Is Your 1998 GMC Envoy or GM Truck Running Rough?
If you’re dealing with frustrating issues like a persistent check engine light, erratic shifting, a no-start condition, or poor fuel economy, a failing Powertrain Control Module (PCM) is often the culprit. As the brain of your vehicle, when the PCM starts to fail, it can cause a cascade of problems that are often misdiagnosed. I’ve spent over two decades under the hood of these trucks, and I’ve seen drivers replace perfectly good sensors and fuel pumps, only to find the core issue was the engine computer itself.
“A customer’s ’98 Chevy Blazer S10, which uses this exact same computer, came into my shop last week with an intermittent no-start and a random misfire code that wouldn’t clear. After confirming the wiring harness was solid, we swapped in one of our pre-programmed PCMs. The truck fired right up and ran smoother than it had in years. The original module’s internal voltage regulator had become unstable from years of heat cyclesโa common failure I’ve diagnosed on hundreds of these GM platforms.”
The Direct, Reliable Solution: A VIN-Programmed PCM
This isn’t just a replacement part; it’s a complete solution. We are offering a genuine, used OEM Powertrain Control Module that will be professionally programmed to your vehicle’s specific Vehicle Identification Number (VIN). This critical step ensures that the computer has the correct software and calibrations for your engine, transmission, and options, straight from GM’s latest updates. It’s the key to a successful and lasting repair.
- โ VIN Programmed for Your Vehicle: Simply provide your VIN at checkout, and we handle the programming. It arrives ready to install.
- โ Resolves Common Failure Symptoms: Effectively addresses issues like harsh shifting, engine stalling, false sensor codes, and communication errors.
- โ Broad Compatibility: This module, service number 09366810, is a direct replacement for multiple part numbers including 09355699, 16266645, and more, fitting a wide range of GM trucks, vans, and SUVs from 1998-1999.
- โ Cost-Effective Repair: Get a reliable, tested OEM part that’s been programmed without the high cost and hassle of a dealership visit.
Simple Installation for the DIYer or Professional
Replacing the PCM on your 1998 Envoy is a straightforward job. The module is typically located in the engine bay, making it accessible. Follow these steps for a smooth installation:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On the 1998 GMC Envoy, you’ll find the PCM in the right-hand (passenger side) front of the engine compartment. On other models like Chevy Pickups or Suburbans, it’s often on the left-hand side.
- Disconnect Connectors: Carefully unclip and remove the electrical harness connectors from the old PCM. Inspect the pins on the connectors for any corrosion or damage and clean them if necessary.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM, reconnect the electrical harnesses securely, and then reconnect your battery terminal.
- Final Steps: In some cases, a security relearn procedure (often called a Passlock relearn) may be required. This is a simple process that typically involves turning the key to the ‘ON’ position for 10-15 minutes and can be done without special tools.
Don’t let a faulty computer keep your reliable GM truck off the road. This VIN-programmed PCM is the most dependable way to restore your vehicle’s performance and operational integrity. Confirm your part number from the list provided and place your order to get started on a permanent fix.