Get Your GM Van or Truck Running Smoothly Again
Is your 1998-1999 Chevrolet Express 1500 Van running rough, stalling unexpectedly, or showing a persistent check engine light? These are classic signs of a failing Powertrain Control Module (PCM), the electronic brain of your vehicle’s engine. When the PCM starts to go, it can cause a cascade of frustrating issues, from poor fuel economy to a complete no-start condition. As a technician with over two decades of experience, I’ve seen how a faulty PCM can leave owners chasing their tails, replacing perfectly good sensors and parts. This isn’t just a part; it’s the solution to restoring your vehicle’s reliability and performance.
A Technician’s Notebook: The Misleading Misfire
I remember a 1999 GMC Yukon that came into my bay with a random misfire code that just wouldn’t quit. The owner had already replaced the plugs, wires, cap, and rotor. He was convinced it had to be a fuel injector. After connecting my scan tool and watching the live data, I noticed the injector pulse width was erratic on cylinder 3, but only under certain load conditions. Instead of throwing more parts at it, we tested the driver circuit inside the original PCM. Sure enough, it was failing. We installed a quality, VIN-programmed PCM like this one, performed the crankshaft variation relearn, and the truck ran like it just rolled off the factory floor. It’s a powerful reminder that sometimes the problem lies with the component controlling everything else.
Is Your Vehicle Exhibiting These PCM Failure Signs?
A failing engine computer can manifest in many ways. If you’re experiencing any of the following, a faulty PCM could be the culprit:
- ✔ Unexplained Check Engine Light (CEL) with codes like P0601, P0605, or P0606.
- ✔ Engine stalling or shutting off while driving.
- ✔ Rough idling or engine misfires.
- ✔ A noticeable drop in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ The vehicle won’t start, but the battery and starter are good.
- ✔ Failure to pass an emissions test.
The Smart Solution: Pre-Programmed for Your Vehicle
The biggest challenge when replacing a modern engine computer isn’t the physical swap; it’s the programming. Without it, the vehicle won’t run. This used, OEM 1998-1999 Express 1500 VAN PCM solves that problem. We take a thoroughly inspected, salvaged module and flash it with the latest official GM software updates specifically for your vehicle. All we need is your Vehicle Identification Number (VIN) at checkout. This process ensures the PCM communicates correctly with your engine, transmission, and security system, saving you a costly trip to the dealership and the hassle of specialized tools.
A Straightforward Guide to Installation
Replacing the PCM on these GM trucks and vans is a job most DIYers can handle in their own driveway. Follow these steps for a successful installation.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most of these vehicles, the PCM is located in the engine compartment, typically on the driver’s side inner fender or near the battery.
- Disconnect the Connectors: Carefully unclip and remove the electrical harness connectors from the old PCM. These connectors have locking tabs, so be gentle to avoid breaking them.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and secure it with the bolts.
- Reconnect Everything: Firmly plug the electrical connectors into the new PCM until they click into place. Reconnect the negative battery terminal.
- Security & Crank Relearn: In many cases, you will need to perform a security relearn procedure (often involves cycling the key) and a Crankshaft Position Variation (CASE) Relearn using a capable scan tool. This is critical for proper engine operation and clearing certain trouble codes.
Verified Vehicle Compatibility
This Electronic Control Module is a direct fit for a wide range of General Motors trucks and vans. It is compatible with multiple service numbers, including 16250279, 09355699, 16266645, 16258815, and 09366810. Please verify that your vehicle is on the list below and that your original module carries one of the compatible service numbers, most commonly ID 9355699, to ensure a perfect match.
This module fits various 1998-1999 models including:
- ✔ Chevrolet/GMC: 1500/2500/3500 Pickups, Suburban, Tahoe, Yukon
- ✔ Chevrolet/GMC: Express 1500/2500/3500 Vans, Savana 1500/2500/3500 Vans
- ✔ Chevrolet/GMC: Astro, Safari, S10/S15/Sonoma, Blazer S10/Jimmy S15
- ✔ Cadillac: Escalade (1999)
- ✔ Oldsmobile: Bravada (1998)
- ✔ Isuzu: Hombre (1998)
Please refer to the detailed fitment list or contact us with your VIN to confirm compatibility.
What exactly is VIN programming?
What exactly is VIN programming?
VIN programming is the process of loading your vehicle’s specific software and settings onto the PCM. This includes information about your engine, transmission, tire size, and anti-theft system (PassLock/VATS). We use your 17-digit VIN to flash the module with the correct GM-certified calibration, ensuring it works perfectly with your truck or van right out of the box.
Is this part truly plug-and-play?
Because we program it to your VIN, it is as close to plug-and-play as you can get. After physical installation, the only additional step that may be required is a security relearn and/or a CASE (Crankshaft Position Variation) relearn, which can be done with many professional-grade scan tools. This is standard procedure for any PCM replacement on these vehicles.
My original part number isn’t 16250279, but it’s on the cross-reference list. Will this work?
Yes. Manufacturers often use several part numbers for the same component over its production life. This module, identified by hardware ID 9355699, is the correct service replacement for all part numbers listed, including 09355699, 16266645, 16258815, and others. As long as your vehicle is on the compatibility list, we will program it to function identically to your original.
Where does this part come from?
This is a genuine OEM part that has been sourced from a salvaged vehicle. Each module is carefully inspected to ensure the hardware is in excellent condition before it is programmed with the latest GM software for your specific VIN. This provides OEM reliability at a fraction of the cost of a new module.