Is Your Oldsmobile Alero Running Rough? Get a Reliable, Pre-Programmed Solution.
If you’re dealing with a frustrating check engine light, unpredictable stalling, poor fuel economy, or a no-start condition in your 1999 Alero, a failing Powertrain Control Module (PCM) is often the culprit. As the central computer for your engine, its proper function is critical. This isn’t just a replacement part; it’s a direct-fit, fully programmed solution designed to restore your vehicle’s performance and reliability right out of the box.
The Easiest Way to Replace Your PCM
Forget expensive dealership visits and programming fees. We take the hassle out of the repair. Simply provide us with your vehicle’s VIN (Vehicle Identification Number) during checkout, and our technicians will flash this module with the latest, most stable GM software specific to your car. This ensures perfect communication between the PCM and all other vehicle systems, just as the factory intended.
“A customer’s Grand Am came in last week with these exact symptoms…”
The owner of a ’99 Grand Am (which uses this same PCM) was at his wit’s end. He’d replaced the fuel pump and crank sensor trying to chase down an intermittent stalling issue that left him stranded twice. When we got it in the shop, a quick check with a multimeter at the PCM connectors showed we had good power and ground inputs, but the injector pulse would randomly drop out. This told me the problem was internal to the module itself. A failing capacitor on the main board was overheating. We installed one of our pre-programmed modules, and the car has run flawlessly ever since. It’s a classic failure I’ve seen dozens of times on these GM platforms.
Common Symptoms of a Failing 1999 Alero Powertrain Control Module
A faulty PCM can manifest in numerous ways. If you’re experiencing any of the following, it’s time to inspect your engine’s computer:
- ✔ Persistent Check Engine Light (CEL) with various trouble codes
- ✔ Engine stalling or shutting off while driving
- ✔ Difficulty starting the engine or a complete no-start
- ✔ Noticeable decrease in fuel efficiency
- ✔ Rough idling or engine hesitation
- ✔ Failed emissions test
- ✔ Harsh or erratic automatic transmission shifting
Plug-and-Play Installation: No Dealer Visit Required
Installing your new PCM is a straightforward process you can do at home. Follow these steps for a successful replacement:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the PCM: On the 1999 Alero, the PCM is typically located in the center of the dash, accessible from the passenger side footwell area. You may need to remove a lower dash panel for access.
- Disconnect Connectors: Carefully unclip and remove the electrical wiring harnesses from the old module. Inspect the connectors for any signs of corrosion or damage and clean them with electrical contact cleaner if necessary.
- Remove Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install New Module: Mount your new, pre-programmed PCM onto the bracket and securely reconnect all wiring harnesses. Ensure they click into place.
- Final Step: Reconnect the negative battery terminal. The vehicle may need to go through a brief idle relearn procedure, which typically involves starting the engine and letting it idle for a few minutes.
Guaranteed Compatibility
This module is a direct replacement for units with the following service numbers. Please match one of these numbers to the one on your current PCM to ensure perfect fitment: 09356741, 16236757, 9357034, 9357440, 9366314. It is also compatible with a wide range of 1998-1999 GM vehicles, including the Grand Am, Cutlass, LeSabre, and many more as detailed in our fitment list.