They often have locking tabs that need to be released. Avoid pulling on the wires themselves.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket.
- Install the New Module: Bolt your new, pre-programmed PCM into the bracket.
- Reconnect Everything: Firmly plug all electrical connectors back into the new module until they click into place. Reconnect the negative battery terminal.
- Security Relearn (Important!): After installation, you will likely need to perform a security relearn procedure so the vehicle recognizes the new PCM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times. Your vehicle’s service manual will have the exact steps.
Verified Vehicle Compatibility List
This module is a direct fit for a wide range of GM trucks and vans. Please verify your part number (16263494, 16265035, 8162634940, or 21811787) and vehicle from the list below. This is a partial list of common applications:
- Chevrolet Express / GMC Savana 1500/2500/3500 Van (1999-2002)
- Chevrolet Silverado / GMC Sierra 1500/2500/3500 Pickup (1999-2000)
- Chevrolet Tahoe / GMC Yukon (1999-2000)
- Chevrolet Astro / GMC Safari (1999-2001)
- Chevrolet S10 / GMC Sonoma (1998-2000)
- Chevrolet Blazer / GMC Jimmy (1998-2000)
- Oldsmobile Bravada / GMC Envoy (1998-2000)
- Cadillac Escalade (1999-2000)
- Isuzu Hombre (1998-2000)
Note: Compatibility can depend on specific options. Providing your VIN for programming is the best way to guarantee a perfect match.
Frequently Asked Questions
How does the programming process work?
After you place your order, you will need to provide us with your vehicle’s 17-digit VIN. We use this to load the correct, updated GM software for your specific vehicle configuration before we ship the module to you.
Is this a plug-and-play part?
Mostly, yes. Because it arrives programmed, you will not need a dealer’s scan tool. However, you will need to perform a security relearn procedure after installation, which can be done without special tools. This syncs the new PCM with your vehicle’s anti-theft system.
Do I need to send my old PCM back?
No, there is no core charge or need to return your old, faulty module. You can recycle it locally or simply dispose of it.
Will this fix my specific problem?
This module will correct issues directly caused by a failing PCM. While the symptoms listed are common indicators, we always recommend a proper diagnosis by a qualified mechanic to confirm the PCM is the point of failure before ordering.
What if I order the wrong part?
We strongly encourage you to match the part number on your existing module (e.g., 16263494) to the ones listed. By providing your VIN, we double-check compatibility to prevent errors, ensuring you get the right part the first time.