Restore Peak Performance to Your GM Truck or Van
Is your trusty 1998-1999 Chevrolet 1500 Pickup suddenly stalling, running rough, or refusing to start? Are you chasing frustrating, intermittent electrical gremlins? Before you start throwing expensive parts at it, the problem is very likely the heart of your vehicle’s electronics: the Powertrain Control Module (PCM). As a technician with over two decades of experience, I’ve seen firsthand how a failing PCM can cause a cascade of issues that seem unrelated. This isn’t just a part; it’s the solution to getting your reliable workhorse back on the road with confidence.
This is a genuine, road-tested used PCM that we flash with the latest official GM software updates specific to your vehicle. By providing your Vehicle Identification Number (VIN) at checkout, you receive a module that is 100% plug-and-play. We handle the complex programming, saving you a costly trip to the dealership and the headache of incompatible software. This is the most direct and effective way to solve complex engine management problems for your 1998-1999 Chevrolet 1500 PCM.
From the Diagnostic Bay: The Case of the Ghostly Stall
I remember a ’99 GMC Sierra that came into my shop. The owner was at his wit’s end. He’d replaced the fuel pump, plugs, and wires, but the truck would still stall randomly at stoplights, especially after it was fully warmed up. No specific codes were stored, just a generic history. After hooking up my diagnostic scanner and monitoring live data, I noticed the injector pulse width would erratically drop out just before a stall. This pointed away from the fuel system and towards the driver—the PCM. The internal board was failing under heat. We installed a VIN-programmed PCM just like this one, and the truck ran perfectly. It’s a classic failure mode for these modules, and this part is the definitive fix.
Is Your GM Truck Showing These Signs of PCM Failure?
- ✔ Unexplained Check Engine Light (CEL) illumination, often with codes like P0601 or P0605.
- ✔ Engine stalling, stumbling, or hesitating, particularly when warm.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A complete no-start condition where the engine cranks but won’t fire.
- ✔ Poor fuel economy and a noticeable loss of power.
- ✔ Issues with the anti-theft system (Passlock/VATS) engaging incorrectly.
A Straightforward Guide to Installation
You don’t need to be a master mechanic to install this module. Since we program it to your VIN, the hard part is already done. Just follow these simple steps.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- Locate the PCM: On most 1998-1999 GM trucks and vans, the PCM is located in the engine bay, typically on the driver’s side fender well, housed in a black plastic bracket.
- Disconnect the Connectors: Carefully unclip and remove the large wiring harness connectors from the old PCM. They are color-coded and can only fit in their correct slots.
- Swap the Module: Unbolt the old PCM from its mounting bracket and remove it. Place the new, pre-programmed module into the bracket and secure it.
- Reconnect Everything: Firmly plug the wiring harnesses into the new PCM. Reconnect the negative battery terminal.
- Perform Security Relearn: You MUST perform the vehicle’s security relearn procedure to sync the new PCM with your keys. See our FAQ below for the simple, 30-minute key-cycle procedure. Your vehicle will not start until this is completed.
Verified Fitment For Your GM Truck or Van
This module is a direct replacement for service numbers 16266645 and 09355699, and also interchanges with 16250279, 16258815, 09366810, and 9366810. It is guaranteed to fit a wide range of 1998-1999 GM vehicles, including but not limited to:
- ✔ Chevrolet & GMC 1500/2500/3500 Pickups (Gasoline)
- ✔ Chevrolet Tahoe & GMC Yukon (Gasoline)
- ✔ Chevrolet & GMC Suburban (Gasoline)
- ✔ Chevrolet Express & GMC Savana Vans (Gasoline)
- ✔ Cadillac Escalade (1999)
- ✔ Chevrolet Astro & GMC Safari
- ✔ Oldsmobile Bravada, Chevrolet S10 Blazer, GMC S15 Jimmy, Isuzu Hombre (4.3L V6 models)
Please ensure your original module has one of the compatible part numbers listed to guarantee a perfect match.
Why do you need my Vehicle Identification Number (VIN)?
Why do you need my Vehicle Identification Number (VIN)?
Your VIN is essential for us to program the PCM with the correct software for your truck’s specific engine, transmission, and emissions equipment. This ensures seamless communication between all vehicle systems and guarantees a true plug-and-play installation without needing a dealership visit.
What is the security relearn procedure?
It’s a simple process to sync the new PCM with your vehicle’s anti-theft system. 1) Turn the key to the ‘ON’ position (don’t start) for 10 minutes, until the security light turns off. 2) Turn the key ‘OFF’ for 10 seconds. 3) Repeat this cycle two more times for a total of three 10-minute cycles. After the third cycle, the vehicle will be ready to start.
Is any other programming required after I install it?
No. Our service includes loading all the necessary GM operational software. The only procedure you need to perform is the security relearn, which requires no special tools. Some models may also require a Crankshaft Position Sensor (CASE) relearn for optimal performance, which can be done by most local repair shops with a capable scan tool.
Since this part is from a salvaged vehicle, how can I trust it?
We source our modules from trusted salvage suppliers and each one undergoes a thorough inspection and testing process before being programmed and shipped. By using an authentic GM part, you maintain the original engineering and reliability, and our VIN-programming service ensures it functions as new for your specific vehicle.