Is Your Vehicle’s Brain Failing? Get Back on the Road with Confidence.
There’s nothing more frustrating than a vehicle that won’t run right. Whether you’re dealing with a car that won’t start, stalls unexpectedly, or has a persistent check engine light, the source of the problem is often the Engine Control Module (ECM). As the central computer of your vehicle, a faulty ECM can cause a cascade of confusing and costly issues. This isn’t just a part; it’s the solution to restoring your vehicle’s performance and your peace of mind.
We take the guesswork and high costs out of the equation. This genuine GM ECM, compatible with part number 12668991, arrives at your door fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We install the latest, most stable software updates from GM, ensuring your engine, transmission, and emissions systems operate precisely as they were designed to. This is the definitive, dealership-alternative solution you’ve been searching for.
Common Symptoms & Your Solution
If you’re experiencing any of the following, a failing ECM is a likely culprit. This pre-programmed module is designed to be the direct solution for:
- Check Engine Light (CEL): Persistent illumination with codes like U0100 (Lost Communication with ECM) or other P-codes pointing to module failure.
- No-Start or Hard-Start Condition: The engine cranks but refuses to start, or starts only after extended cranking.
- Poor Engine Performance: Noticeable loss of power, hesitation during acceleration, and rough idling.
- Reduced Fuel Economy: A sudden and unexplained drop in your vehicle’s MPG.
- Erratic Transmission Shifting: Harsh or delayed gear changes as the ECM fails to communicate properly with the transmission controller.
Features & Tangible Benefits
- ✔ VIN-Programmed for Your Vehicle: This ECM arrives ready for installation. We flash it using your VIN, eliminating the need for an expensive trip to the dealership for programming.
- ✔ Plug & Play Installation: Simply disconnect the old module and connect this new one. In most cases, no complicated relearn procedures are required.
- ✔ Loaded with Latest GM Software: We ensure your module has the most recent factory updates, which can solve underlying drivability issues and improve overall efficiency.
- ✔ Broad GM Compatibility: This single unit is a verified replacement for a wide range of vehicles, from the Chevy Spark and Cruze to the Silverado and Express van, ensuring a perfect fit. (See full fitment list for details).
- ✔ One-Year Protection: This unit is backed by our one-year replacement warranty.
An Expert’s Insight: More Than Just a Box
As a technician with over two decades of experience, I’ve seen people chase expensive sensor and wiring repairs when the root cause was the ECM all along. Think of the ECM as the conductor of an orchestra; if it’s giving the wrong signals, nothing else performs correctly. A properly programmed module doesn’t just make the engine run—it ensures your transmission shifts smoothly, your fuel injectors fire with precision, and your emissions are kept in check. Investing in a correctly programmed ECM isn’t just fixing a problem; it’s restoring the entire integrated system of your vehicle to factory specification.
Frequently Asked Questions
What do I need to do after I place my order?
After you complete your purchase, you must provide us with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship the module without it. You can typically send it to us through the order messaging system.
Is this ECM truly plug-and-play?
Yes, for the vast majority of vehicles, this module is a direct plug-and-play solution. You install it, and the vehicle will start and run correctly. Some vehicles with advanced anti-theft systems may require a simple security relearn procedure, which can often be done without special tools.
Does this part number have to match mine exactly?
This ECM (12668991) is a direct replacement for several other part numbers, including 12668866, 12668994, 12643636, and others listed in the fitment data. As long as your vehicle is on the compatibility list, this module will function correctly once programmed to your VIN.
Will this fix my check engine light?
If the check engine light is caused by a faulty ECM, then yes, this part will resolve the issue. However, it’s always recommended to have the codes professionally diagnosed to ensure the ECM is the true source of the problem and not a separate sensor or wiring issue.
Where can I find my VIN?
Your VIN is a 17-digit number located on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, and on your vehicle’s registration and insurance documents.