Is Your Buick Regal Experiencing Frustrating Engine Problems?
As a technician with over two decades under the hood, I’ve seen my share of 2003-2004 Buick Regals. They’re solid cars, powered by the legendary 3.8L V6, but even the best vehicles have their weak points. If you’re dealing with baffling issues like intermittent stalling, erratic shifting, a persistent check engine light, or a complete no-start condition, the culprit is often the very brain of your engine: the Powertrain Control Module (PCM).
A failing PCM can turn a reliable daily driver into a source of constant stress. You’re not just buying a part; you’re buying a solution to get your trusted car back on the road, running smoothly and efficiently. This isn’t just another component; it’s the key to restoring your vehicle’s performance and your peace of mind.
Why This 2003-2004 Regal PCM is Your Best Solution
Forget the hassle and expense of a dealership visit. This replacement Powertrain Control Module, service number 89017735 (also compatible with 12583826), is delivered to your door fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We handle the complex part so you don’t have to. We flash it with the latest official GM software updates, which often correct drivability issues the original factory programming had. This ensures optimal performance and compatibility right out of the box.
A Technician’s Real-World Experience
“A customer’s 2003 Regal came into my shop last month with a harsh 1-2 shift and a random P0300 misfire code that we couldn’t pin down. He had already replaced plugs, wires, and a coil pack. After confirming fuel pressure and sensor data were good, we suspected the PCM. The original module was sending erratic signals to the transmission solenoids. We installed one of our pre-programmed units, and the car immediately shifted like new and the misfire code never returned. It’s a classic case where the driver feels a transmission problem, but the root cause is electronic.”
Common Symptoms of a Failing PCM:
- ✔ Unexplained Check Engine Light (CEL) illumination
- ✔ Engine stalling or cutting out while driving
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Poor fuel economy
- ✔ No-start or difficult starting conditions
- ✔ Communication errors with diagnostic scan tools
- ✔ False sensor codes being stored in memory
Plug-and-Play Installation: No Dealer Visit Required
Installing your new 2003-2004 Regal PCM is a straightforward process you can do in your own driveway. All you need are basic hand tools.
- Safety First: Disconnect the negative terminal from your car’s battery and secure it away from the post.
- Locate the PCM: On your Regal, the PCM is located in the air filter housing assembly in the left-hand (driver’s side) of the engine compartment.
- Remove the Old Unit: Carefully unclip and remove the plastic cover, then disconnect the electrical harness connectors. They have locking tabs, so be gentle. Unbolt the module from its mounting bracket.
- Install the New PCM: Seat the new, pre-programmed module in the housing, bolt it down securely, and firmly reconnect the wiring harnesses until they click into place.
- Final Step: Reconnect 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. Your vehicle’s manual may have specific instructions.
Guaranteed Fitment
This module is a direct-fit replacement for vehicles requiring service number 89017735 or 12583826. It is compatible with the following models:
- 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 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 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)
IMPORTANT: After purchase, please provide us with your VIN. This is essential for us to program the module correctly for your specific vehicle before shipment. Restore your car’s reliability and order with confidence today!