Is Your Oldsmobile Alero Running Rough?
If you’re dealing with a frustrating check engine light, unpredictable stalling, poor fuel mileage, or harsh transmission shifting in your 1999 Alero, the culprit is often a failing Powertrain Control Module (PCM). As the brain of your vehicle, when the PCM starts to go, it can create a cascade of problems that are difficult to diagnose. I’ve seen it hundreds of times in my shop: a customer comes in with a list of strange electrical and performance issues, and after checking the basics, the trail leads directly back to a faulty engine computer.
The Direct Solution: A VIN-Programmed PCM
Forget expensive diagnostic fees and a mandatory trip to the dealership. This Powertrain Control Module is the straightforward, reliable solution you need. We take all the guesswork and hassle out of the repair. When you order, simply provide us with your vehicle’s VIN, and our technicians will program the module with the latest GM-certified software specifically for your car. This ensures perfect communication between the engine, transmission, and all related systems right out of the box.
Expert Pro Tip from a 20-Year Technician
Before you install your new PCM, take a moment to closely inspect the wiring harness connectors. Over the decades, the plastic can become brittle and the metal pins inside can get corroded or even slightly bent. A poor connection here can mimic the symptoms of a bad module or even damage your new part. Use a small pick and some electrical contact cleaner to ensure every pin is straight, clean, and ready to make a solid connection. This five-minute check can save you hours of headaches.
Symptoms of a Failing 1999 Alero Powertrain Control Module
A faulty PCM can manifest in many ways. If you’re experiencing any of the following, it’s a strong indicator that your module needs replacement:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Engine stalling or cutting out while driving
- ✔ No-start or hard-start conditions
- ✔ Noticeable decrease in fuel economy
- ✔ Erratic or harsh automatic transmission shifting
- ✔ Failure to pass emissions testing
- ✔ Communication error codes with a scan tool
Simple, Plug-and-Play Installation
We’ve made this repair as simple as possible. Because the module arrives programmed to your VIN, you won’t need any special scan tools or a trip to the dealer for additional programming. Just follow these simple steps.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the Old PCM: On the 1999 Alero, the PCM is typically located in the center of the dash, accessible from the passenger side footwell. On other models, it may be in the engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Then, unbolt it from its mounting bracket.
- Install the New Module: Bolt the new PCM into place and securely reconnect the wiring harnesses. Ensure they click into place.
- Reconnect Battery: Re-attach the negative battery terminal. The vehicle is now ready to start. A security relearn procedure may be required, which typically involves turning the key to the ‘ON’ position for 10-15 minutes.
Guaranteed Compatibility
This module is a direct replacement for a wide range of GM vehicles from the late 1990s. It is fully compatible with service part numbers 09356741, 16236757, 9356741, 9357034, 9357440, and 9366314. Please verify the part number on your original module or contact us with your VIN to confirm fitment for models like the Grand Am, Century, Regal, Grand Prix, Lumina, Monte Carlo, and more.