Restore Peak Performance to Your 3.8L Engine
Is your 2006-2008 Pontiac Grand Prix, Buick LaCrosse, or Lucerne suffering from frustrating and unpredictable issues? Problems like a persistent check engine light, stalling, rough idling, or a complete no-start condition often point to a failing Powertrain Control Module (PCM). As the central computer of your vehicle, the PCM is responsible for managing everything from fuel injection and spark timing to transmission shifting and emissions controls. When it fails, the symptoms can be widespread and difficult to diagnose. This replacement PCM, part number 12619810, is the definitive solution to restore your vehicle’s reliability and drivability.
This isn’t just a generic, off-the-shelf part. We take the guesswork out of the repair by pre-programming the module specifically for your car using your vehicle’s unique Vehicle Identification Number (VIN). This critical step ensures that the PCM has the correct software and calibrations for your engine, transmission, and factory-installed options. It arrives loaded with the latest GM software updates, which can resolve common drivability issues and improve overall performance and efficiency. By providing your VIN upon purchase, you receive a module that is tailored to your exact vehicle, simplifying the installation process and ensuring a successful repair.
From the Diagnostic Bay
We had a 2007 Buick Lucerne come into the shop with a classic ‘no-start’ complaint. The owner had already replaced the battery and alternator, and another shop had even suggested a new fuel pump. The scanner wouldn’t communicate with the engine computer at all, which is a big red flag. Before condemning the expensive module, we checked the basics. We found the main ground wire for the PCM, located near the transmission bell housing, was corroded and barely making contact. After cleaning the connection point and tightening the ground, the car fired right up. It’s a powerful reminder: while a failed PCM can cause a no-communication issue, always verify power and ground connections to the module before ordering a replacement. A few minutes with a multimeter can save you hundreds of dollars.
Your Solution for a Faulty 2006-2008 Grand Prix PCM
A failing PCM can manifest in numerous ways, often mimicking other component failures. If you’re experiencing a combination of the symptoms below, there’s a strong likelihood that your vehicle’s main computer is the culprit. Replacing it with our VIN-programmed unit is the most effective way to get your car running properly again. This module directly interchanges with several part numbers, including 12600930, 12616866, 12619810, and 12509307, ensuring wide compatibility.
Common Symptoms of a Failing PCM:
- ✔ Check Engine Light: The light is on, and you may have codes related to module communication, sensor circuits, or processor faults.
- ✔ No-Start or Hard Starting: The engine cranks but refuses to start, or takes an excessively long time to fire up.
- ✔ Engine Stalling: The vehicle stalls unexpectedly while driving or when coming to a stop.
- ✔ Poor Performance & Fuel Economy: Noticeable loss of power, hesitation during acceleration, and a sudden drop in gas mileage.
- ✔ Erratic Transmission Shifting: Harsh shifts, delayed engagement, or getting stuck in one gear (limp mode).
- ✔ Intermittent Issues: Problems that appear and disappear, often related to temperature changes.
- ✔ Failed Emissions Test: Inability to pass smog tests due to module-related faults.
Installation & Security Relearn
This PCM is located in the lower part of the air cleaner box, making it reasonably accessible. While the module is programmed to your VIN, your vehicle’s anti-theft system (Passlock/Passkey III) will need to relearn the new PCM’s identity. This is a straightforward procedure that you can perform yourself without any special tools.
Security Relearn Procedure (Typical):
- Install the new PCM and reconnect the battery.
- Turn the key to the ‘ON’ position (do not start the engine).
- Observe the ‘Security’ or ‘Theft’ light on the dashboard. It will likely be flashing or on solid.
- Leave the key in the ‘ON’ position for approximately 10-12 minutes, or until the security light turns off or stops flashing.
- Once the light goes out, turn the key to the ‘OFF’ position for 10 seconds.
- Repeat the process two more times for a total of three 10-minute cycles.
- After the third cycle, the vehicle should start and run normally.
Note: This is a general guide. Please consult a service manual for the exact procedure for your specific model.
Guaranteed Fitment
This Electronic Control Module is a direct fit for the following vehicles equipped with the 3.8L V6 engine:
- Buick Allure: 2006-2009
- Buick LaCrosse: 2006-2009
- Buick Lucerne: 2006-2008
- Pontiac Grand Prix: 2006-2008
Frequently Asked Questions
What is a PCM and what does it do?
The Powertrain Control Module (PCM) is the main computer that controls your vehicle’s engine and transmission. It takes data from sensors all over the vehicle to manage fuel delivery, spark timing, emissions systems, and automatic transmission shift points to ensure optimal performance and efficiency.
Is this part truly plug-and-play?
It is very close. Because we program the module to your specific VIN, it eliminates the need for expensive dealer programming. However, you will need to perform the vehicle’s security relearn procedure after installation, which syncs the new PCM with your car’s anti-theft system. This procedure is simple and does not require special tools.
How do I provide you with my VIN?
After you complete your purchase, you will receive instructions on how to send us your vehicle’s 17-digit VIN. We cannot ship your order until we receive this information, as it is essential for correct programming.
Will this PCM fix my check engine light?
If the check engine light is caused by an internal failure of the original PCM, then yes, this part will solve the problem. However, if the light is on due to a faulty sensor, bad wiring, or another mechanical issue, you will still need to diagnose and repair that separate problem.
Where is the PCM located on my 2007 Grand Prix?
On the 2006-2008 Pontiac Grand Prix and other compatible models, the PCM is located inside the lower housing of the engine’s air cleaner box. You will need to remove the top of the air filter box and the air filter to access it.
Do I need to have my old PCM on hand?
No, there is no core charge or need to return your old module. We only require your vehicle’s VIN to program the new unit before shipping it to you.