Restore Peak Performance to Your GM Truck or SUV
Is your trusty 1998 GMC Envoy or another classic GM vehicle suddenly giving you headaches? If you’re dealing with a persistent Check Engine Light, erratic engine behavior, or a no-start condition that has you stumped, the culprit is often the Powertrain Control Module (PCM), the central computer of your vehicle. Over time, these modules can fail due to heat, vibration, and age. This replacement Powertrain Control Module is the reliable, straightforward solution to get your vehicle running smoothly again.
Unlike sourcing a part from a junkyard with an unknown history, this module comes programmed specifically for your vehicle. We use your Vehicle Identification Number (VIN) to flash the unit with the latest official GM software updates. This critical step ensures proper communication between your engine and transmission, restoring factory performance, fuel efficiency, and emissions control. Stop chasing ghosts in the machine and install a part you can depend on.
A Technician’s Notebook
I remember a 1999 Chevy Suburban that came into the bay with a complaint of intermittent stalling at stoplights. The owner had already replaced the fuel filter and was convinced it needed a fuel pump. I scanned it and found no hard codes, just a history of random communication faults. Instead of just throwing a pump at it, I monitored the live data from the PCM. I noticed the 5-volt reference signal would occasionally drop out for a split second—just before the engine would stumble. That’s a classic sign of an internal PCM failure. We installed a VIN-programmed module just like this one, and the problem was solved. The customer saved hundreds by avoiding a fuel pump replacement he didn’t need.
Common Signs of a Failing PCM
- ✔ Check Engine Light is on with codes like P0601, P0605, or P0606.
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Intermittent stalling or rough idling.
- ✔ Failure to pass an emissions test.
- ✔ Communication errors with your scan tool.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- ✔ Locate the Module: On most of these vehicles, the PCM is located in the engine bay. On S10/Blazer platforms, it’s typically on the passenger side firewall or inner fender. On full-size trucks and vans, it’s often on the driver’s side inner fender, near the battery.
- ✔ Disconnect Connectors: Carefully unclip the wiring harness connectors from the old PCM. These connectors have locking tabs that may need to be gently pried up.
- ✔ Remove the Old PCM: Unbolt the module from its mounting bracket. Keep the hardware as you will need it for the new unit.
- ✔ Install the New PCM: Mount the new module securely onto the bracket and re-install the hardware.
- ✔ Reconnect Everything: Plug the wiring harnesses firmly into the new PCM until they click. Reconnect the negative battery terminal.
- ✔ Perform Security Relearn (If Necessary): In many cases, you may need to perform a simple security relearn procedure, which typically involves turning the key to the ‘ON’ position for 10-15 minutes. This allows the new PCM to recognize your vehicle’s anti-theft system. Consult your vehicle’s service information for the exact procedure.
Guaranteed Fitment for Your GM Vehicle
This module is a direct replacement for part numbers 16250279, 09366810, and 09355699. Please verify your original part number or use the compatibility list below. This part fits the following vehicles:
- Cadillac Escalade: 1999
- Chevrolet Astro Van: 1998-1999
- Chevrolet Blazer S10: 1998
- Chevrolet Express Van (1500, 2500, 3500): 1998
- Chevrolet Pickup (1500, 2500, 3500): 1998-1999
- Chevrolet S10 / Sonoma: 1998
- Chevrolet Suburban (1500, 2500): 1998-1999
- Chevrolet Tahoe: 1998-1999
- GMC Envoy: 1998
- GMC Jimmy S15: 1998
- GMC Pickup (1500, 2500, 3500): 1998-1999
- GMC Safari Van: 1998-1999
- GMC Savana Van (1500, 2500, 3500): 1998
- GMC Yukon: 1998-1999
- Isuzu Hombre: 1998 (4.3L V6)
- Oldsmobile Bravada: 1998
Frequently Asked Questions
Does this PCM require any additional programming?
No. We program the module to your vehicle’s specific VIN before shipping. It arrives ready for installation and, in most cases, a simple security relearn procedure.
Where do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit VIN. We cannot ship the module until we receive this information to ensure correct programming.
What’s the benefit of the latest GM updates?
Over the life of a vehicle, manufacturers often release software updates to fix bugs, improve transmission shift points, and enhance engine efficiency. Our programming ensures your replacement module has these improvements built-in.
Is this a used part?
This is a high-quality, inspected, and tested replacement part, guaranteed to function correctly. Each unit is programmed and verified before shipment.
Will this fix my vehicle’s problem for sure?
This module is a direct solution for a failed PCM. While it resolves the many symptoms listed, it’s always best to have a proper diagnosis performed to rule out other issues like bad sensors or wiring problems.