Is Your Trusted GM Truck or Van Suddenly Unreliable?
There’s nothing more frustrating than turning the key on your workhorse truck or family SUV only to be met with a check engine light, rough running, or a complete no-start condition. For many 1998-1999 GM vehicles, the cause isn’t a bad sensor or a mechanical failure—it’s the brain of the operation, the Powertrain Control Module (PCM). When the PCM fails, it can leave you stranded and stressed. This fully programmed PCM is the definitive, straightforward solution to get your vehicle back on the road, running exactly as it should.
Common Symptoms & Your Solution
A failing PCM can cause a host of confusing issues that might seem unrelated. If your truck, van, or SUV is experiencing any of the following, a faulty computer is the likely culprit:
- Check Engine Light: Particularly for internal module error codes like P0601, P0602, P0604, or P0606.
- No-Start or Intermittent Starting: The engine cranks but won’t fire up, or only starts sporadically.
- Poor Engine Performance: Noticeable loss of power, stumbling, hesitation, or rough idling.
- Harsh or Incorrect Shifting: The transmission may shift erratically, late, or not at all.
- Reduced Fuel Economy: A sudden, unexplained drop in MPG can be a sign the PCM isn’t managing the engine correctly.
This replacement module is the solution. It’s not just a part in a box; it’s a complete service. We use your vehicle’s unique VIN to flash the unit with the latest official GM software updates before it ships. This ensures it communicates perfectly with your specific vehicle, restoring its original performance and reliability. By using a quality, tested part like this Programmed 1999 GMC 1500 PCM 16258815, you are choosing a dependable and cost-effective repair.
Features & Real-World Benefits
- ✔ VIN-Programmed for Your Vehicle: Arrives ready for installation. No expensive trips to the dealership for programming are required, saving you time and money.
- ✔ Loaded with Latest GM Updates: We flash the module with the most current software, which can resolve factory bugs and improve overall drivability and efficiency.
- ✔ Restores Peak Performance: A correctly functioning PCM ensures precise fuel delivery, ignition timing, and transmission control, bringing back the smooth, reliable power you depend on.
- ✔ Direct-Fit Replacement: Guaranteed to fit a wide range of GM trucks, vans, and SUVs. Cross-references with part numbers 09355699, 16266645, 9355699, and more.
- ✔ Smart, Economical Repair: Get the functionality and reliability you need without the high cost of a brand-new unit from the dealer.
- ✔ Peace of Mind Included: This unit is backed by our one-year replacement warranty.
Expert Insight: The Heart of Your Vortec Engine
As a technician who’s spent decades working on these GM trucks, I can tell you the PCM from this era is a true workhorse. It’s the central command for the legendary Vortec engine and the robust 4L60E/4L80E transmissions. It’s not just managing the engine; it’s constantly making micro-adjustments to fuel trim, spark advance, and transmission shift points. That’s why simply swapping in a used computer from a junkyard rarely works. Without the correct VIN-specific programming, the vehicle may not start at all due to the anti-theft system (VATS), or it might run poorly because of mismatched calibrations. This Programmed 1999 GMC 1500 PCM 16258815 is prepared correctly, ensuring all systems integrate seamlessly, just like the original.
Frequently Asked Questions
How do I provide my VIN?
After you complete your purchase, you will need to send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship your PCM without it. You can typically find your VIN on your vehicle’s dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Will I need to do anything after I install it?
In most cases, you will need to perform a security relearn procedure to sync the new PCM with your vehicle’s anti-theft system. This is a simple procedure that typically involves turning the key on and off in a specific sequence and does not require special tools. We can provide instructions for this process.
Is this a new part?
No, this is a high-quality, tested computer that has been sourced from a salvaged vehicle. Each unit is inspected and verified to be in excellent working condition before it is programmed and shipped to you.
How can I be sure this fits my vehicle?
This PCM, identified by service numbers 16258815 and 09355699, fits a very wide range of 1998-1999 GM vehicles. Please review the detailed fitment list on this page. The most important step is providing us with your VIN, which allows us to load the exact correct software for your specific make, model, engine, and options.
What’s the difference between a PCM and an ECM?
The terms are often used interchangeably. PCM (Powertrain Control Module) is the more accurate term for these vehicles, as this single module controls both the engine (Engine Control Module – ECM) and the transmission (Transmission Control Module – TCM). This single unit is the brain for your entire powertrain.
Don’t let a bad computer keep you sidelined. Order your Programmed 1999 GMC 1500 PCM 16258815 now and restore the dependability of your vehicle.