Is Your Late-90s GM Truck or Van Running Rough?
If you’re dealing with frustrating issues like a no-start condition, erratic shifting, poor fuel mileage, or a persistent Check Engine Light on your 1998-1999 GM vehicle, a failing Powertrain Control Module (PCM) is often the culprit. Over two decades of service, the original electronics can degrade, leading to communication errors and performance problems that can be tough to diagnose. In my shop, I’ve seen countless GMT400-platform vehicles sidelined by a faulty computer. This isn’t just a part; it’s the solution to getting your reliable workhorse back on the road.
Symptoms of a Failing PCM:
- โ Check Engine Light with communication-related codes (like P0601 or P0605).
- โ Engine cranks but refuses to start.
- โ Harsh or unpredictable automatic transmission shifting.
- โ Unexplained drop in fuel economy.
- โ Stalling, sputtering, or general poor engine performance.
Expert Pro Tip: Check Your Connectors First!
Before you even think about plugging in your replacement PCM, take a minute to carefully inspect the wiring harness connectors. Use a flashlight to look for any signs of green or white corrosion on the pins, or any pins that look bent or pushed back into the connector. A poor connection can mimic PCM failure and can even damage the replacement module. Cleaning them with a dedicated electronics cleaner and a small brush can save you a massive headache. This simple check has saved my customers hundreds of dollars in misdiagnoses over the years.
Direct-Fit Solution: A Programmed 1998-1999 Chevrolet 1500 PCM
This is a reliable, tested, and used OEM PCM that we program specifically for your vehicle. Forget the hassle and high cost of a dealership visit. We use your vehicle’s Vehicle Identification Number (VIN) to flash the module with the latest official GM software updates. This ensures that all factory parameters for your specific engine, transmission, and emissions equipment are perfectly loaded, restoring original performance and communication between all vehicle systems.
Plug-and-Play Installation: No Dealer Visit Required
Installing this module is a straightforward job you can do in your own driveway. Hereโs a basic guide:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most of these trucks and vans (like the Chevy 1500, Tahoe, and Suburban), the PCM is located in the engine compartment, typically on the driver’s side fender or near the battery.
- Disconnect the Harnesses: Carefully unclip and remove the wiring harness connectors from the old module. Note their orientation.
- Swap the Modules: Unbolt the old PCM and remove it. Mount your new, pre-programmed PCM in its place.
- Reconnect Everything: Securely plug the wiring harnesses into the new module. You should feel a solid click. Reconnect your negative battery terminal.
- Start the Engine: Your vehicle is now ready to run with its properly programmed computer. In some cases, a security relearn procedure may be necessary, which can typically be done without special tools.
Guaranteed Compatibility & VIN Programming
This module is a direct replacement for a wide range of part numbers, making it a versatile solution for many popular GM vehicles. After you complete your purchase, simply provide us with your VIN, and we’ll handle the rest. This unit is confirmed to fit vehicles requiring part numbers:
- โ 16250279
- โ 09355699
- โ 16266645
- โ 16258815
- โ 09366810
This PCM is compatible with a vast array of 1998-1999 models, including the Chevrolet & GMC 1500/2500/3500 Pickups, Suburban, Tahoe, Yukon, Express/Savana Vans, Cadillac Escalade, Isuzu Hombre, and more. Please verify the part number ID 9355699 in the fitment list to ensure it matches your application.