Restore Peak Performance to Your GM Vehicle
If you’re dealing with frustrating issues like intermittent stalling, poor fuel economy, harsh transmission shifts, or a dreaded no-start condition, the problem often traces back to a failing Powertrain Control Module (PCM). As a technician with over two decades of experience under the hood, I’ve seen firsthand how a faulty PCM can mimic a dozen other problems, leading to wasted time and money on unnecessary parts. This isn’t just a component; it’s the central computer of your vehicle, and when it falters, everything it controls suffers. This replacement PCM, service number 09356741, is the definitive solution to restore your vehicle’s reliability and drivability.
Case Study: A Tricky Diagnosis
I remember a 1998 Buick LeSabre that came into the shop with a complaint of random stalling at traffic lights and a transmission that seemed to have a mind of its own. The owner had already replaced the fuel pump and a few sensors with no luck. The scan tool showed some odd communication errors but nothing consistent. After checking the power and ground feeds to the PCM, we found they were solid. On a hunch, we connected a lab scope and saw the 5-volt reference signal dropping out intermittently. This is a classic sign of an internal PCM failure. We installed a VIN-programmed module just like this one, and the car ran perfectly. It’s a textbook example of how a failing 1999 Alero Powertrain Module can create ghost-like symptoms that defy simple diagnosis.
Common Signs of a Failing PCM
A failing computer can cause a wide range of symptoms. If your vehicle is experiencing any of the following, a faulty PCM could be the culprit. Keep an eye out for these common diagnostic trouble codes (DTCs) as well, especially P0601 or P0605, which point directly to an internal module failure.
- ✔ Check Engine Light is illuminated with communication-related codes.
- ✔ Vehicle will not start or is very difficult to start.
- ✔ Erratic or harsh automatic transmission shifting.
- ✔ A noticeable drop in fuel efficiency.
- ✔ Engine stalling or misfiring for no apparent reason.
- ✔ Failure to pass an emissions inspection.
The Importance of VIN-Specific Programming
Why is providing your Vehicle Identification Number (VIN) so critical? Unlike a simple sensor, this 1999 Alero Powertrain Module must be precisely calibrated to your vehicle’s specific configuration. Our process ensures this module arrives with the latest GM software updates loaded directly to it. This programming configures essential parameters like fuel delivery tables, transmission shift strategies, and the vehicle’s anti-theft system (VATS/Passlock). By programming it before shipment, we eliminate the need for an expensive trip to the dealership, making this a true plug-and-play solution.
A Straightforward Guide to Installation
Replacing your PCM is a job most DIYers can handle with basic tools. Follow these steps to get your vehicle back on the road quickly.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait about 10 minutes to ensure all systems are fully powered down.
- Locate the PCM: On many of these GM models, the PCM is located in the engine bay, often inside the air filter box, or on the driver’s side of the center console behind a trim panel. Consult a repair manual for your specific vehicle if you’re unsure.
- Disconnect the Connectors: Carefully unlatch and remove the electrical wiring harnesses from the old module. Inspect the connectors for any signs of corrosion or damage and clean them if necessary.
- Swap the Modules: Unbolt the old PCM from its mounting bracket and set it aside. Secure the new module in its place.
- Reconnect Everything: Firmly plug the wiring harnesses into the new PCM until they click into place. Reconnect the negative battery terminal.
- Final Check: Start the vehicle. It may take a few seconds to fire up as the system initializes. Let it run for a few minutes and check for any warning lights. A security relearn procedure may be required on some models, which typically involves cycling the key.
Verified Vehicle Compatibility
This module is a direct replacement for service numbers 09356741, 16236757, 9357034, 9357440, and 9366314. It is guaranteed to fit the following vehicles:
- 1999 Alero (3.4L)
- 1998-1999 Grand Am (3.1L, 3.4L)
- 1998 Achieva (3.1L)
- 1998 Bonneville
- 1998 Camaro (3.8L)
- 1998 Century (3.1L)
- 1998-1999 Cutlass
- 1998 Eighty Eight
- 1998 Firebird (3.8L)
- 1998 Grand Prix
- 1998 Intrigue
- 1998 LeSabre (3.8L)
- 1998 Lumina Car
- 1998 Malibu (3.1L)
- 1998 Monte Carlo
- 1998 Park Avenue (3.8L)
- 1998 Regal
- 1998 Riviera (3.8L)
- 1998 Silhouette
- 1998 Skylark (3.1L)
- 1998 Trans Sport
- 1998 Venture (3.4L)
Note: Please ensure your existing module’s service number is listed for guaranteed compatibility.
Frequently Asked Questions
Frequently Asked Questions
Do I need to have this programmed by a dealer after I receive it?
No. We program the module to your vehicle’s VIN before we ship it. It will arrive ready for installation, saving you the time and expense of a dealership visit.
What information do you need from me?
After you complete your purchase, you will need to provide us with your vehicle’s 17-digit VIN. This is essential for us to load the correct GM software for your car.
Is any other procedure needed after installation?
In some cases, a simple security relearn procedure (often called a Passlock or VATS relearn) may be necessary. This can typically be done without special tools and involves a sequence of key turns. Instructions are readily available online for your specific model.
Will this fix my car’s specific problem?
This 1999 Alero Powertrain Module is a direct solution for a failed PCM. While it resolves many common engine and transmission issues, we always recommend a proper diagnosis to confirm the PCM is the root cause of your problem before ordering.
Where can I find my VIN?
Your VIN can be found on your vehicle’s registration, insurance card, or on a metal plate on the driver’s side of the dashboard, visible through the windshield.