Is Your Late 90s GM Truck or Van Acting Up?
If you’re dealing with frustrating issues like a persistent check engine light, rough idling, stalling, or erratic transmission shifting in your 1998-1999 GM vehicle, a failing Powertrain Control Module (PCM) is a very likely culprit. This module is the electronic brain of your engine and transmission, and when it starts to fail, it can cause a host of problems that are often misdiagnosed. Don’t waste time and money replacing sensors and other components. Get the direct-fit, correctly programmed solution with this genuine OEM PCM.
From the Diagnostic Bay
I once had a 1999 Suburban come into the shop that had its owner at his wit’s end. He’d replaced the throttle position sensor, the mass air flow sensor, and even the fuel pump based on various recommendations. The truck still ran rough, hesitated on acceleration, and would occasionally stall at red lights. After hooking up the scanner, I saw erratic data streams that didn’t point to any single sensor. Experience told me to check the source – the PCM. We swapped in a pre-programmed unit just like this one, performed the security relearn, and the truck immediately ran like it just rolled off the factory floor. The owner couldn’t believe the fix was that straightforward after months of chasing ghosts.
Common Symptoms of a Failing PCM
- ✔ Check Engine Light is on with various, often inconsistent, trouble codes.
- ✔ Engine cranks but refuses to start.
- ✔ Poor fuel economy and noticeable loss of power.
- ✔ Rough or unpredictable engine idling.
- ✔ Harsh or delayed transmission shifting.
- ✔ Stalling for no apparent reason, either while driving or at a stop.
- ✔ Failure to pass an emissions test.
The Right Solution for Your 1998-1999 Express PCM
This isn’t just a used part pulled from a vehicle. This is a complete, ready-to-install solution. We take a tested, genuine OEM computer and professionally program it with the latest official GM software updates specifically for your vehicle. All we need is your Vehicle Identification Number (VIN) at checkout. This process ensures that the module communicates perfectly with your truck’s engine, transmission, and all related systems, restoring its original performance and reliability. By having it pre-programmed, you skip the expensive trip to a dealership and the high cost of their programming services.
Simple Installation Process
Installation is straightforward. Simply disconnect the battery, locate and unplug your old PCM, and install this replacement unit. Once installed and the battery is reconnected, you may need to perform a simple security relearn procedure (often called a Passlock or VATS relearn), which can typically be done in your driveway with just the ignition key. This ensures the vehicle’s anti-theft system recognizes the new computer. This step is critical for the vehicle to start and run.
Guaranteed Compatibility
This PCM, identified by part number 9366810, is a direct replacement for several other service numbers, including 09355699, 16266645, 16250279, and 16258815. It fits a massive range of 1998-1999 GM trucks and vans. Please verify your vehicle is on the list below to ensure proper fitment. If you are unsure, please contact us with your VIN before ordering.
Frequently Asked Questions
Do I need to get this computer programmed?
No. The main benefit of our service is that we program the module for you before we ship it. Simply provide us with your vehicle’s 17-digit VIN when you place your order, and it will arrive ready to be installed.
Where can I find my VIN?
Your 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, or on your vehicle’s registration and insurance documents.
Is this a brand new part?
This is a high-quality, used OEM part sourced from a salvaged vehicle. Each unit is thoroughly inspected and tested to ensure it is fully functional before being programmed and shipped.
What is a security relearn procedure?
It is a simple procedure that syncs the replacement PCM with your vehicle’s anti-theft system. It usually involves turning the ignition key to the ‘ON’ position for about 10-15 minutes, then ‘OFF’, and repeating the cycle two more times. Instructions for this are widely available online for your specific model.
Will this fix my vehicle’s problem?
If your vehicle’s issues are caused by a faulty PCM, this part is the correct solution. While it solves a very common set of problems, we always recommend having a qualified mechanic diagnose your vehicle to confirm the PCM is the point of failure before ordering.