Programmed 1998-1999 Tahoe PCM 9366810 | Engine Computer ECM

Restore Your Truck’s Brain and Get Back on the Road

Is your 1998-1999 Chevy Tahoe or GM truck running rough, stalling unexpectedly, or refusing to start? A failing Powertrain Control Module (PCM) is often the culprit behind these frustrating and hard-to-diagnose issues. As the central computer for your engine and transmission, when the PCM falters, your entire vehicle’s performance suffers. This isn’t just an inconvenience; it can be a major reliability problem. This tested, used PCM is the straightforward, cost-effective solution to bring your vehicle back to life.

We take the guesswork and hassle out of the replacement process. Unlike a generic module from a junkyard, this unit is professionally programmed with the latest official GM software updates specifically for your vehicle. Simply provide us with your Vehicle Identification Number (VIN) after your purchase, and we’ll flash the module before it ships. This ensures it’s a true plug-and-play solution, saving you a trip to the dealership and hundreds of dollars in programming fees. Get the right part, programmed correctly, the first time.

Is Your Truck Showing These Symptoms?

A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, it’s a strong indicator that your engine computer needs replacement. This 1998-1999 Tahoe PCM is the definitive fix for these common problems.

• ✔ Check Engine Light is on with communication error codes (e.g., P0601, P0605, P0606).
• ✔ Engine cranks but will not start.
• ✔ Harsh, erratic, or delayed transmission shifting.
• ✔ A noticeable drop in fuel economy for no apparent reason.
• ✔ Intermittent stalling or stumbling while driving.
• ✔ The vehicle’s anti-theft or security light stays on, preventing startup.
• ✔ Inconsistent or non-functional gauges on the instrument cluster.

A Straightforward Guide to Installation

Replacing the PCM on your GM truck is a job most DIYers can handle in their own driveway. Follow these steps for a smooth installation.

1. Safety First: Always disconnect the negative terminal from your vehicle’s battery before working on any electrical components.
2. Locate the PCM: On most 1998-1999 GM trucks and SUVs like the Tahoe and Suburban, the PCM is located in the engine bay, typically on the driver’s side fender well. It’s a silver box with multiple large wiring harness connectors.
3. Disconnect the Harnesses: Carefully unclip and remove all wiring harness connectors from the old PCM. The levers can be stiff, so be gentle but firm. Inspect the pins for any corrosion or damage.
4. Unbolt the Old Module: Remove the bolts or nuts holding the PCM bracket to the vehicle. Set the old module aside.
5. Install the New PCM: Mount your new, pre-programmed PCM in the same location. Secure it with the original hardware.
6. Reconnect Everything: Firmly plug all wiring harnesses back into the new module until they click into place. Reconnect the negative battery terminal.
7. Perform Security Relearn: Your vehicle’s Passlock anti-theft system will likely need to be relearned to the new PCM. The standard procedure is to turn the key to the ‘ON’ position (without starting) for 10-15 minutes, or until the security light stops flashing. Turn the key off for 10 seconds, then repeat the cycle two more times. The vehicle should then start and run normally.

Verified Vehicle Compatibility

This module is a direct replacement for service number 9366810 and interchanges with part numbers 09355699, 16266645, 16250279, and 16258815. It is guaranteed to fit a wide range of GM trucks and vans. Please verify your vehicle is on the list below and that your original module carries one of the compatible part numbers.