Is your GM truck, SUV, or performance car suffering from erratic behavior, a persistent check engine light, or a no-start condition? These are classic signs of a failing Engine Control Module (ECM), the central computer that manages your vehicle’s engine performance, fuel economy, and emissions. A faulty ECM can lead to frustrating and costly diagnostic chases. This direct-replacement ECM is the definitive solution to restore your vehicle’s factory performance and reliability.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. Each module is professionally programmed with the latest official GM software updates specifically for your vehicle. By providing us with your Vehicle Identification Number (VIN) after your purchase, we ensure the module you receive is a perfect match, eliminating the need for expensive programming services at a dealership. This unit is a direct replacement for part numbers 12633055 and 12633238, covering a wide range of popular GM models.
From the Diagnostic Bay
We recently had a 2012 GMC Sierra 1500 in the shop with a persistent P0300 random misfire code that the owner had been chasing for months. He had already replaced spark plugs, ignition coils, and even injectors with no success. After connecting our diagnostic tools, we found that the injector driver circuit within the original ECM was failing intermittently. Instead of more guesswork, we installed a VIN-programmed module like this one. The misfire was gone instantly, and the truck ran smoother than ever. It’s a reminder that the ECM is often the root cause of the most elusive engine problems.
Restore Peak Performance with a Programmed GM ECM 12633055
Don’t let a failing engine computer keep you off the road. This module is meticulously tested to meet or exceed original equipment standards. Once programmed to your VIN, it restores crucial functions like fuel mixture, ignition timing, and transmission shift points to their optimal settings. The result is a smoother-running engine, restored fuel efficiency, and the peace of mind that comes from a reliable vehicle. Installation is straightforward for any competent mechanic or experienced DIYer, and in most cases, only a simple security relearn procedure is required after the physical installation.
Common Symptoms of a Failing Engine Computer
- ✔ Persistent Check Engine Light (CEL) with various fault codes.
- ✔ Engine stalling, stumbling, or misfiring for no apparent reason.
- ✔ A noticeable and unexplained decrease in fuel economy.
- ✔ Harsh or erratic shifting from the automatic transmission.
- ✔ Intermittent no-start condition where the engine cranks but won’t fire up.
- ✔ Loss of communication with the ECM when using a diagnostic scan tool.
- ✔ Performance issues like hesitation or lack of power.
Ordering this GM ECM 12633055 is the most effective step toward resolving these issues and getting your vehicle back to its peak operational state. Ensure you provide your VIN so we can deliver a true plug-and-play solution tailored to your exact vehicle.
Frequently Asked Questions
Is this ECM ready to install when it arrives?
Yes, this module comes fully programmed to your vehicle’s specific VIN. For many GM vehicles, you may need to perform a simple security relearn procedure (often called a Passlock or anti-theft relearn), which can typically be done without special tools. Instructions are widely available online for this process.
How do I provide my VIN?
After you complete your purchase, please send us a message containing your full 17-digit Vehicle Identification Number. We cannot program and ship your part without it.
Will this fix my vehicle’s problem for sure?
This part is a guaranteed fix for a faulty ECM. However, it’s crucial that your vehicle has been properly diagnosed. This module will not fix problems related to other faulty sensors, wiring, or mechanical components.
My original part number is 12633238. Will this work?
Absolutely. This ECM is a direct, compatible replacement for both part numbers 12633055 and 12633238, covering all intended applications.
What vehicles does this GM ECM 12633055 fit?
This module fits a very wide range of GM vehicles, including many model years of the Silverado, Sierra, Yukon, Tahoe, Suburban, Escalade, Camaro, Corvette, and Express/Savana vans. Please refer to the detailed fitment list on this page to confirm compatibility with your specific model and engine.