Restore Your Vehicle’s Performance with a Reliable Engine Computer
If you’re dealing with frustrating engine problems in your 1999-2000 Pontiac Grand Prix or another compatible GM vehicle, a failing Powertrain Control Module (PCM) is often the culprit. As a technician with over two decades of experience, I’ve seen firsthand how a faulty engine computer can cause a cascade of issues, from a persistent Check Engine Light to a car that refuses to start. This isn’t just an inconvenience; it’s a reliability issue that can leave you stranded. This listing is for a dependable, used OEM PCM, part number 09361735, that serves as the ‘brain’ of your vehicle’s engine and transmission.
What makes this a smart solution is that we take the guesswork and extra cost out of the repair. Before this module ever leaves our facility, we program it specifically to your car using the Vehicle Identification Number (VIN) you provide. This process includes loading the latest software updates from General Motors, ensuring optimal performance and communication between all your vehicle’s systems. This pre-programming service saves you a costly trip to the dealership and the hassle of finding a shop with the right equipment to flash a blank module. It’s a direct, effective fix designed to get you back on the road with confidence.
Real-World Repair Story
Real-World Repair Story
I remember a 2000 Pontiac Bonneville that came into my bay with a ghost of a problem. The owner complained of random stalling at traffic lights and an occasional no-start condition that would magically fix itself. We checked fuel pressure, spark, and sensors—everything tested fine. No consistent trouble codes were stored, just a few random communication errors. After days of chasing wires, we decided to test the PCM. On a hunch, we tapped the module with a screwdriver handle while the engine was running, and it immediately stalled. The culprit was an internal failure in the original 1999-2000 Grand Prix PCM, a common issue on these older GM platforms. A replacement, programmed module like this one had the car running perfectly in under an hour.
Is Your GM Vehicle Showing These PCM Failure Signs?
A failing engine computer can manifest in numerous ways. If you’re experiencing any of the following, it might be time to inspect your PCM. Look out for:
- ✔ Persistent Check Engine Light with codes such as P0601 (Internal Control Module Memory Check Sum Error), P0605 (Read Only Memory Error), or other communication-related faults.
- ✔ Unexplained stalling or engine cutting out while driving.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A no-start condition where the engine cranks but won’t fire up.
- ✔ Noticeable decrease in fuel economy.
- ✔ Misfires or a rough idle that can’t be traced to spark plugs, coils, or injectors.
- ✔ Intermittent failure of gauges on the instrument cluster.
Your Straightforward Installation Roadmap
Installing your programmed 1999-2000 Grand Prix PCM is a manageable job for a DIY enthusiast. While the exact location varies slightly by model, the process is generally the same. Always consult a service manual for your specific vehicle.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental reconnection.
- Locate the PCM: On most compatible models like the Grand Prix, Impala, and Century, the PCM is located in the air filter box housing in the left-hand (driver’s side) engine compartment. For others like the Riviera, it may be under the dash. Verify its location before you begin.
- Disconnect the Harnesses: Carefully release the locking tabs and unplug the wiring harnesses from the old PCM. Inspect the connectors for any corrosion or bent pins.
- Remove the Old Module: Unbolt or unclip the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Seat your replacement PCM into the mounting bracket and secure it. Reconnect the wiring harnesses, ensuring they click securely into place.
- Reconnect the Battery: Reattach the negative battery terminal.
- Perform Security Relearn Procedure: After installation, you MUST perform a VATS/Passlock security relearn. This simple procedure typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows your vehicle to recognize the new PCM. Your car will not start until this is completed.
Verified Compatibility for Your Vehicle
This module, part number 09361735, is a direct-fit replacement for a wide range of GM cars and vans. Please verify your part number and check the list below to ensure proper fitment. Note the specific engine or option requirements.
Chevrolet: Impala (00 – 3.4L & 3.8L), Lumina Car (99), Malibu (99 – 3.1L), Monte Carlo (99-00), Venture (99)
Oldsmobile: Cutlass (99), Eighty Eight (99), Intrigue (99), Silhouette (99)
Pontiac: Bonneville (99-00 – 3.8L), Grand Prix (99-00 – 3.8L, incl. supercharged), Montana (99), Trans Sport (99 – Canada)
Do I need to do anything after I purchase?
Real-World Repair Story
I remember a 2000 Pontiac Bonneville that came into my bay with a ghost of a problem. The owner complained of random stalling at traffic lights and an occasional no-start condition that would magically fix itself. We checked fuel pressure, spark, and sensors—everything tested fine. No consistent trouble codes were stored, just a few random communication errors. After days of chasing wires, we decided to test the PCM. On a hunch, we tapped the module with a screwdriver handle while the engine was running, and it immediately stalled. The culprit was an internal failure in the original 1999-2000 Grand Prix PCM, a common issue on these older GM platforms. A replacement, programmed module like this one had the car running perfectly in under an hour.