Is Your 1998-1999 GM Truck or Van Running Rough?
If you’re dealing with a persistent check engine light, erratic engine behavior, stalling, or a no-start condition, the problem often points directly to a failing Powertrain Control Module (PCM). As a technician with over 20 years of experience, I’ve seen countless GMT400 and Express/Savana platform vehicles sidelined by a faulty engine computer. The electronics inside these modules simply wear out over time from heat and vibration, leading to frustrating and hard-to-diagnose issues.
The Direct-Fit Solution: A Programmed 1998-1999 GMC 1500 PCM
This isn’t just a used part pulled from a shelf. This is a complete, ready-to-install solution. We take a tested, OEM engine computer and flash it with the latest official GM software, tailored specifically to your vehicle’s Vehicle Identification Number (VIN). This critical step ensures that all systemsโfrom the fuel injectors and ignition timing to the transmission shift pointsโoperate exactly as the factory intended. You get a reliable repair without the astronomical cost and scheduling headaches of a dealership visit.
Expert Pro Tip: Pre-Installation Check
Before you even think about plugging in your replacement PCM, take five extra minutes to inspect and clean the main harness connectors. On these 90s GM trucks, I’ve seen more replacement modules damaged by corroded or oil-soaked connector pins than anything else. A small pick and some quality electronics cleaner can prevent a bad connection that could mimic a faulty PCM or even short out your new part. A clean connection is a happy connection.
Key Features & Benefits:
- โ VIN-Programmed for Your Vehicle: We flash the module with your truck’s specific VIN and the newest GM calibration updates, ensuring perfect compatibility.
- โ Plug-and-Play Installation: No need for expensive dealer tools or additional programming. Once it arrives, you can install it yourself in under an hour.
- โ Solves Common Drivability Issues: Effectively resolves problems like harsh shifting, poor fuel economy, intermittent stalling, and false sensor codes.
- โ Cost-Effective Repair: Get your truck back to factory-spec performance for a fraction of the cost of a new module from a dealership.
- โ Broad Compatibility: This module, identified by service number 16266645 or 09355699, fits a wide range of GM trucks, vans, and SUVs from 1998-1999.
Simple Plug-and-Play Installation Guide
You don’t need to be a master mechanic to replace your PCM. Follow these simple steps:
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On most 1998-1999 GM trucks and SUVs, the PCM is located in the engine compartment, typically on the driver’s side fender. On Express/Savana vans, it’s often in the rear of the engine compartment.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old module. Note their color and orientation.
- Swap the Modules: Unbolt the old PCM and secure the new one in its place.
- Reconnect Everything: Firmly plug the wiring harnesses into your new, programmed PCM. Reconnect the negative battery terminal.
- Start and Verify: Start the engine. The check engine light should be off, and your vehicle should run smoothly. A security relearn procedure may be required on some models, which typically involves cycling the key.
Guaranteed Fitment for Multiple Part Numbers
This module is a direct replacement for units with the following part numbers: 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, and 9366810. Please verify the part number on your original module to ensure a perfect match. After your purchase, simply send us your VIN, and we’ll handle the programming before shipment.