Restore Your GM’s Performance and Reliability
If you’re dealing with a frustrating Check Engine Light, erratic engine behavior, or a no-start condition in your 1998-1999 Pontiac Grand Am, the Powertrain Control Module (PCM) is often the culprit. As the central computer for your engine and transmission, a failing PCM can cause a cascade of problems that are difficult to diagnose. I’ve spent two decades in the garage, and I’ve seen firsthand how a faulty module can mimic other issues, leading to wasted time and money on unnecessary parts.
This isn’t just a replacement part; it’s a complete solution. We take the guesswork and hassle out of the repair by programming this module specifically for your vehicle using your VIN. This ensures all the latest GM software updates are loaded, which can resolve factory bugs and improve drivability and fuel efficiency. You get a component that’s ready for installation right out of the box, saving you a costly trip to the dealership for programming.
Case Study: A Tricky Diagnosis
A customer brought in a ’99 Oldsmobile Alero with the 3.4L V6—a vehicle that shares this exact PCM with the Grand Am. The car had an intermittent no-start condition that left two other shops stumped. It would run fine for days, then refuse to start, with no consistent error codes. After checking all the usual suspects (crank sensor, fuel pump, ignition system), I focused on the PCM. By monitoring live data during a failure, I saw the 5-volt reference signal dropping out intermittently. This is a classic sign of an internal PCM short. We installed a VIN-programmed module, performed the security relearn, and the car has run flawlessly ever since. It’s a reminder that when electronics act up without a clear pattern, the computer itself is often the root cause.
Is Your Vehicle Showing These Symptoms?
A failing PCM can manifest in various ways. If you’re experiencing any of the following, this module is the likely solution for your 1998-1999 Grand Am PCM issues.
- ✔ Persistent Check Engine Light (CEL)
- ✔ Stored diagnostic trouble codes (DTCs) like P0601, P0602, or P0606
- ✔ Engine stalling, stumbling, or misfiring
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Complete no-start or intermittent starting problems
- ✔ Poor fuel economy
- ✔ Failure to pass an emissions test
A Straightforward Guide to PCM Installation
Replacing the PCM on these GM vehicles is a manageable job for a DIYer with basic tools. Follow these steps carefully for a successful installation.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On the 1999 Grand Am and Alero, the PCM is typically located in the center of the dashboard, accessible from the passenger side footwell or by removing the glove box. On other models like the Venture or Silhouette, it may be in the engine compartment. Consult a repair manual for your specific vehicle’s location.
- Disconnect Connectors: Carefully unclip the wiring harness connectors from the old PCM. These connectors have locking tabs that need to be released. Do not force them.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM into the bracket and securely reconnect the wiring harnesses. Ensure they click into place.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: This is a critical step. Turn the key to the ‘ON’ position (don’t start the engine) for 10-15 minutes, or until the ‘Security’ light on the dash stops flashing and turns off. Turn the key off for 10 seconds, then the vehicle should start. This procedure pairs the new PCM with your vehicle’s anti-theft system.
Verified Vehicle Compatibility
This module is a direct replacement for service numbers 09356741, 16236757, 9356741, 9357034, 9357440, and 9366314. It is guaranteed to fit the following GM models:
- 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 (3.1L)
- Grand Am 1999 (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)
Frequently Asked Questions about your 1998-1999 Grand Am PCM
Frequently Asked Questions
How do I provide my VIN for programming?
After you complete your purchase, you will receive instructions on how to send us your vehicle’s 17-digit VIN. We cannot ship the module until we receive this information, as the programming is essential for it to function in your car.
Is this part difficult to install myself?
For someone with basic mechanical skills, the physical installation is straightforward. The most important part is performing the security relearn procedure correctly after installation. Our guide above outlines this process.
Will this fix my failed emissions test?
If the failure was caused by a PCM-related error code or poor engine management (like incorrect air/fuel ratio), then yes, this module is very likely to resolve the issue and allow your vehicle to pass.
What is the difference between a PCM and an ECM?
The terms are often used interchangeably. ECM (Engine Control Module) typically just controls engine functions. A PCM (Powertrain Control Module) is more integrated and controls both the engine and the automatic transmission, which is standard on these GM vehicles.
Does this module come with a warranty?
Yes, all of our modules come with a comprehensive warranty. Please see the warranty details section on this page for specific terms and duration.