Restore Peak Performance to Your GM Vehicle
Is your 1998 Buick Riviera or other GM vehicle suffering from frustrating, hard-to-diagnose issues? A failing Powertrain Control Module (PCM), the computer brain of your car, is often the culprit behind problems like a persistent check engine light, poor fuel economy, erratic shifting, or even a no-start condition. Over my 20 years in the shop, I’ve seen how a faulty PCM can mimic a dozen other problems, leading owners down a rabbit hole of expensive and unnecessary repairs. This module is the definitive solution, designed to restore your vehicle’s original performance and reliability.
This isn’t just a replacement part; it’s a complete, ready-to-install solution. We take your vehicle’s unique Vehicle Identification Number (VIN) and flash this PCM with the very latest GM-certified software. This critical step ensures that all fuel trim, transmission shift points, and engine parameters are perfectly calibrated for your specific car. By ordering from us, you bypass the expensive trip to the dealership for programming—a service that can often cost hundreds of dollars on its own. This is the smart, efficient way to get your car back on the road.
From the Diagnostic Bay: The Case of the Intermittent Stall
A customer brought in a ’98 Pontiac Bonneville with the 3.8L V6, a car that shares this exact PCM. The complaint was maddening: it would run perfectly for days, then suddenly stall at a stoplight and refuse to restart for 10-15 minutes. No consistent codes were stored, just a history of random communication errors. We checked fuel pressure, ignition components, and wiring harnesses—all were fine. Experience pointed to the PCM. Heat soak was causing an internal circuit to fail intermittently. We installed one of our VIN-programmed modules, and the problem was solved instantly. The customer saved time and the cost of chasing phantom issues, proving that sometimes the most direct fix for a complex electronic problem is replacing the core component.
Is Your GM Showing These Signs of PCM Failure?
A failing engine computer can cause a wide range of symptoms. If you’re experiencing any of the following, a faulty PCM could be the root cause:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Stored diagnostic trouble codes (DTCs) like P0601, P0602, or P0606
- ✔ Vehicle will not start or is difficult to start
- ✔ Engine stalling or cutting out unexpectedly
- ✔ Rough or unpredictable automatic transmission shifting
- ✔ Noticeable drop in fuel mileage
- ✔ Failure to pass state emissions testing
A Straightforward Guide to Installation
Installing your new 1998 Riviera Powertrain Control Module is a job most DIYers can handle with basic tools. Our pre-programming service makes it a true plug-and-play repair.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most of these GM vehicles, the PCM is located in the engine bay, often inside the air filter box housing for protection. Consult a repair manual for your specific model if you’re unsure.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that need to be released. Once disconnected, unbolt the old module and remove it from the vehicle.
- Install the New Module: Seat the new, pre-programmed PCM in the mounting location and secure it with the original bolts. Reconnect the electrical harnesses, ensuring they click securely into place.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: Most GM vehicles of this era require a simple key-cycle security relearn procedure to sync the new PCM with your vehicle’s anti-theft system. Typically, this involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times. Your vehicle should then start and run correctly.
Verified Vehicle Compatibility
This module is a direct-fit replacement for a wide range of GM vehicles. Please verify your model and engine below. This part is compatible with service numbers 09356741, 16236757, 9357034, 9357440, and 9366314.
- ACHIEVA 98 (3.1L)
- ALERO 99 (3.4L)
- BONNEVILLE 98
- CAMARO 98 (3.8L)
- CENTURY 98 (3.1L)
- CUTLASS 98-99
- EIGHTY EIGHT 98
- FIREBIRD 98 (3.8L)
- GRAND AM 98 (3.1L)
- GRAND AM 99 (3.4L)
- GRAND PRIX 98
- INTRIGUE 98
- LESABRE 98 (3.8L)
- LUMINA CAR 98
- MALIBU 98 (3.1L)
- MONTE CARLO 98
- PARK AVENUE 98 (3.8L)
- REGAL 98
- RIVIERA 98 (3.8L)
- SILHOUETTE 98
- SKYLARK 98 (3.1L)
- TRANS SPORT 98
- VENTURE 98 (3.4L)
Frequently Asked Questions About This 1998 Riviera Powertrain Control Module
Do I need to do anything after I buy it?
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST send us your vehicle’s 17-digit VIN. We cannot program and ship your module without it. This ensures the PCM is a perfect match for your car’s factory settings.
Is this part difficult to install?
Not at all for most DIYers. Since we program it beforehand, it’s a plug-and-play installation. You’ll just need basic hand tools to swap the module and perform a simple security relearn procedure, which requires no special equipment.
Will this fix my check engine light?
If the check engine light is caused by an internal PCM failure (like codes P0601-P0606), then yes, this part is the correct fix. However, you should always diagnose the stored codes properly to ensure the issue isn’t a faulty sensor or wiring.
What is a security relearn?
It’s a simple procedure that syncs the new PCM to your car’s anti-theft system. Without it, the car may not start. It typically involves cycling the ignition key and waiting for about 10-15 minutes. Instructions are readily available online for your specific model.
Is this a brand new part?
This is a high-quality, inspected, and tested replacement part that is guaranteed to function to OE specifications. We load it with the newest available software from GM to ensure optimal performance and longevity.