Restore Your Truck’s Reliability and Performance
Is your trusty GMC 1500 suddenly giving you headaches? If you’re dealing with frustrating issues like a no-start condition, rough idling, poor fuel mileage, or a persistent Check Engine Light, the problem often points directly to a failing Powertrain Control Module (PCM). As the electronic brain of your truck, the PCM governs everything from fuel delivery and spark timing to transmission shifting. When it falters, your whole vehicle suffers. This isn’t just an inconvenience; it can leave you stranded. This replacement PCM is your direct, reliable solution to get your truck back to its dependable self.
A Technician’s Notebook: The Intermittent Stall Mystery
I remember a ’99 Chevy Silverado—a nearly identical platform to your GMC—that came into my bay with an intermittent stalling problem that was driving the owner crazy. He’d already replaced the fuel pump and filter, thinking it was a fuel delivery issue. The truck would run fine for days, then die at a stoplight without warning. No codes were stored initially. After hooking up my diagnostic scanner and monitoring live data, I noticed the PCM would occasionally stop communicating for a split second right before the engine cut out. This is a classic sign of an internal PCM failure. We swapped in a quality, correctly programmed PCM like this one, and the problem was solved instantly. It saved the owner from throwing more parts at a problem that wasn’t there—a testament to diagnosing the core issue first.
Is Your Truck Showing These Symptoms?
A failing PCM can manifest in several ways. If you’re experiencing any of the following, it’s a strong indicator that your engine computer needs replacement. In my 20+ years of experience, these are the most common signs I’ve seen in the shop for these specific GM trucks.
- ✔ Check Engine Light is on with codes like P0601, P0602, or P0605 (Internal Control Module Memory/Programming Errors).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling or rough, erratic idling.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ The scanner cannot communicate with the PCM (U-codes).
The Smart, Hassle-Free Solution for Your 1998-1999 GMC 1500 PCM
Don’t let a faulty computer keep your truck off the road. This isn’t just a used part pulled from a yard; it’s a fully vetted and prepared solution. We take a genuine, OEM-quality PCM and flash it with the latest official GM software updates specifically for your vehicle. By providing your Vehicle Identification Number (VIN) at checkout, you receive a module that is truly plug-and-play. This process ensures all factory parameters for your engine, transmission, and emissions systems are perfectly matched, restoring original performance and efficiency. You get the reliability of correct software without the dealership price tag or the need for expensive programming tools.
A Straightforward Guide to Installation
You don’t need to be a master mechanic to install this PCM. With basic hand tools, you can get this job done in your own driveway. Follow these simple steps:
- Safety First: Always disconnect the negative terminal from your truck’s battery before working on any electronic components.
- Locate the PCM: On your 1998-1999 GMC 1500, the PCM is typically located in the engine compartment on the driver’s side, near the fender or firewall.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old PCM. They have locking tabs that need to be released. Once disconnected, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, programmed PCM into the mounting bracket. Firmly reconnect the electrical connectors, ensuring they click securely into place.
- Reconnect Power: Reattach the negative battery terminal and tighten it securely.
- Final Step: Start the engine. In some cases, a CASE (Crankshaft Angle Sensor Error) Relearn procedure may be required to clear a code and optimize timing. This can be done with many professional-grade scan tools.
Verified Vehicle Compatibility
This module is a direct replacement for service number 9366810 and is interchangeable with part numbers 09355699, 16266645, 16250279, and 16258815. It is confirmed to fit the following vehicles. Please match your part number or vehicle to ensure correct fitment.
• 1500/2500/3500 Pickup (1998-1999, Gas)
• Suburban 1500/2500 (1998-1999, Gas)
• Tahoe (1998-1999, Gas)
• Astro / Blazer S10 (1998)
• S10 Pickup (1998, 4.3L)
• Express 1500/2500/3500 Van (1998-1999, Gas)
GMC:
• 1500/2500/3500 Pickup (1998-1999, Gas)
• Yukon / Suburban (1998-1999, Gas)
• Safari / Jimmy S15 (1998)
• Sonoma (1998, 4.3L)
• Savana 1500/2500/3500 Van (1998-1999, Gas)
Other GM:
• Cadillac Escalade (1999)
• Oldsmobile Bravada (1998)
• Isuzu Hombre (1998, 4.3L)
Frequently Asked Questions
How do I provide my VIN for programming?
After you complete your purchase, you will receive instructions on how to send us your vehicle’s 17-digit VIN. We cannot ship your order until we receive this information, as it is essential for programming the module correctly for your specific truck.
Is this part difficult to install myself?
No, installation is straightforward for someone with basic mechanical skills. It involves disconnecting the battery, unplugging the old module, and plugging in the new one. No special programming tools are needed on your end since we handle all the flashing before it ships.
What is a CASE Relearn and will I need to do one?
A CASE (Crankshaft Angle Sensor Error) Relearn synchronizes the PCM with the crankshaft position sensor. After installing the new PCM, you might get a P1336 code. While the truck will run, performing a CASE relearn with a compatible scan tool will clear this code and ensure optimal engine timing and performance. Many local repair shops can perform this service quickly if you don’t have the tool.
Is this a new part?
This is a high-quality, tested used OEM part sourced from a salvaged vehicle. We inspect each unit for integrity and then program it with the latest GM software to ensure it functions reliably, offering a cost-effective alternative to a brand-new module.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls the electronic solenoids in the transmission. If your shifting issues are caused by faulty signals from the computer, replacing it with this correctly programmed unit should resolve the problem. However, it will not fix internal mechanical failures within the transmission itself.