Restore Peak Performance to Your GM Truck or SUV
Is your 1998-1999 Chevy Tahoe, GMC Yukon, Suburban, or other GM vehicle running poorly? Experiencing frustrating issues like a persistent check engine light, erratic transmission shifting, a no-start condition, or poor fuel economy? The problem often lies with a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. This fully programmed, service-ready PCM, part number 9355699, is the reliable and effective solution to get your truck back on the road and running like it should.
The Brain of Your Engine: Why the PCM is Critical
The PCM in your late-90s GM vehicle is a sophisticated computer responsible for managing dozens of critical functions. It constantly analyzes data from sensors throughout your engine and transmission to control fuel injection, ignition timing, transmission shift points, emissions systems, and more. When it begins to fail, the symptoms can be widespread and confusing, often mimicking other mechanical problems. Internal component failure, caused by years of heat cycles, vibrations, and electrical stress, can lead to incorrect calculations and commands, throwing your entire powertrain out of sync.
From the Diagnostic Bay
I remember a 1999 Suburban that came into the shop with a complaint of harsh, unpredictable shifting. The owner had already replaced the transmission fluid and filter, and another shop had quoted him for a full transmission rebuild. He was frustrated and ready to give up on the truck. We hooked up our diagnostic scanner and noticed that while the transmission codes were present, the data from the PCM looked erratic. The voltage readings were inconsistent. On a hunch, we swapped in a known-good, programmed PCM. The truck immediately started shifting perfectly. The original PCM had a failing driver that controlled the transmission solenoids, a common issue on these units. It saved the customer thousands of dollars and reinforced a key lesson: always suspect the computer when multiple, seemingly unrelated electronic symptoms appear.
Your Plug-and-Play Solution: VIN-Programmed for Your Vehicle
Finding a replacement PCM isn’t enough. For your vehicle to function correctly, the module must be programmed with the specific software for your vehicle’s Vehicle Identification Number (VIN). This ensures it has the correct parameters for your engine size, transmission type, emissions equipment, and other factory options. Our service eliminates the guesswork and the need for an expensive trip to the dealership. When you order, simply provide us with your VIN. We will flash this module with the latest, most stable GM-certified software for your exact vehicle. This means when it arrives, it’s ready for installation, making the repair process as simple as possible.
Symptoms of a Failing 1998-1999 Tahoe PCM
A failing PCM can cause a wide range of issues. If your vehicle is experiencing one or more of the following symptoms, a faulty control module could be the culprit. This unit is the correct replacement for these problems.
- ✔ Check Engine Light: The light is on, and you may have codes related to sensors, emissions, or internal module failure (e.g., P0601, P0605).
- ✔ No-Start or Hard-Start: The engine cranks but won’t start, or starts only after extended cranking, due to incorrect fuel or spark control.
- ✔ Poor Engine Performance: Noticeable loss of power, hesitation, stumbling, or misfiring.
- ✔ Erratic Shifting: The transmission may shift harshly, slip between gears, or get stuck in one gear (limp mode).
- ✔ Reduced Fuel Economy: A sudden and unexplained drop in your vehicle’s MPG.
- ✔ Failed Emissions Test: Inability to pass a smog check due to monitor readiness issues or active trouble codes.
- ✔ Intermittent Stalling: The engine may stall for no apparent reason while driving or at an idle.
Guaranteed Compatibility
This PCM, identified by service number 09355699, is a direct replacement for a wide array of 1998 and 1999 General Motors trucks, vans, and SUVs. It is compatible with several original part numbers, including 16266645, 16250279, 16258815, and 09366810. Please verify the part number on your original module and consult our detailed fitment list to ensure this is the correct component for your vehicle. Our VIN programming process further guarantees that the software will be a perfect match for your specific application.
Frequently Asked Questions
Do I need to do anything after installing this PCM?
In most cases, you will need to perform a security relearn procedure, also known as a CASE (Crankshaft Angle Sensor Error) relearn. This can often be done without special tools and involves a sequence of key turns. Instructions are readily available online for your specific model, or your mechanic can perform it in minutes.
Is this a new part?
No, this is a high-quality, genuine GM part sourced from a salvaged vehicle. Each unit is thoroughly inspected and tested before being programmed with your vehicle’s specific software. This provides OEM reliability at a fraction of the cost of a new module.
How do I provide my VIN?
After you complete your purchase, you can send us your 17-digit VIN through the messaging system. We cannot program and ship your module without this information, so please provide it promptly to avoid delays.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM directly controls the electronic solenoids in the transmission. If the PCM’s internal drivers for these solenoids are failing, it will cause harsh or erratic shifting. If your vehicle has been mechanically inspected and the transmission is healthy, a faulty PCM is a very likely cause.
What is the difference between a PCM, ECM, and ECU?
The terms are often used interchangeably. ECM (Engine Control Module) typically just controls the engine. PCM (Powertrain Control Module) controls both the engine and the transmission. ECU (Electronic Control Unit) is a more generic term. For these GM trucks, PCM is the most accurate term as this single module manages the entire powertrain.