Is Your Truck Running Rough? Get the Right Fix, The First Time.
If you’re dealing with a persistent check engine light, erratic engine behavior, or a vehicle that just won’t start, a failing Engine Control Module (ECM) is often the culprit. For the hardworking owner of a late-90s GM truck, van, or SUV, this isn’t just an annoyance—it’s a roadblock. This genuine GM engine computer, service number 9355699, is the definitive solution to get your vehicle back on the road and running with factory precision. We take the guesswork out of the repair by pre-programming this module to your vehicle’s specific VIN, ensuring a seamless installation.
Common Symptoms & Your Direct-Fit Solution
A faulty ECM can cause a wide range of frustrating issues that can be difficult to diagnose. If your vehicle is experiencing any of the following, this module is the likely solution:
- No-Start Condition: The engine cranks but refuses to start.
- Stalling or Rough Idle: Your vehicle stalls unexpectedly at stops or idles poorly.
- Poor Fuel Economy: A sudden and unexplained drop in MPG.
- Check Engine Light with Communication Codes: Diagnostic Trouble Codes (DTCs) like P0601 (Internal Control Module Memory Check Sum Error) or other communication-related faults.
- Erratic Transmission Shifting: Harsh or incorrect gear changes controlled by the PCM.
This Programmed 9355699 ECM is the reliable, cost-effective answer to these problems, restoring communication between your vehicle’s critical systems.
Features & Benefits
- ✔ Plug & Drive Installation: This unit arrives flashed with the latest GM software updates specifically for your vehicle’s VIN. This eliminates the need for expensive dealership programming tools or trips.
- ✔ Genuine OE Reliability: Sourced from a salvaged vehicle, this is an original equipment part, not a failure-prone aftermarket clone. It ensures perfect compatibility and the durability your truck demands.
- ✔ Broad Compatibility: A direct replacement for multiple service numbers, including 09355699, 16266645, 16250279, 16258815, and 09366810.
- ✔ Restored Performance: Corrects engine and transmission issues, improves fuel economy, and ensures your vehicle operates exactly as the engineers intended.
- ✔ Purchase with Confidence: This unit is backed by our one-year replacement warranty.
An Expert’s Note on VIN Programming
As a technician with over two decades of experience, I can’t stress this enough: on these late-90s GM vehicles, you can’t just swap a computer from another truck and expect it to work. The Vehicle Anti-Theft System (Passlock), fuel injector pulse width, and transmission shift points are all tied to the original VIN. Our programming service handles all of that for you. We load your vehicle’s unique calibration file onto this ECM, making it a true plug-and-play part that communicates correctly with all other modules right out of the box. This is the crucial step that separates a successful repair from a frustrating dead end.
Frequently Asked Questions
What information do you need from me?
After you complete your purchase, you must provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). We cannot program and ship your ECM without it.
Will I need to do any additional programming?
No, the core engine and transmission programming is complete. However, on many GM vehicles of this era, you may need to perform a simple security relearn procedure to sync the Programmed 9355699 ECM with your vehicle’s anti-theft system. This procedure takes about 30 minutes and can be done without any special tools. We can provide instructions upon request.
How do I find my VIN?
Your VIN can be found on a metal plate on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Is this part tested?
Yes. While this is a used part from a salvaged vehicle, it is a genuine OEM component. It is inspected and then fully programmed to your VIN with the latest stable software from GM, which confirms its functionality.
Will this computer fit my vehicle?
This ECM fits a wide variety of 1998-1999 GM trucks, vans, and SUVs that use service number 9355699 or one of its interchanges. Please review the detailed fitment list on this page to confirm compatibility with your specific year, make, and model.