Is Your 1998-1999 GM Truck or Van Running Rough?
If you’re dealing with frustrating issues like a persistent check engine light, poor fuel economy, erratic shifting, or even a no-start condition, a failing Powertrain Control Module (PCM) could be the culprit. The PCM is the brain of your vehicle, controlling everything from the engine’s fuel mixture and ignition timing to the transmission’s shift points. When it starts to fail, it can cause a cascade of problems that are often difficult to diagnose. Don’t let a faulty computer keep your reliable GM truck off the road. This is a direct-fit, VIN-programmed replacement solution designed to restore your vehicle’s performance and reliability.
The Smart Solution: A VIN-Programmed PCM
Replacing a PCM isn’t as simple as swapping out a battery. Each module is programmed specifically for the vehicle it came from, accounting for its engine size, transmission type, and other factory options. Simply installing a used computer from another vehicle will almost certainly result in it not working correctly, if at all. Our service eliminates this headache. When you order, you provide us with your vehicle’s VIN. We then flash this genuine used GM PCM with the latest, most up-to-date software directly from GM, ensuring it is a perfect match for your truck’s specific configuration. This makes installation a straightforward process, getting you back on the road without a costly trip to the dealership for programming.
From the Diagnostic Bay
We had a 1999 Chevy Suburban come into the shop with a classic ‘no communication with PCM’ code. The owner had already replaced the module with one from a junkyard, but the truck still wouldn’t start. After an hour of chasing wires, we found the issue wasn’t the PCM itself, but a corroded ground wire on the engine block. These older GM trucks are notorious for it. After cleaning the ground connection, the original PCM started communicating again. The lesson? Always check your main power and ground connections to the PCM before condemning the unit. A simple $5 wire brush can save you hundreds in misdiagnosis.
Signs You Need a 1998-1999 GMC 1500 PCM Replacement
A failing PCM can manifest in various ways. If you’re experiencing any of the following, it’s a strong indication that your engine computer may need to be replaced. Cross-reference these symptoms with diagnostic trouble codes (DTCs) for a more accurate diagnosis.
- ✔ Check Engine Light is on with communication-related codes (U-codes) or internal processor failure codes (P06xx codes).
- ✔ Vehicle fails to start or starts intermittently.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Engine stalling, stuttering, or misfiring for no apparent reason.
- ✔ Failure to pass an emissions test.
Guaranteed Compatibility and Simple Installation
This module is a tested, genuine used part sourced from a salvaged vehicle, ensuring OEM quality and fitment. It is a direct replacement for multiple part numbers, including 09355699, 16266645, 16250279, 16258815, and 09366810. While this listing focuses on the 1998-1999 GMC 1500 PCM, it fits a wide array of Chevrolet and GMC trucks, vans, and SUVs from that era. Please verify your original part number and consult the detailed fitment list to ensure this is the correct component for your vehicle. Installation is typically straightforward, requiring only basic hand tools to disconnect the battery, locate the module in the engine bay, and swap the electrical connectors. In most cases, a security relearn procedure may be necessary, which can be done without special tools and instructions are readily available online.
Frequently Asked Questions
Do I need to send you my old computer?
No, there is no core charge or need to send your old part back to us. This is an outright purchase.
How do I provide my VIN number?
After you complete your purchase, you will receive instructions on how to send us your vehicle’s 17-digit VIN. We cannot program and ship the module until we receive this information.
Is this part difficult to install myself?
For most DIY mechanics, the installation is simple. It involves disconnecting the vehicle’s battery, unplugging the electrical harnesses from the old PCM, unbolting it, and then installing the new one in reverse order. The most critical step is ensuring the battery is disconnected to prevent electrical damage.
Will this fix my vehicle’s problem for sure?
This PCM will fix any issues directly caused by a faulty computer. However, it will not fix problems caused by other bad sensors, wiring faults, or mechanical issues. Proper diagnosis is key to ensuring you are ordering the correct part for your repair.
What is a security relearn procedure?
Many GM vehicles of this era have a PassLock anti-theft system that may need to be synchronized with the new PCM. This is a simple procedure that usually involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Your vehicle’s service manual or a quick online search can provide the exact steps.