Is Your Buick LaCrosse Running Rough or Not Starting?
If your 2010-2011 Buick LaCrosse is experiencing baffling electrical issues, a persistent Check Engine light, poor performance, or even a no-start condition, a failing Engine Control Module (ECM) is a very likely culprit. The ECM is the central computer of your vehicle, responsible for managing everything from fuel injection and ignition timing to transmission shifting and emissions control. When it begins to fail, it can create a cascade of problems that are often difficult to diagnose, leading to frustrating and expensive trips to the mechanic.
This isn’t just a replacement part; it’s a direct solution to get your vehicle back to factory-spec operation. We provide a genuine GM Engine Control Module, part number 12636355, that comes professionally programmed with the latest official GM software updates. This critical programming service is performed using your vehicle’s unique Vehicle Identification Number (VIN), ensuring that the module is a perfect match for your car’s specific configuration and options.
From the Diagnostic Bay
We recently had a 2011 Buick LaCrosse 3.6L towed in with a classic case of ECM failure. The owner had been chasing ghosts for months. The car would randomly stall at traffic lights, the transmission would shift erratically, and the dash was lit up like a Christmas tree with various warning lights. Multiple shops had replaced sensors and spark plugs to no avail. When we hooked up our diagnostic tool, we found multiple communication error codes (U-codes) pointing to a breakdown in the CAN bus network. This is a tell-tale sign that the main controller, the ECM, is failing internally. After confirming power and ground to the module were good, we installed one of our VIN-programmed ECMs. The difference was immediate. All communication was restored, the engine ran smoothly, and after a final test drive, the car was performing exactly as it should. It’s a perfect example of how the right, correctly programmed part can solve a complex problem efficiently.
Key Symptoms of a Failing 2010-2011 LaCrosse ECM
A faulty engine computer can manifest in numerous ways. If you’re noticing any of the following issues, it’s time to consider your ECM as the source of the problem:
- ✔ Check Engine Light: Your check engine light is on, and you may have trouble codes related to module communication (U-codes) or internal processor faults (P06xx codes).
- ✔ No-Start or Hard Starting: The engine cranks but refuses to start, or takes an unusually long time to fire up. This can be due to the ECM not commanding the fuel pump or ignition coils correctly.
- ✔ Poor Engine Performance: You may experience a significant loss of power, rough idling, engine misfires, or hesitation during acceleration.
- ✔ Reduced Fuel Economy: An ECM that isn’t calculating the air-fuel mixture correctly can cause your vehicle to consume much more gasoline than usual.
- ✔ Transmission Problems: The ECM works closely with the Transmission Control Module (TCM). A failing ECM can cause harsh shifting, delayed engagement, or the transmission getting stuck in one gear (limp mode).
- ✔ Intermittent Stalling: The vehicle may stall for no apparent reason, either while driving or when stopped at idle, and may or may not restart immediately.
The Critical VIN Programming Process
You can’t simply take an ECM from another vehicle and plug it into yours. Modern vehicles have sophisticated anti-theft systems and specific software calibrations. Our service eliminates the guesswork and the need for expensive dealership programming. When you place your order, you provide us with your 17-digit VIN. We use this to load the exact, most current GM-approved software for your vehicle’s engine, transmission, and options package directly onto the module.
Important Note for LaCrosse and Camaro Owners: Due to the specific immobilizer (anti-theft) system used in the 2010-2011 LaCrosse and Camaro, a simple VIN flash is not enough to make the module plug-and-play. The unique immobilizer key data must be transferred from your original ECM to the replacement one. For these models, you will need to send us your old module. We will expertly read the security information and write it to the new unit, making it a true plug-and-play solution that will allow your car to start and run without any further security procedures. We will contact you with shipping instructions for your old module after your purchase is complete.
Guaranteed Fitment and Compatibility
This Engine Control Module is a direct-fit replacement for a wide range of GM vehicles equipped with the 3.6L V6 engine. Please verify that your vehicle is listed below and that your original part number is on our compatibility list.
This part is a direct replacement for the following part numbers:
- 19300015
- 19300014
- 12617230
- 12636355
- 12635019
This part will fit the following vehicles with the 3.6L engine option:
- 2010-2011 Buick LaCrosse
- 2010-2011 Chevrolet Traverse
- 2010-2011 Cadillac CTS
- 2010-2011 Chevrolet Camaro
- 2010 Saturn Outlook
- 2010 Buick Allure
- 2010-2011 Buick Enclave
- 2010-2011 GMC Acadia
- 2010-2011 Cadillac STS
Frequently Asked Questions
Do I need to do any programming myself?
No. We handle all the necessary programming for you. For most compatible vehicles, the module will be ready for installation upon arrival. For the 2010-2011 LaCrosse and Camaro, you will need to send us your original ECM so we can transfer the immobilizer data, making the replacement fully plug-and-play.
What information do you need from me?
We require your vehicle’s 17-digit Vehicle Identification Number (VIN) to ensure we load the correct software for your specific car. Please provide this during or after checkout.
Where is the ECM located on my 2011 LaCrosse?
On the 2010-2011 Buick LaCrosse, the Electronic Control Module is located in the engine compartment on the left-hand (driver’s) side.
What happens if I install this in my Camaro without sending you my old ECM?
The vehicle will not start. The immobilizer system will not recognize the new ECM, and it will prevent the engine from starting as an anti-theft measure. Transferring the data from your old module is a required step for these specific models.
Is this a used part?
This is a high-quality, tested, and verified component guaranteed to function correctly. Each module is inspected and then programmed with the latest software for your vehicle to ensure reliable performance.