Is Your GM Vehicle Running Rough? The PCM Might Be the Culprit.
If your late-90s or early-2000s GM vehicle, such as a 1999 Chevrolet Lumina, is experiencing baffling engine problems, you’re not alone. Issues like stalling, erratic shifting, a persistent Check Engine Light, or even a complete no-start condition can often be traced back to a single, critical component: the Powertrain Control Module (PCM). This computer is the brain of your vehicle’s engine and transmission, and when it fails, it can cause a wide range of frustrating and difficult-to-diagnose symptoms. This listing is for a dependable, tested, used GM PCM with part number 09361735, programmed specifically for your car to restore its original performance and reliability.
From the Diagnostic Bay
I remember a 1999 Pontiac Grand Prix GTP that came in on a tow truck. The owner was at his wit’s end. The car would run fine for 20 minutes, then suddenly die and refuse to restart for an hour. He’d replaced the crank sensor, the fuel pump, and the ignition control module. No codes were stored. We hooked up our scanner and monitored live data. Everything looked perfect… until it didn’t. Just before it stalled, we saw the injector pulse width go haywire. We suspected the PCM was failing under heat. We swapped in a known-good, programmed module just like this one, let the car run for over an hour, and the problem was gone. It’s a classic case where a failing computer mimics other component failures, making a direct replacement 1999 Lumina PCM the only real solution.
Common Symptoms of a Failing PCM
- ✔ Check Engine Light: The light may be on constantly, or it may flash intermittently. You might see codes related to multiple, unrelated sensors.
- ✔ No-Start or Hard-Start: The engine cranks but refuses to fire up, or takes an excessively long time to start, especially when warm.
- ✔ Poor Engine Performance: You may experience rough idling, stalling, hesitation during acceleration, or a noticeable loss of power.
- ✔ Decreased Fuel Economy: A faulty PCM can’t properly manage the air-fuel mixture, leading to your vehicle consuming more gasoline than usual.
- ✔ Erratic Transmission Shifting: The PCM also controls automatic transmission functions. You might notice harsh shifts, delayed engagement, or the transmission getting stuck in one gear (limp mode).
- ✔ Failed Emissions Test: An inability to communicate with the OBD-II port or incorrect sensor readings will cause an automatic failure.
The Right Solution: A VIN-Programmed Module
Simply swapping a used computer from another vehicle won’t work. Modern vehicles use sophisticated anti-theft systems and have specific software calibrations for different engines, transmissions, and vehicle options. That’s why our process is designed for success. When you purchase this module, you provide us with your vehicle’s 17-digit Vehicle Identification Number (VIN). Our technicians then use official GM equipment to flash the unit with the latest, most up-to-date software specific to your car. This ensures that the engine parameters, transmission shift points, and security information are a perfect match, making installation as straightforward as possible.
Wide-Ranging Compatibility for Your GM Vehicle
This PCM, part number 9361735, was a workhorse for General Motors, serving as the central controller for a huge variety of popular sedans, minivans, and coupes. While this is the correct 1999 Lumina PCM, it also fits many other models. Please verify your original part number and consult the list below to ensure compatibility. This module is the correct fit for the following vehicles:
- EIGHTY EIGHT 99 Electronic Control Module; (LH engine compartment)
- GRAND PRIX 99-00 Electronic Control Module; (LH engine compartment)
- BONNEVILLE 99-00 Electronic Control Module; (LH engine compartment)
- CUTLASS 99 Electronic Control Module; (LH center dash), ID 9361735
- INTRIGUE 99 Electronic Control Module; (LH engine compartment)
- RIVIERA 99 Electronic Control Module; (RH dash)
- SILHOUETTE 99 Electronic Control Module; (LH engine compartment)
- VENTURE 99 Electronic Control Module; (LH engine compartment)
- IMPALA 00 Electronic Control Module; (LH engine compartment), 3.4L or 3.8L
- MONTANA 99 Electronic Control Module; (LH engine compartment)
- CENTURY 99 Electronic Control Module; (LH engine compartment)
- PARK AVENUE 99 Electronic Control Module; (LH front engine compartment)
- TRANS SPORT 99 Electronic Control Module; (Canada, LH front engine compartment)
- LUMINA CAR 99 Electronic Control Module; (LH engine compartment)
- REGAL 99 Electronic Control Module; (LH engine compartment)
- MALIBU 99 Electronic Control Module; (LH dash), 3.1L
- LESABRE 99-00 Electronic Control Module; (LH front engine compartment)
- MONTE CARLO 99-00 Electronic Control Module; (LH engine compartment)
Installation and Security Relearn
After receiving your pre-programmed PCM, installation is typically straightforward. Disconnect the vehicle’s battery, locate and remove the old module, and install the new one. After reconnecting the battery, you will likely need to perform a security relearn procedure. This allows your vehicle’s anti-theft system (like GM’s Passlock or Passkey) to recognize the new computer. A common procedure is the “30-minute relearn”:
- Turn the key to the “ON” position (do not start the engine).
- Attempt to start the engine, then release the key back to the “ON” position. The “Security” light on the dash should be flashing.
- Leave the key in the “ON” position for approximately 10-11 minutes, until the “Security” light stops flashing and turns off.
- Turn the key to the “OFF” position for 10 seconds.
- Repeat steps 1-4 two more times for a total of three 10-minute cycles.
- After the third cycle, the vehicle should start and run with the new PCM.
Note: This is a general guide. Please consult a service manual for the exact procedure for your specific vehicle.
Frequently Asked Questions
Do I need to do anything after installing this PCM?
Yes. While the module comes programmed to your VIN, nearly all GM vehicles of this era require a security relearn procedure to sync the new PCM with your car’s anti-theft system. We have provided a general guide above, but you should consult a repair manual for your specific model.
Where can I find my VIN?
Your 17-digit Vehicle Identification Number (VIN) can be found on a metal plate on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, and on your vehicle’s registration and insurance documents.
Is this a new part?
No, this is a high-quality, tested, and fully functional used part that has been sourced from a salvaged vehicle. Each unit is inspected and verified to be in excellent working condition before being programmed and shipped.
Why does the PCM need my VIN?
The VIN is the key to your vehicle’s identity. It tells us the exact engine, transmission, emissions equipment, and other options your car was built with. Programming the PCM with your VIN ensures it has the correct software and calibrations to operate your vehicle exactly as the factory intended.
What if my original part number is different?
GM often uses several part numbers for the same component. While 9361735 is a very common part number for these applications, it’s always best to match it to your original. If you are unsure, please contact us with your VIN and original part number before ordering.
Will this fix my car’s problem for certain?
This module will resolve any issue directly caused by a faulty PCM. However, it’s crucial that the vehicle is diagnosed correctly. This part will not fix problems caused by bad sensors, wiring issues, or mechanical failures. We recommend a thorough diagnosis by a qualified technician.