Restore Peak Performance to Your GMT400 Truck
Is your 1998 or 1999 GMC 2500 running rough, stalling, or showing a persistent Check Engine Light? These are classic signs of a failing Powertrain Control Module (PCM), the central computer that manages your truck’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 bad computer keep your reliable truck off the road. This fully programmed PCM is the direct, effective solution to get your vehicle running properly again.
From the Diagnostic Bay
We had a customer with a ’99 Chevy K2500 with the 5.7L Vortec who was at his wit’s end. He’d replaced the fuel pump, distributor, plugs, and wires chasing an intermittent stalling issue. The truck would run fine for days, then suddenly die at a stoplight and refuse to restart for an hour. No consistent codes were being stored. After checking all the wiring and grounds, we hooked up a scope to the PCM outputs. We found the injector pulse signals would randomly drop out. We swapped in one of our pre-programmed modules, and the problem was solved instantly. He had spent over a thousand dollars on parts he didn’t need, when the root cause was the original PCM failing under heat.
Symptoms of a Failing 1998-1999 GMC 2500 PCM
- ✔ Persistent Check Engine Light (CEL) with various codes.
- ✔ Engine stalling, stumbling, or misfiring.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Complete no-start condition where the engine cranks but won’t fire.
- ✔ Noticeable decrease in fuel economy.
- ✔ Failure to communicate with diagnostic scan tools.
- ✔ Intermittent issues that are difficult to reproduce.
A Plug-and-Play Solution Programmed for Your Truck
This isn’t just a part in a box; it’s a complete service. We take a quality, tested, used OEM computer and flash it with the latest official GM software calibration specifically for your vehicle. All you need to do is provide us with your truck’s 17-digit Vehicle Identification Number (VIN) during or after checkout. This ensures that the module is perfectly matched to your engine, transmission, and factory options. This crucial step eliminates the need for an expensive trip to the dealership for programming, saving you time and money.
This module is a direct replacement for several part numbers, including 09366810, 09355699, 16266645, 16250279, and 16258815. It is guaranteed to be compatible with a wide range of GM trucks and vans from that era, as detailed in our fitment list. Once installed, you may need to perform a simple security relearn procedure, which can typically be done in your driveway without any special tools.
Frequently Asked Questions
Do I need to get this computer programmed?
No. We handle all the programming for you before we ship the part. Simply provide your vehicle’s VIN, and it will arrive ready to install. This is a plug-and-play solution.
Is this a new part?
This is a high-quality, inspected, and tested used OEM part sourced from a salvaged vehicle. This ensures OEM reliability and perfect fitment at a fraction of the cost of a new module, which are often no longer available from the manufacturer.
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to load the exact GM factory software and calibrations for your truck’s specific engine, transmission, and emissions equipment. This ensures seamless operation and compatibility.
Will I need to do anything after I install it?
In most cases, you will need to perform a simple security relearn procedure (often called Passlock or Passkey relearn). This procedure syncs the new computer with your vehicle’s anti-theft system and can be done without special tools. Instructions are widely available online or in service manuals.
Where is the PCM located on my truck?
On most 1998-1999 GMC and Chevrolet full-size trucks and SUVs, the PCM is located in the engine compartment on the driver’s side, near the firewall or inner fender.