Is Your GMC Truck Running Rough, Stalling, or Throwing Codes?
If you’re dealing with frustrating engine problems in your 1998 or 1999 GM truck or van, a failing Powertrain Control Module (PCM) is often the hidden culprit. Over my 20+ years in the shop, I’ve seen countless owners replace expensive sensors and fuel system components, only to find the root issue was the vehicle’s computer all along. A faulty PCM can cause a cascade of confusing symptoms, making diagnosis a real headache.
This isn’t just another part; it’s the brain of your engine, and when it fails, nothing works right. This genuine, used GM PCM, part number 09366810, is the reliable, cost-effective solution to get your truck back on the road and running smoothly.
The Hassle-Free Solution: Programmed & Ready to Install
The biggest hurdle with replacing a PCM is the programming. Typically, you’d have to buy the module, install it, and then have your vehicle towed to a dealership for expensive flashing. We eliminate that entire process. Before we ship this module, we will program it with the latest official GM software, specifically matched to your vehicle’s VIN. It arrives at your door ready for a simple, plug-and-play installation.
- ✔ VIN-Programmed for Your Vehicle: We flash the module with your truck’s specific information, ensuring perfect communication and function.
- ✔ Solves Common Engine Issues: Corrects problems like harsh shifting, poor fuel economy, intermittent stalling, and persistent Check Engine Lights.
- ✔ No Dealer Visit Needed: Save hundreds of dollars and significant downtime by avoiding dealership programming fees.
- ✔ Genuine Used GM Part: Sourced from a salvaged vehicle, this is an authentic component, not a questionable aftermarket clone.
A Real-World Scenario from the Shop
“A customer’s 1999 GMC 2500 came in last week with a classic no-communication code and a random misfire that would come and go. He had already replaced the spark plugs, wires, and even the fuel pump. The diagnostic scanner would connect intermittently. After confirming the wiring harness had good power and ground to the PCM connectors, we knew the module itself had failed internally. A replacement, programmed PCM like this one had him back on the road in under an hour, with the engine running better than it had in years. It’s a fix I’ve performed hundreds of times on these GMT400 platform trucks.”
Easy Installation Guide for your 1998-1999 GMC 2500 PCM
You don’t need to be a master mechanic to install this part. With basic hand tools, you can have your truck running again quickly.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most 1998-1999 GMC/Chevy trucks and full-size vans, the PCM is located in the engine compartment on the driver’s side, near the firewall or inner fender.
- Disconnect the Connectors: Carefully unclip and remove the electrical wiring harnesses from the old PCM. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the mounting bracket holding the old PCM in place and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM in the same location and secure it with the original bolts.
- Reconnect Everything: Firmly plug the wiring harnesses into the new module until they click. Reconnect the negative battery terminal.
- Final Check: Start the engine. The check engine light may stay on for a short period as the system performs its self-checks, but it should run smoothly. A security relearn procedure may be required, which typically involves cycling the key.
Guaranteed Compatibility
This module is a direct replacement for several part numbers. If your original module has any of the following numbers, this part will work for your vehicle, provided it is on the fitment list below: 09355699, 16266645, 16250279, 16258815, or 09366810. Please verify your part number and check the detailed fitment list to ensure you’re ordering the correct component for your truck or van.