Is Your 1999-2000 Sierra 2500 Running Rough?
If your GMC Sierra 2500 is suffering from perplexing issues like stalling, poor fuel economy, erratic shifting, or a persistent Check Engine Light, the culprit is often the very brain of your truck: the Powertrain Control Module (PCM). As the central command center for your engine and transmission, a failing PCM can cause a cascade of problems that are frustrating to diagnose and can leave your reliable workhorse parked on the sidelines. Don’t let a faulty computer dictate your truck’s performance. This direct-fit PCM, part number 19109040, is the definitive solution to restore your vehicle’s factory operation and get you back on the road with confidence.
From the Diagnostic Bay
We had a 2000 Silverado 2500 (which uses the same PCM) come into the shop with a complaint that was driving the owner crazy. The truck would randomly stall at stoplights, but not always. Sometimes it would hesitate badly on acceleration. We checked fuel pressure, scanned for codes (which were intermittent and pointed in multiple directions), and couldn’t find a consistent mechanical fault. After chasing our tails, we hooked up a scope to the PCM outputs and noticed the injector pulse signals would occasionally drop out for a millisecond. It was a classic case of an internal PCM failure that only showed up under specific thermal conditions. Swapping in a properly programmed PCM like this one solved the problem instantly. The customer was thrilled to have his dependable truck back.
Symptoms of a Failing 1999-2000 Sierra 2500 PCM
A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, it’s a strong indicator that your module may need replacement:
- ✔ Persistent Check Engine Light (CEL) with various, often unrelated, trouble codes.
- ✔ Engine stalling or cutting out unexpectedly while driving or at idle.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ The engine cranks but refuses to start (no-start condition).
- ✔ Misfires or rough idling that can’t be traced to spark plugs, coils, or injectors.
- ✔ Failure to pass an emissions test.
The Simple, Reliable Solution: VIN-Programmed and Ready to Install
The biggest hurdle in replacing a modern vehicle’s computer is programming. A PCM from a junkyard or a generic part won’t work, as it isn’t coded to your truck’s specific Vehicle Identification Number (VIN), options, and anti-theft system. This is where our service provides immense value. We eliminate the need for an expensive trip to the dealership. When you order from us, we take your VIN and flash this module with the latest, most stable software updates directly from GM. This ensures that the computer is perfectly matched to your vehicle’s configuration, providing a true plug-and-play installation.
This module is a direct replacement for part numbers 19109040, 09354896, and 9354896, and fits a wide range of GM trucks and performance cars from the era, including the Silverado, Tahoe, Yukon, Suburban, Camaro, and Firebird. Simply provide your VIN at checkout, and we handle the complex part, shipping you a module that is ready to be installed right out of the box. After installation, you may need to perform a simple security relearn procedure, which can be done without any special tools and takes about 30 minutes.
Frequently Asked Questions
Do I need to get this PCM programmed by a dealer?
No. This is the primary benefit of our service. We program the module to your vehicle’s specific VIN before we ship it. It arrives ready to install, saving you time and the high cost of dealership programming.
Where is the PCM located on my 1999-2000 Sierra 2500?
On the 1999-2000 Sierra and Silverado 2500 pickups, the Electronic Control Module (PCM) is located in the engine bay on the driver’s side, underneath the battery tray.
What is the security relearn procedure?
This is a simple procedure required by GM’s PassLock anti-theft system to sync the new PCM with your vehicle. It typically involves turning the key to the ‘ON’ position for 10 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Instructions are readily available online and are easy to follow.
How do I provide my VIN?
After you complete your purchase, you will receive instructions on how to send us your 17-digit VIN. We cannot program and ship your part without it, so please provide it promptly to avoid delays.
Is this compatible with other vehicles?
Yes, this PCM is compatible with a wide range of GM vehicles from approximately 1999-2002, including the Silverado, Suburban, Tahoe, Yukon, Camaro, and Firebird. Please verify your original part number (19109040, 09354896, or 9354896) to ensure an exact match.