Restore Your Van’s Performance and Reliability
Is your 1998 Chevrolet Express 2500 Van running rough, stalling unexpectedly, or showing a persistent check engine light? These are classic signs of a failing Powertrain Control Module (PCM), the central computer that manages your vehicle’s engine and transmission. A faulty PCM can lead to a cascade of frustrating issues, from poor fuel economy and erratic shifting to a complete no-start condition. Don’t let a malfunctioning module keep your workhorse van off the road. This direct-fit replacement PCM, part number 16250279, is the definitive solution to get your vehicle running like new again.
From the Diagnostic Bay
We had a 1998 GMC Savana (a sibling to the Express) come into the shop with a complaint that was stumping everyone. The owner said it would randomly lose power and the transmission would shift hard, but there were no consistent trouble codes—just a generic communication error that would pop up now and then. We checked the wiring, sensors, and even the transmission fluid. Everything looked fine. On a hunch, we monitored the live data from the PCM and noticed the sensor readings would occasionally drop out completely for a split second. That pointed to an internal failure in the module. We installed a correctly programmed PCM, and the van immediately ran perfectly. It’s a reminder that these intermittent, ghost-like problems are often rooted in the vehicle’s main computer.
Diagnosing a Faulty 1998 Express 2500 PCM
The Powertrain Control Module is the brain of your vehicle’s operation. When it begins to fail, the symptoms can be widespread and sometimes misleading. If you’re experiencing any of the issues below, it’s highly likely your PCM is the culprit. This replacement module is designed to correct these problems and restore the precise factory-calibrated performance your van needs to operate efficiently.
Common Symptoms of PCM Failure
- ✔ Check Engine Light: The light is on, and you may have codes related to sensor circuits, communication errors (U-codes), or random misfires.
- ✔ Poor Engine Performance: Noticeable loss of power, hesitation during acceleration, rough or unstable idling, and decreased fuel mileage.
- ✔ Stalling or No-Start: The engine may stall for no reason while driving or refuse to start at all, even with a good battery and starter.
- ✔ Erratic Transmission Shifting: The automatic transmission may shift harshly, at the wrong RPMs, or get stuck in one gear (limp mode).
- ✔ Failed Emissions Test: A malfunctioning PCM can prevent the engine from running cleanly, leading to an automatic failure at the emissions station.
- ✔ Intermittent Electrical Issues: Gauges on the dashboard may act erratically or other electronic systems might behave unpredictably.
A True Plug-and-Play Solution
The biggest hurdle in replacing a modern vehicle computer is programming. This module eliminates that problem entirely. We handle the complex part for you. When you place your order, simply provide us with your vehicle’s 17-digit VIN. Our technicians will then flash the module with the latest, most up-to-date GM factory software specific to your 1998 Express 2500 Van. This ensures that all engine parameters, transmission shift points, and emissions controls are perfectly calibrated. When the part arrives, it’s ready for installation without any need for expensive trips to the dealership for programming. This module is a direct replacement for part numbers 16250279, 09366810, and 09355699 and fits a wide range of 1998-1999 GM trucks, vans, and SUVs.
Frequently Asked Questions
Do I need to have this PCM programmed?
No. This PCM comes fully programmed to your vehicle’s specific VIN. We flash it with the latest GM software before it ships, making it ready for installation right out of the box.
What is a VIN and why do you need it?
The VIN (Vehicle Identification Number) is a unique 17-digit code for your van. It contains information about the engine, transmission, and other options. Providing your VIN allows us to load the exact correct software for your vehicle’s configuration.
Is any additional setup required after installation?
In many cases, no additional setup is needed. However, some GM vehicles of this era may require a security relearn procedure (often called a CASE relearn or Passlock relearn) to sync the new PCM with the anti-theft system. This is a simple procedure that can typically be done without special tools. Instructions are widely available online or in service manuals.
Where is the PCM located on my 1998 Express Van?
On the 1998 Express and Savana vans, the PCM is typically located in the engine compartment on the driver’s side, often near the battery or mounted to the inner fender.
Will this fix my check engine light?
If the check engine light and associated codes are caused by a faulty PCM, then yes, this replacement part will resolve the issue. It’s crucial to ensure that the root cause of the problem is the module itself and not a separate faulty sensor or wiring issue.