Is Your Truck Running Rough, Stalling, or Refusing to Start?
If you’re dealing with a frustrating check engine light, erratic engine behavior, or transmission shifting problems in your 1998-1999 GMC 2500, a failing Powertrain Control Module (PCM) is often the culprit. Over two decades in the shop, I’ve seen countless GM trucks from this era sidelined by a faulty computer. The PCM is the brain of your vehicle, and when it goes, it can cause a cascade of issues that are difficult to diagnose. This isn’t just a part; it’s the solution to getting your reliable truck back on the road.
This is a dependable, used OEM PCM that has been meticulously tested and is ready for service. We take the guesswork and high dealership costs out of the equation by programming it specifically for your vehicle before it ever leaves our hands.
The Simple, Reliable Fix You Need
Forget about expensive diagnostic fees and the hassle of getting a new module programmed at a dealership. We handle the critical programming for you.
- โ VIN-Specific Programming: We flash this module with the latest GM software updates using the VIN you provide. This ensures perfect communication with your truck’s systems.
- โ Solves Common Problems: Directly addresses issues like harsh shifting, false sensor codes, intermittent stalling, and no-start conditions.
- โ Cost-Effective Solution: Get a fully functional, programmed computer for a fraction of the cost of a new unit from a dealer.
- โ Guaranteed Compatibility: This module is a direct replacement for multiple part numbers, ensuring a perfect fit for a wide range of GM trucks and vans.
From the Shop Floor: A Real-World Scenario
“A customer’s ’99 Tahoe came in last week with these exact symptoms: it would crank but not start when warm, and the fuel gauge was acting erratically. They had already replaced the fuel pump and ignition coil with no luck. After a quick scan showed no communication with the PCM, we knew where to look. A failing driver inside the original computer was the root cause. We installed one of our pre-programmed PCMs, performed the security relearn, and the truck fired right up and has been running perfectly ever since. It’s a classic failure on these vehicles.”
Easy Installation to Get You Running Again
You can install this module yourself with basic hand tools. No advanced mechanical skill is required. Just follow these steps, and be sure to read our Pro Tip below about the security system.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On most of these trucks and vans, the PCM is located in the engine compartment on the driver’s side, near the fender or firewall.
- Disconnect the Harnesses: Carefully lift the levers on the multi-pin connectors to release them from the module. There are typically two or three colored connectors.
- Remove the Old Module: Unbolt the PCM and its bracket from the vehicle.
- Install the New PCM: Mount your new, pre-programmed module in the same location.
- Reconnect Everything: Securely plug the wiring harnesses back in and reconnect the negative battery terminal.
Expert Pro Tip: Don’t Skip the Security Relearn!
After installing your new 1998-1999 GMC 2500 PCM, your vehicle’s anti-theft system (GM Passlock/VATS) will likely prevent it from starting. This is normal. You must perform a security relearn procedure. It’s simple and requires no tools: Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this cycle three times. On the final cycle, the truck should start. This step syncs the new PCM with your vehicle’s security system.
Guaranteed Fitment for Your Vehicle
This Electronic Control Module is a direct replacement for part numbers 16250279, 09355699, 16266645, 16258815, and 09366810. It is compatible with a wide variety of 1998 and 1999 GM models. Please verify your vehicle is on the list below and that your original module carries one of the compatible service numbers.
Compatible Models Include (but not limited to):
- Chevrolet/GMC 1500, 2500, & 3500 Pickups (Gasoline)
- Chevrolet Tahoe & GMC Yukon (Gasoline)
- Chevrolet Suburban 1500 & 2500 (Gasoline)
- Chevrolet Express & GMC Savana Vans 1500, 2500, 3500 (Gasoline)
- Cadillac Escalade
- Chevrolet Astro & GMC Safari
- Chevrolet S10, GMC Sonoma, Oldsmobile Bravada, Isuzu Hombre (4.3L V6)
IMPORTANT: After purchasing, please send us a message with your vehicle’s 17-digit VIN. We cannot ship your order until we have this information to program the module correctly.