Is your 1998 or 1999 Chevrolet Suburban 1500 running rough, stalling, or refusing to start? Are you battling a persistent Check Engine Light with confusing error codes? The problem often lies with a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. This genuine GM engine computer, part number 16258815 (interchangeable with 09355699 and others), is the definitive solution to restore your truck’s performance, reliability, and drivability.
From the Diagnostic Bay
We had a ’99 Tahoe in the shop that was a complete mystery. It would crank but never start, and the owner had already replaced the fuel pump and ignition coil. When we connected our scan tool, it couldn’t communicate with the engine computer at all—a classic sign. After verifying power and ground at the PCM connectors were good, we knew the module itself was the culprit. We installed one of these VIN-programmed units, performed the security relearn, and it fired up on the first try. Don’t waste time and money chasing parts; a faulty PCM can mimic a dozen other problems.
Why Choose a VIN-Programmed 1998-1999 Suburban PCM?
Unlike a generic part from a local auto parts store, this PCM is specifically flashed and configured for your exact vehicle. Before we ship it, we load it with the latest GM-certified software updates using your truck’s unique Vehicle Identification Number (VIN). This critical step ensures that all engine, transmission, and emissions parameters are perfectly calibrated, eliminating compatibility issues and ensuring a smooth installation process. This is not a one-size-fits-all solution; it’s a tailored repair for your specific Suburban.
Common Symptoms of a Failing PCM
- ✔ No-start or intermittent starting issues
- ✔ Rough idling or stalling, especially when warm
- ✔ Poor acceleration and overall loss of engine power
- ✔ Decreased fuel economy
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Check Engine Light is on with codes related to sensors, emissions, or internal module failure
- ✔ Inability to communicate with the PCM using a diagnostic scan tool
Guaranteed Fitment and OEM Reliability
This used OEM computer is sourced from a salvaged vehicle and has been thoroughly inspected to ensure it meets factory standards. It is a direct replacement for several part numbers, including 09355699, 16266645, 16250279, 16258815, and 09366810. Its compatibility extends far beyond the Suburban, fitting a wide range of GM trucks and vans from that era, such as the Chevrolet Tahoe, GMC Yukon, Express/Savana vans, and various pickup models. By providing your VIN, you guarantee that the unit you receive is the correct hardware and software combination for your vehicle’s specific options.
Installation and Post-Install Procedures
Replacing the PCM is a straightforward task for a DIY mechanic or any professional technician. It is typically located in the engine compartment on the driver’s side. The process involves disconnecting the battery, unplugging the electrical connectors from the old module, unbolting it, and installing the new one in its place. After installation, you will likely need to perform a security relearn procedure and a Crankshaft Variation Relearn (also known as a CASE relearn). This synchronizes the new PCM with your vehicle’s anti-theft system and crankshaft position sensor, and is required for proper engine operation. This procedure can be completed by most automotive shops with a capable bi-directional scan tool.
Frequently Asked Questions
Do I need to program this PCM?
No. We handle the programming for you before the part is shipped. Simply provide us with your vehicle’s 17-digit VIN during checkout, and it will arrive ready for installation.
What is a CASE relearn and is it required?
A Crankshaft Variation (CASE) relearn synchronizes the PCM with the crankshaft position sensor. For most 1998-1999 GM vehicles, this procedure is necessary after PCM replacement to prevent a P1336 trouble code and ensure accurate misfire detection. This must be done with a compatible professional scan tool.
Where is the PCM located on my 1999 Suburban?
The PCM is typically found in the engine bay, mounted on the driver’s side inner fender or near the firewall.
Is this a new part?
This is a high-quality, tested used part sourced from a salvaged vehicle. This ensures you get a genuine OEM component with proven reliability at a fraction of the cost of a new dealer part.
What information do you need from me?
After you complete your purchase, we will need your vehicle’s complete 17-digit VIN. This is essential for us to load the correct GM software and calibrations onto the module for your specific truck.