Restore Peak Performance to Your GM 3.6L Engine
Is your 2010-2011 Buick LaCrosse, Chevrolet Camaro, or another GM vehicle with the 3.6L engine suddenly stalling, shifting erratically, or refusing to start? These are classic signs of a failing Engine Control Module (ECM), the computer that serves as your vehicle’s brain. A faulty ECM can cripple your car’s performance, fuel economy, and reliability. This isn’t just an inconvenience; it’s a critical failure that needs a dependable solution. Driving with a compromised ECM can lead to further engine damage or leave you stranded.
We offer a straightforward, reliable fix. This ECM, part number 12636355, is professionally flashed with the very latest official GM software updates. We program it specifically to your vehicle’s Vehicle Identification Number (VIN) before it ships. This ensures perfect communication between the module and your car’s complex systems, restoring the smooth operation you expect from your vehicle.
Is Your GM 3.6L Engine Showing These Signs?
- ✔ Unexplained check engine light that won’t go away.
- ✔ Engine stalling or cutting out while driving.
- ✔ Complete no-start condition where the engine cranks but won’t fire up.
- ✔ Noticeable decrease in fuel mileage.
- ✔ Harsh or inconsistent automatic transmission shifting.
- ✔ Diagnostic Trouble Codes (DTCs) stored, such as P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
Case Study: A Tricky Diagnosis
A customer brought in a 2011 GMC Acadia with the 3.6L engine—a vehicle that uses this exact ECM. The complaint was an intermittent no-start, but only on hot summer days after it had been driven for a while. Every time it got to my bay, it would start right up. After checking all the usual suspects (battery, starter, fuel pump), I decided to heat the ECM carefully with a heat gun while monitoring data. Sure enough, once the module reached a certain temperature, communication would drop out completely. The internal processor was failing under heat stress. A new, properly programmed ECM solved the problem permanently. This is a common failure mode I’ve seen dozens of times on these platforms.
A Straightforward Guide to Installation
Replacing your 2010-2011 LaCrosse ECM is a manageable job for a DIY enthusiast. For LaCrosse and Camaro owners, please note the special immobilizer service detailed below to ensure a true plug-and-play experience.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- Locate the ECM: On the LaCrosse, it’s typically found in the engine compartment on the driver’s side (LH). On other models like the Traverse or Acadia, it’s often behind the fan shroud. Consult a service manual for your specific vehicle if you’re unsure.
- Disconnect Connectors: Carefully unplug the electrical wiring harnesses from the old ECM. These connectors have locking tabs that must be released before pulling. Do not force them.
- Remove the Old Module: Unbolt the old ECM from its mounting bracket. Keep the hardware, as you will need it to install the new unit.
- Install the New ECM: Mount your new, pre-programmed ECM onto the bracket and secure it with the original hardware.
- Reconnect Everything: Plug the wiring harnesses firmly into the new module until they click into place. Reconnect the negative battery terminal.
- Immobilizer Relearn (If Applicable): For most vehicles, the car is ready to start. For vehicles where immobilizer data was not transferred, a security relearn procedure may be required.
Important Note for LaCrosse & Camaro Owners
To ensure your vehicle starts and runs without any security-related issues, the immobilizer information from your original ECM must be transferred to this new one. This is a service we provide. After your purchase, we will contact you with instructions on how to send us your old module. This step makes the new ECM fully plug-and-play, saving you from a costly trip to the dealership for security programming.
Verified Vehicle Compatibility
This module is a direct-fit replacement for the following vehicles equipped with the 3.6L engine. It is compatible with part numbers 19300015, 19300014, 12617230, 12636355, and 12635019.
- Buick Allure: 2010 (LH engine compartment)
- Buick Enclave: 2010-2011 (behind fan shroud)
- Buick LaCrosse: 2010-2011 (LH engine compartment)
- Cadillac CTS: 2010-2011 (RH front engine compartment)
- Cadillac STS: 2010-2011 (RH engine)
- Chevrolet Camaro: 2010-2011
- Chevrolet Traverse: 2010-2011 (behind fan shroud)
- GMC Acadia: 2010-2011 (behind fan shroud)
- Saturn Outlook: 2010 (behind fan shroud)
Frequently Asked Questions
Important Note for LaCrosse & Camaro Owners
To ensure your vehicle starts and runs without any security-related issues, the immobilizer information from your original ECM must be transferred to this new one. This is a service we provide. After your purchase, we will contact you with instructions on how to send us your old module. This step makes the new ECM fully plug-and-play, saving you from a costly trip to the dealership for security programming.