Restore Peak Performance to Your GM Vehicle
Is your Corvette, Silverado, or CTS running rough, throwing confusing check engine codes, or refusing to start? A failing Engine Control Module (ECM) is often the culprit, acting as the brain of your vehicle’s engine management system. When it falters, everything from fuel economy to ignition timing can be affected, leading to frustrating and costly diagnostic chases. This replacement ECM, part number 12663391, is the definitive solution to get your vehicle running like new again. It arrives at your door pre-programmed with the latest GM factory software, specifically matched to your vehicle’s VIN. This eliminates the need for an expensive trip to the dealership for programming, making the repair process faster, simpler, and more affordable.
From the Diagnostic Bay
I once had a 2015 Silverado 1500 in the shop with a persistent P0300 random misfire code. The owner had already replaced all the spark plugs, coils, and even the fuel injectors, but the problem remained. Scans showed erratic fuel trim and timing adjustments. Instead of continuing to throw parts at it, we hooked up a scope to the injector and coil control signals coming from the ECM. We found the signals were inconsistent and dropping out intermittently. A new, properly programmed ECM fixed the issue instantly. It’s a powerful reminder that when multiple, seemingly unrelated systems act up, it’s wise to suspect the central controller—the ECM.
Common Symptoms of a Failing 2014-2016 Corvette ECM
A faulty engine computer can manifest in numerous ways. If you’re experiencing any of the following issues, your ECM may be the root cause. This module is a common fix for these problems across a wide range of GM vehicles, not just the Corvette.
- ✔ Check Engine Light is on with various, often unrelated, trouble codes (DTCs).
- ✔ Engine cranks but fails to start.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ Misfires or poor engine performance.
- ✔ Transmission shifting issues or harsh engagement.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Loss of spark or injector pulse signals.
Plug-and-Play Solution Programmed to Your VIN
The biggest hurdle in replacing a modern ECM is the complex programming required to sync it with your vehicle’s specific systems, including the anti-theft (immobilizer) system. We handle that for you. Simply provide your vehicle’s 17-digit VIN during the checkout process, and our technicians will flash the module with the correct, updated software from General Motors. This ensures that when the part arrives, it’s ready for installation. While some vehicles may require a simple security relearn procedure (which can be done without special tools), the core programming is complete, saving you hundreds of dollars in dealer fees.
Wide Compatibility Across the GM Lineup
This module is a direct replacement for a variety of popular GM cars and trucks. Please verify your original part number against the list below to ensure compatibility. This module replaces the following part numbers: 12692067, 12676230, 12656993, 12662034, 12672537, 12673195, 12663391, 12672963, 12669318. Whether you have a C7 Corvette, a hardworking Sierra, or a luxurious Cadillac, this is the reliable component you need to restore proper engine function.
Frequently Asked Questions
Do I need to send my old ECM back (core charge)?
No, there is no core charge for this part. You can keep or responsibly dispose of your old module without any additional fees or hassle.
Is this a simple plug-and-play installation?
Yes, for most vehicles. We program the module to your VIN before shipping. In some cases, a simple security relearn procedure may be required after installation, which typically involves a sequence of key turns and can be done in your driveway without any special tools. Instructions can be easily found online for your specific model.
Where do I provide my VIN?
Please enter your 17-digit Vehicle Identification Number (VIN) in the notes section during checkout or send it to us via email after placing your order. We cannot program and ship the module without your vehicle’s VIN.
Will this fix my vehicle’s specific problem?
This ECM will fix issues directly caused by a faulty engine computer. While the symptoms listed are common indicators of ECM failure, we always recommend a proper diagnosis by a qualified technician to confirm the ECM is the point of failure before ordering. This ensures you are purchasing the correct part for your repair.
Is this a new or used part?
This is a high-quality, tested OEM replacement part. Each unit undergoes rigorous testing to ensure it meets or exceeds original factory specifications for performance and reliability.