Is Your GM Truck or Van Running Rough, Stalling, or Refusing to Start?
If you’re dealing with frustrating engine problems on your late-90s GM vehicle, a failing Powertrain Control Module (PCM) is often the hidden culprit. Over my 20+ years in the shop, I’ve seen countless owners replace perfectly good fuel pumps, sensors, and ignition components, only to find the real issue was the vehicle’s computer. The symptoms can be maddeningly intermittent, making diagnosis a real challenge for the DIY mechanic.
Common Signs of a Failing GM PCM:
- โ Sudden stalling or cutting out while driving.
- โ Harsh or erratic automatic transmission shifting.
- โ Complete no-start condition, even with a good battery and starter.
- โ Check Engine Light is on with multiple, unrelated trouble codes.
- โ Poor fuel economy and a noticeable loss of power.
- โ The engine seems to run fine one day and terribly the next.
Just last month, a customer brought in his ’99 GMC Sierra 2500 with a no-start condition that had stumped two other shops. It had spark and fuel pressure, but the injectors weren’t firing consistently. Instead of throwing more parts at it, we connected our diagnostic scanner and saw the PCM was failing to communicate properly. We installed one of our pre-programmed modules, and the truck fired up on the first crank and ran perfectly. This is a story I’ve seen play out hundreds of times on these otherwise reliable trucks.
The Direct-Fit Solution: A VIN-Programmed 1998-1999 GMC 3500 PCM
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take a reliable, tested PCM sourced from a salvage vehicle and program it specifically to your truck’s Vehicle Identification Number (VIN). This process ensures all factory settings are correct for your specific engine, transmission, and options. We also load the latest available software updates from General Motors, which can resolve underlying drivability issues you might not have even known were software-related.
Plug-and-Play Installation: No Dealer Visit Required
Forget about towing your truck to a dealership and paying hundreds for programming. This module arrives at your door ready for a straightforward installation. Hereโs how simple it is:
- 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, typically on the driver’s side inner fender or near the battery.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that need to be released. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt your new, pre-programmed PCM into place and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock.
- Power Up: Reconnect the negative battery terminal. The vehicle is now ready to start.
Guaranteed Compatibility
This PCM is a direct replacement for several original equipment part numbers. To ensure a perfect match, please verify that the part number on your current module is one of the following:
- 09355699
- 16266645
- 16250279
- 16258815
- 09366810
While this listing is for the 1998-1999 GMC 3500, this versatile computer fits a massive range of GM vehicles from that era, including Chevrolet and GMC Pickups, Suburbans, Tahoes, Yukons, Express and Savana Vans, and more. Simply provide your VIN after purchase, and we’ll handle the rest, ensuring you get a reliable part that restores your vehicle’s performance and dependability.