Restore Peak Performance to Your GM Truck or Van
Is your late-90s Chevy, GMC, or Cadillac truck suffering from perplexing issues like a persistent check engine light, erratic shifting, poor fuel economy, or even a no-start condition? The Powertrain Control Module (PCM), the central computer of your vehicle, is often the culprit. This vital component manages everything from fuel injection and ignition timing to transmission shift points and emissions controls. When it fails, the symptoms can be widespread and frustrating. This replacement PCM, part number 16250279, is the definitive solution to restore your vehicle’s reliability and drivability.
From the Diagnostic Bay
I once had a ’99 GMC Sierra 2500 in the shop that was driving the owner crazy. It would randomly stall at stoplights and had a harsh 1-2 shift. He had already replaced the throttle position sensor and the idle air control valve based on forum advice, but the problem persisted. After hooking up the scanner and seeing no communication with the PCM, we knew where to look. A quick check of the power and ground circuits to the module confirmed they were good. The original PCM had simply failed internally. We installed a VIN-programmed module just like this one, performed the security relearn, and the truck ran like it just rolled off the assembly line. It’s a classic case of symptoms pointing everywhere, but the root cause being the central brain of the operation.
The Importance of a Correctly Programmed 1998 Express 3500 PCM
Unlike a simple mechanical part, a PCM is not a ‘one-size-fits-all’ component. Each module contains software specific to your vehicle’s Vehicle Identification Number (VIN). This programming accounts for the exact engine, transmission, emissions equipment, and other options your truck or van was built with. Installing a non-programmed or incorrectly programmed module can lead to a host of new problems, from a no-start condition to transmission damage. We take the guesswork out of the equation. When you order from us, we use your VIN to flash the module with the latest, most stable software updates directly from GM. This ensures perfect compatibility and optimal performance right out of the box.
Common Symptoms of a Failing GM PCM
- ✔ Persistent Check Engine Light (CEL) with various trouble codes.
- ✔ Engine stalling, stumbling, or misfiring.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A noticeable decrease in fuel economy.
- ✔ The vehicle will crank but fails to start.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Failure to pass state emissions testing.
This module is a direct replacement for service numbers 16250279, 09366810, and 09355699. It is compatible with a wide range of popular GM models from 1998 and 1999, including the Chevrolet Express, GMC Savana, Tahoe, Suburban, S10, Blazer, and many more. Please verify the part number on your original module and consult the detailed fitment list to ensure this is the correct part for your vehicle. Replacing your failing 1998 Express 3500 PCM with this pre-programmed unit is the most effective way to solve complex electronic issues and get your dependable GM vehicle back on the road.
Frequently Asked Questions
Do I need to do any programming after I receive this PCM?
No. We program the module to your vehicle’s specific VIN before shipping. However, you will need to perform a security relearn procedure (also known as a CASE learn or anti-theft relearn) after installation. This is a simple process that can typically be done without special tools and takes about 30 minutes. Instructions are readily available online for your specific model.
Where do I provide my VIN?
After you complete your purchase, you will receive instructions on how to send us your vehicle’s 17-digit VIN. We cannot ship your order until we receive this information, as the programming is essential for the part to function.
Is this a new or used part?
This is a high-quality, tested, and guaranteed functional component. Each module undergoes a rigorous inspection and programming process to ensure it meets or exceeds original equipment specifications.
What if my original part number is slightly different?
This module is a direct replacement for part numbers 16250279, 09366810, and 09355699. If your part number is not on this list, please contact us before ordering to ensure compatibility. Using the wrong hardware can cause functionality issues.
Where is the PCM located on my 1998 Express Van?
On most compatible models, including the Express and Savana vans, the PCM is located in the engine compartment, typically on the driver’s side near the battery or firewall. It’s a silver metal box with multiple large electrical connectors.