Is Your 2003 Impala Running Rough, Stalling, or Showing a Check Engine Light?
If you’re dealing with frustrating engine problems like unpredictable stalling, a rough idle, poor fuel mileage, or a persistent check engine light, the root cause is often a failing Powertrain Control Module (PCM). As the central computer for your vehicle, a faulty PCM can create a cascade of issues that make your car unreliable and stressful to drive. I’ve seen it hundreds of times in my shop: a driver comes in, frustrated that they can’t trust their car anymore, and the diagnostic codes all point to a communication breakdown originating from the engine computer.
The Reliable, Pre-Programmed Solution for Your GM Vehicle
This isn’t just a replacement part; it’s a complete solution. We are providing a high-quality Powertrain Control Module, service number 89017735 (also compatible with 12583826), that is professionally programmed to your car’s specific Vehicle Identification Number (VIN). This critical step ensures that the module communicates perfectly with your engine, transmission, and all other onboard systems. We load the latest, most stable software updates from GM, which often correct original factory flaws and improve overall performance and drivability.
Real-World Diagnosis: “A customer’s 2003 Bonneville with the 3.8L V6 came into my bay last month with intermittent stalling and no communication with my professional scan tool. After verifying all power and ground circuits to the module were solid, we identified the internal failure of the PCM. Swapping in a VIN-programmed module like this one had the car running smoothly in under 30 minutes. It’s a common failure point on these otherwise very reliable GM platforms.”
Why Choose Our 2003 Impala Powertrain Control Module?
Getting your car back to factory-spec performance is our priority. This module is the definitive fix for a wide range of electronic and performance issues.
- ✔ Eliminate Common Symptoms: Puts an end to issues like engine stumbling, harsh or failed shifting, inaccurate fuel gauge readings, and false anti-theft system alerts.
- ✔ VIN-Programmed for Your Car: We handle all the programming before we ship. This means no expensive trips to the dealership for flashing or configuration. It arrives ready to install.
- ✔ Latest GM Software: Your module comes loaded with the newest calibrations, ensuring optimal engine performance, fuel efficiency, and transmission shifting.
- ✔ Restores Communication: Fixes diagnostic trouble codes (DTCs) related to module communication errors, allowing for proper vehicle diagnostics in the future.
Plug-and-Play Installation: No Dealer Visit Required
You can perform this replacement right in your own driveway with basic hand tools. Our pre-programming service makes the process straightforward.
- Safety First: Disconnect the negative terminal from your car’s battery and wait at least 15 minutes to allow all system capacitors to discharge.
- Locate the PCM: On your 2003 Impala, the PCM is located in the air filter housing on the driver’s side (LH) of the engine compartment.
- Disconnect Connectors: Carefully unclip and remove the electrical wiring harnesses from the old module. Inspect the pins for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket or housing.
- Install the New Module: Secure the new PCM in place and firmly reconnect the wiring harnesses. You should hear a ‘click’ as they lock.
- Reconnect Battery: Reattach the negative battery terminal. The vehicle may need to complete a security relearn procedure, which typically involves turning the key to the ‘ON’ position for 10-15 minutes.
Expert Pro Tip: Check Your Grounds Before Installation
Before installing your new module, take a moment to inspect and clean the main engine-to-chassis ground strap. On many of these GM vehicles, a corroded or loose ground can cause voltage irregularities that mimic PCM failure and can even damage the new component. A simple wire brush cleaning at the connection points can save you a major headache.
Guaranteed Fitment
This module is a direct-fit replacement for several GM models. Please verify your vehicle and options below. The service ID number is printed on the label of your original module.
- 2003 Chevrolet Impala: Electronic Control Module; (LH engine compartment), 3.8L, ID 12583826 or 89017735
- 2003 Chevrolet Monte Carlo: Electronic Control Module; (LH engine compartment), 3.8L, ID 12583826
- 2003-2004 Buick Regal: Electronic Control Module; (LH engine compartment)
- 2003 Buick LeSabre: Electronic Control Module; (LH engine compartment), ID 12583826
- 2003-2004 Buick Park Avenue: Electronic Control Module; (LH front engine compartment)
- 2003 Pontiac Bonneville: Electronic Control Module; (LH engine compartment), ID 12583826
- 2003 Pontiac Grand Prix: Electronic Control Module; (LH front engine compartment), 3.8L, ID 12583826
Don’t let a faulty computer keep you off the road. Order your pre-programmed 2003 Impala Powertrain Control Module today and restore your vehicle’s reliability and performance with confidence.