Is Your GM Truck or Van Running Rough, Stalling, or Not Starting?
If you’re dealing with frustrating engine problems on your late-90s GM vehicle, a failing Powertrain Control Module (PCM) is a very common culprit. Over my 20+ years in the shop, I’ve seen these symptoms countless times: a check engine light that won’t go away, harsh or erratic shifting, a sudden no-start condition, or a complete loss of communication with your scan tool. Don’t let a bad computer keep your workhorse off the road. This is a reliable, tested, and VIN-programmed PCM that serves as a direct-fit solution.
From the Shop Floor: A Real-World Diagnosis
A customer’s ’99 Savana 3500 work van was towed in last month with a classic no-start. The engine would crank but never fire. The first thing I checked was communication with the PCM using my scan tool—nothing. It was completely unresponsive. After confirming the PCM had proper power and ground at the connector pins (a critical first step!), it was clear the module itself had failed internally. This is a textbook failure on these workhorse vans and trucks. We swapped in a VIN-programmed unit just like this one, and the van fired right up and ran perfectly. This part saves you the diagnostic headache and the expensive trip to a dealership.
The Smart Solution: Pre-Programmed and Ready for Installation
Forget about paying for expensive dealership programming or towing fees. We take the hassle out of the repair. When you purchase this module, simply provide us with your vehicle’s 17-digit VIN. We will then flash the unit with the latest GM-certified software specific to your vehicle’s configuration. This ensures all parameters for the engine and transmission are correct right out of the box.
- ✔ VIN Programmed: Flashed with the newest GM updates for your specific vehicle.
- ✔ Cost-Effective Repair: A high-quality used part that provides exceptional value.
- ✔ Solves Common Issues: Corrects problems like no-start, poor fuel economy, check engine lights, and erratic transmission behavior.
- ✔ Broad Compatibility: A direct replacement for a wide range of popular GM trucks, vans, and SUVs.
Simple Plug-and-Play Installation Guide
Installing your replacement 1998-1999 Express 3500 PCM is straightforward. While the exact location varies slightly by model (see fitment list), the process is generally the same. On most Express/Savana vans, you’ll find it in the engine compartment on the driver’s side.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: Find the existing module in your engine bay. It will have several large electrical connectors.
- Disconnect Connectors: Carefully unlatch and remove all electrical harnesses from the old PCM. Inspect the connectors for any corrosion or bent pins and clean them if necessary.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt your new, pre-programmed PCM into the mounting bracket.
- Reconnect Everything: Securely plug all electrical connectors back into the new module. Reconnect the negative battery terminal.
- Security Relearn (If Necessary): In most cases, the vehicle will start and run immediately. Some models may require a simple security relearn procedure, which typically involves cycling the key and can be done without any special tools.
Guaranteed Compatibility
This module is a direct replacement for several part numbers, ensuring a perfect fit and function. Please verify that your original module has one of the following numbers printed on its label:
Interchangeable Part Numbers: 09355699, 16266645, 16250279, 16258815, 09366810, 9366810
This 1998-1999 Express 3500 PCM Fits the Following Vehicles:
Please ensure your vehicle is listed below and your original module’s ID is 09355699.
- Astro Van: 1998
- Blazer S10 / Jimmy S15: 1998 (4.3L)
- Bravada: 1998 (4.3L)
- Chevrolet / GMC Pickup 1500, 2500, 3500: 1998-1999 (Gasoline Engines)
- Escalade: 1999
- Envoy: 1998
- Express / Savana Van 1500, 2500, 3500: 1998-1999 (Gasoline Engines)
- Isuzu Hombre: 1998 (4.3L)
- S10 / S15 / Sonoma Pickup: 1998 (4.3L)
- Safari Van: 1998
- Suburban 1500 / 2500: 1998-1999 (Gasoline Engines)
- Tahoe / Yukon: 1998-1999 (Gasoline Engines)