Is Your GM Truck or Van Running Rough?
If your 1998-1999 GMC Savana, Chevrolet Express, or another compatible GM vehicle is experiencing frustrating and unpredictable issues, a failing Powertrain Control Module (PCM) is a very common culprit. As the central computer of your vehicle, the PCM is responsible for managing everything from fuel mixture and ignition timing to transmission shift points and emissions controls. When it starts to fail, it can cause a cascade of problems that can be difficult to diagnose, leaving you stranded and facing expensive repair bills.
From the Diagnostic Bay
We had a 1999 Chevy Express 3500 work van come into the shop that was driving its owner crazy. It would randomly stall at stoplights and had a harsh 1-2 shift. The owner had already replaced the throttle position sensor and the mass airflow sensor with no improvement. After hooking up our scanner, we noticed erratic data from multiple sensors, but none were consistently faulty. This pointed us directly to the PCM. The internal circuitry was failing, sending corrupt signals throughout the system. A replacement, VIN-programmed PCM like this one had the van running perfectly in under an hour. It’s a reminder that sometimes the ‘brain’ is the problem, not the ‘senses’.
Symptoms of a Failing PCM
- ✔ Check Engine Light is on with various, often inconsistent, trouble codes.
- ✔ Engine stalling, stumbling, or hesitating during acceleration.
- ✔ Rough or erratic idling.
- ✔ Poor fuel economy that has noticeably decreased over time.
- ✔ Harsh or delayed automatic transmission shifting.
- ✔ Complete no-start condition where the engine cranks but won’t fire up.
- ✔ Failure to pass state emissions testing.
The Right Solution: A Programmed 1998-1999 Savana PCM
Don’t let a faulty computer keep your reliable GM truck or van off the road. This is a genuine, used OEM Powertrain Control Module that has been thoroughly tested and is ready for installation. The key to a successful repair is the programming, and we handle that for you. Using the Vehicle Identification Number (VIN) you provide, we flash the module with the latest, most up-to-date software directly from GM. This ensures that the computer is a perfect match for your vehicle’s specific configuration, including its engine, transmission, and emissions equipment.
This plug-and-play approach eliminates the need for expensive dealership programming or specialized tools. By installing a correctly programmed 1998-1999 Savana PCM, you restore the precise calculations needed for optimal engine performance, smooth shifting, and proper fuel efficiency.
Simple, VIN-Matched Process
- Purchase: Complete your order for this module.
- Provide VIN: Reply to your order confirmation email with your vehicle’s 17-digit VIN.
- We Program: Our technicians will flash the unit with your vehicle’s specific software and the latest GM updates.
- Install: Once you receive the PCM, simply disconnect the battery, swap the modules, and reconnect the battery. In some cases, a security relearn procedure may be required, which can typically be done without special tools.
This module is a direct replacement for multiple service numbers, including 09355699, 16266645, 16250279, 16258815, and 09366810. It fits a wide range of GM trucks and vans from 1998-1999, making it a versatile and reliable solution for many owners. Restore your vehicle’s performance and reliability today with a properly programmed 1998-1999 Savana PCM.
Frequently Asked Questions
Do I need to get this computer programmed?
No. We handle all the programming for you before shipment. Simply provide us with your vehicle’s VIN after purchase, and we will load the correct GM software onto the module, making it ready to install right out of the box.
Is this a new part?
This is a high-quality, used OEM part sourced from a salvaged vehicle. Each unit is inspected and tested to ensure it is fully functional before being programmed and shipped.
What is a security or CASE relearn, and will I need to do one?
A security relearn (also known as a Passlock relearn) synchronizes the new PCM with your vehicle’s anti-theft system. A CASE (Crankshaft Angle Sensor Error) relearn helps the PCM compensate for minor variations in the crankshaft position sensor. Many vehicles of this era will require one or both of these simple procedures after installation. They can often be performed without special tools, and instructions are widely available online.
Where can I find my vehicle’s VIN?
Your 17-digit VIN can be found on a metal plate on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Will this computer fix my transmission shifting problems?
In many cases, yes. The PCM controls both engine and transmission functions. Erratic shifting, slipping, and failure to shift are common symptoms of a failing PCM. However, these symptoms can also be caused by mechanical issues within the transmission itself. This part will resolve any electronically-caused shifting problems.
Which part numbers does this unit replace?
This PCM is a direct replacement for service numbers 09355699, 16266645, 9355699, 16250279, 16258815, and 09366810. If your original module has any of these numbers, this part will be a compatible replacement.