Restore Your Truck’s Performance and Reliability
Is your trusty 1998 Chevy S10, GMC Sonoma, or another GM truck from that era giving you headaches? If you’re dealing with a persistent check engine light, erratic engine behavior, poor fuel economy, or a frustrating no-start condition, the culprit is often a failing Powertrain Control Module (PCM). As the electronic brain of your vehicle, a faulty PCM can cause a cascade of problems that are difficult to diagnose. This module is the definitive solution, providing a reliable, pre-programmed replacement that gets you back on the road without a trip to the dealership.
A Technician’s Notebook: The Ghost in the Machine
I remember a 1998 GMC Jimmy that came into my bay with a classic intermittent no-start. The owner had replaced the battery, alternator, and starter. It would run fine for days, then refuse to start for an hour. No codes were stored. After checking all the grounds and power feeds to the PCM, I noticed that wiggling the main connector on the module would sometimes make the fuel pump relay click. These early PCMs are known for internal solder joint failures after decades of heat cycles and vibration. A replacement, pre-programmed PCM like this one solved the problem instantly. It’s a fix I’ve performed hundreds of times on these GM trucks and SUVs.
Is Your GM Truck or Van Showing These Telltale Signs?
A failing computer can manifest in many ways. If you’re experiencing any of the following, a new PCM is the most likely solution:
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- ✔ The engine cranks but won’t start.
- ✔ Unexplained drops in fuel mileage.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Stalling, rough idling, or hesitation during acceleration.
- ✔ Failure to pass an emissions or smog test.
The Power of VIN-Specific Programming
Don’t just buy a computer off a shelf. This 1998 S10 Sonoma PCM is more than just a part; it’s a complete solution. We take your vehicle’s unique Vehicle Identification Number (VIN) and program the module with the latest, most stable software updates directly from GM. This critical step ensures that the computer communicates perfectly with your engine, transmission, and all other onboard systems. It accounts for your specific engine size, transmission type, and factory options, eliminating the guesswork and the need for expensive dealer programming.
A Straightforward Guide to Installation
Replacing the PCM on these vehicles is a job most DIYers can handle in under an hour with basic hand tools. Follow these steps for a successful installation.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait 10-15 minutes to allow all systems to discharge.
- Locate the PCM: On most S10/Sonoma/Blazer models, the PCM is located on the passenger side of the engine compartment, near the firewall or fender. On full-size trucks and vans, it’s typically on the driver’s side front fender.
- Disconnect the Connectors: Carefully unplug the electrical harness connectors from the old module. There are usually release tabs that need to be pressed or lifted. Do not force them.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. It’s typically held in by a few 10mm or 7mm bolts.
- Install the New Module: Bolt your new, pre-programmed PCM into the mounting bracket. Firmly reconnect the electrical harnesses until they click into place.
- Final Step: Reconnect the negative battery terminal. The vehicle may need to perform a security relearn procedure, which typically involves turning the key to the ‘ON’ position for 10-15 minutes before starting.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 16250279, 09366810, and 09355699. It is confirmed to fit the following GM vehicles:
- ASTRO 98-99
- BLAZER S10/JIMMY S15 98
- BRAVADA 98
- CADILLAC ESCALADE 99
- CHEVROLET 1500 PICKUP 98-99
- CHEVROLET 2500 PICKUP 98-99
- CHEVROLET 3500 PICKUP 98-99
- ENVOY 98
- EXPRESS 1500/2500/3500 VAN 98
- GMC 1500 PICKUP 98-99
- GMC 2500 PICKUP 98-99
- GMC 3500 PICKUP 98-99
- ISUZU HOMBRE 98 (4.3L)
- S10/S15/SONOMA 98 (4.3L)
- SAFARI (GMC) 98-99
- SAVANA 1500/2500/3500 VAN 98
- SUBURBAN 1500/2500 98-99
- TAHOE 98-99
- YUKON 98-99
Note: Please verify the part number on your original module to ensure a perfect match. Some models have specific build date options.
Frequently Asked Questions
Frequently Asked Questions
How do I provide my VIN for programming?
After you complete your purchase, simply send us a message with your 17-digit Vehicle Identification Number (VIN). We will program the module before shipping it to you.
Is any additional programming needed after installation?
No. This module arrives ready to install. Because we program it to your VIN, it is a true plug-and-play solution. In some cases, a simple security relearn procedure (turning the key on for 10-15 min) is required, which you can do yourself.
What is the difference between a PCM and an ECM?
The terms are often used interchangeably. PCM (Powertrain Control Module) typically controls both the engine and transmission, while an ECM (Engine Control Module) only controls the engine. For these GM vehicles, this module functions as the PCM.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the original PCM (common codes P0601-P0608), then yes, this part will resolve the issue. It’s important to properly diagnose the vehicle first to ensure the PCM is the root cause.
Is this compatible with my 4.3L V6 S10?
Yes, this 1998 S10 Sonoma PCM is the correct computer for models equipped with the 4.3L (6-262) engine, as well as many other GM engines from this era. Providing your VIN ensures we load the correct software for your specific vehicle configuration.