Restore Peak Performance to Your GM Truck or Van
Is your 1998-1999 GMC Savana, Chevy Express, or other compatible GM vehicle suffering from frustrating engine problems? Issues like stalling, rough idling, poor fuel economy, or a persistent check engine light are often traced back to a failing Powertrain Control Module (PCM). This computer is the brain of your vehicle, and when it malfunctions, it can cause a cascade of performance issues. This replacement PCM, part number 16266645, is the reliable and cost-effective solution to get your vehicle running smoothly again.
We take the guesswork and hassle out of the repair. Unlike a generic part from a local auto parts store, this genuine used OEM module is programmed specifically for your vehicle using your VIN. This critical step ensures that all factory settings for your engine, transmission, and emissions systems are correctly loaded. We flash the unit with the latest GM software updates, so you’re not just replacing the part—you’re getting the most current operational logic for your vehicle. Simply provide your VIN after purchase, and we’ll handle the programming before it ships. This makes installation a straightforward, plug-and-play process for you or your mechanic.
From the Diagnostic Bay
We had a 1998 Chevy Express 2500 work van come into the shop that was driving the owner crazy. It would run fine for a while, then suddenly die at a stoplight. Sometimes it wouldn’t restart for 10-15 minutes. He’d already replaced the fuel pump and ignition coil with no luck. After hooking up our scanner, we noticed erratic data from the PCM and a few communication error codes. We suspected an internal failure in the module. Instead of a costly new unit from the dealer, we sourced a quality used PCM, programmed it to the van’s VIN, and installed it. The van fired right up and ran perfectly. We took it on a long test drive with multiple stops, and the stalling issue was completely gone. A simple PCM swap got this reliable workhorse back on the job.
Solving Your Vehicle’s Engine Problems with a 1998-1999 Savana 2500 PCM
The PCM is responsible for managing dozens of critical functions. When it begins to fail, the symptoms can be varied and confusing. Replacing your faulty module can resolve a wide range of problems and restore the drivability and reliability you depend on.
Common Symptoms of a Failing PCM:
- ✔ Check Engine Light is illuminated with various trouble codes.
- ✔ Engine stalls unexpectedly or is difficult to start.
- ✔ Rough or erratic idling.
- ✔ Noticeable decrease in fuel mileage.
- ✔ Harsh or incorrect transmission shifting.
- ✔ The vehicle fails to pass an emissions test.
- ✔ Complete no-start condition where the engine cranks but won’t fire.
- ✔ Communication errors with diagnostic scan tools.
Guaranteed Compatibility and Simple Installation
This module is a direct replacement for several part numbers, including 16266645, 09355699, 16250279, 16258815, and 09366810. It fits a wide array of popular GM trucks and vans from the 1998-1999 model years, such as the Chevrolet Silverado, GMC Sierra, Tahoe, Yukon, Suburban, and many more. Because we program the unit to your VIN, you can be confident in its compatibility. Installation typically involves disconnecting the battery, removing the old module, installing the new one, and reconnecting the battery. In some cases, a Crankshaft Variation Relearn (also known as a CASE relearn) may be required, which can be performed by most professional scan tools.
Frequently Asked Questions
Do I need to have this computer programmed?
No, we handle the programming for you! After you complete your purchase, simply provide us with your vehicle’s 17-digit VIN. We will flash the module with the correct GM software and updates for your specific vehicle before shipping it out. It will arrive ready to install.
Is this a new part?
This is a high-quality, genuine OEM part sourced from a salvaged vehicle. Each unit is inspected and tested to ensure it is fully functional before being programmed and shipped. This provides OEM reliability at a fraction of the cost of a new unit from a dealership.
What is a CASE Relearn and will I need to do it?
A CASE (Crankshaft Angle Sensor Error) Relearn is a procedure that synchronizes the new PCM with your engine’s crankshaft position sensor. After installing the new PCM, some vehicles may require this procedure to clear a P1336 trouble code and turn off the check engine light. It’s a simple process that can be completed in minutes with most professional-grade automotive scan tools.
Where is the PCM located on my vehicle?
On most of the compatible trucks and vans like the Savana, Express, Tahoe, and pickups, the PCM is located in the engine compartment, typically on the driver’s side near the battery or on the inner fender.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM also controls transmission functions, including shift points and line pressure. If your shifting issues are caused by faulty electronic commands from a failing PCM, this replacement part will correct them. However, it will not fix internal mechanical issues within the transmission itself.