Is Your GM Vehicle Running Rough? Get a Reliable, Programmed Solution.
As a technician with over two decades of experience under the hood, I’ve seen countless drivers frustrated by persistent check engine lights, poor fuel mileage, and erratic engine behavior. Often, the culprit is a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. If you’re dealing with stalling, hard starts, or transmission shifting problems in your 1999 Oldsmobile Alero or another compatible GM model, you’ve found the definitive fix. This isn’t just a replacement part; it’s a fully programmed, plug-and-play solution designed to restore your vehicle’s performance and reliability.
We take the guesswork and extra expense out of the equation. Before this module ships, we flash it with the latest official GM software updates, tailored specifically to your car using the VIN you provide. This means no costly trips to the dealership for programming. You get a direct-fit 1999 Alero Powertrain Control Module that’s ready for installation right out of the box, ensuring all engine and transmission parameters are set exactly to factory specifications for optimal operation.
A Technician’s Notebook: The Phantom Misfire
A customer brought in a ’99 Grand Am with the 3.4L V6, complaining of a random, intermittent misfire that no one could solve. They had already replaced plugs, wires, and the ignition coil pack. The scan tool showed random misfire codes, but live data looked normal most of the time. From experience, I know that the driver circuits inside these older PCMs can weaken over time, especially after thousands of heat cycles. Instead of sending a clean signal to the injectors or coils, a failing PCM can send a weak or erratic one, causing a misfire that doesn’t set a specific cylinder code. We installed a correctly programmed PCM, and the problem vanished instantly. It’s a classic case where the root cause wasn’t a mechanical part, but the computer controlling it.
Common Signs of a Failing PCM
If your vehicle’s computer is on its way out, you’ll likely notice one or more of these issues. A new 1999 Alero Powertrain Control Module can resolve these problems.
- ✔ Check Engine Light is illuminated with codes like P0601, P0602, or P0605 (Internal Control Module Errors).
- ✔ The engine cranks but refuses to start.
- ✔ Rough idling, stalling, or hesitation during acceleration.
- ✔ A noticeable drop in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to pass an emissions inspection.
- ✔ Communication errors with your scan tool.
A Straightforward Guide to Your PCM Installation
Installing your new PCM is a manageable job for a DIYer with basic tools. Following these steps will help ensure a smooth process. Remember, on many GM vehicles, a security relearn procedure is required after installation.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most of these vehicles, the PCM is located in the engine compartment, often inside the air filter housing or on the firewall. On some models like the Alero/Grand Am, it’s under the left-hand side of the dash. Consult a repair manual for your specific vehicle.
- Disconnect the Connectors: Carefully unclip the wiring harness connectors from the old module. Inspect the terminals for any corrosion or damage before proceeding.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt your new, pre-programmed PCM into place. Reconnect the wiring harnesses, ensuring they click securely into place.
- Reconnect the Battery: Reattach the negative battery terminal.
- Perform Security Relearn: Most GM vehicles of this era require a security relearn (often called a Passlock or Passkey relearn) to allow the car to start. This procedure typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Search for the specific procedure for your model to be sure.
Verified Vehicle Compatibility
This module is a direct replacement for service number 09356741 and is also compatible with 16236757, 9357034, 9357440, and 9366314. It is guaranteed to fit the following vehicles:
- ACHIEVA 1998 (3.1L)
- ALERO 1999 (3.4L)
- BONNEVILLE 1998
- CAMARO 1998 (3.8L)
- CENTURY 1998 (3.1L)
- CUTLASS 1998-1999
- EIGHTY EIGHT 1998
- FIREBIRD 1998 (3.8L)
- GRAND AM 1998-1999 (3.1L, 3.4L)
- GRAND PRIX 1998
- INTRIGUE 1998
- LESABRE 1998 (3.8L)
- LUMINA CAR 1998
- MALIBU 1998 (3.1L)
- MONTE CARLO 1998
- PARK AVENUE 1998 (3.8L)
- REGAL 1998
- RIVIERA 1998 (3.8L)
- SILHOUETTE 1998
- SKYLARK 1998 (3.1L)
- TRANS SPORT 1998
- VENTURE 1998 (3.4L)
This 1999 Alero Powertrain Control Module is your key to resolving frustrating electronic issues and getting your car back to running the way it should. Order today and experience the difference a properly functioning, correctly programmed PCM makes.
How do I provide my VIN for programming?
How do I provide my VIN for programming?
After you complete your purchase, you will need to send us your vehicle’s 17-digit VIN (Vehicle Identification Number). You can typically find this on your dashboard (visible through the windshield) or on the driver’s side door jamb sticker. We cannot ship your module until we receive the VIN.
Is this part difficult to install?
For someone with basic mechanical skills, the physical installation is straightforward. The most critical part is performing the security relearn procedure after the new PCM is installed. This procedure is simple but must be followed exactly for the vehicle to start.
Will this fix my transmission problems?
In many GM vehicles, the PCM also controls the automatic transmission. If your shifting issues are caused by faulty electronic signals from a failing module, then yes, this part is very likely to solve the problem. It restores the correct communication between the engine and transmission.
Does this module come with a warranty?
Yes, all our modules come with a warranty that covers any defects in the part itself. Please refer to the warranty section of the listing for specific details and duration.
What if my part number isn’t an exact match but my car is on the list?
This module replaces several different service numbers (09356741, 16236757, 9357034, etc.). As long as your vehicle model and year are on our compatibility list, this module will function correctly once programmed with your VIN, even if the number on your old part is different.