Restore Peak Performance to Your GM Truck or Van
Is your Chevrolet Astro, S10, Express van, or other GM vehicle suffering from perplexing issues like a persistent check engine light, erratic shifting, poor fuel mileage, or a no-start condition? The Powertrain Control Module (PCM), often called the vehicle’s brain, is frequently the source of these frustrating problems. This replacement PCM, part number 218-11787, is the definitive solution to restore your vehicle’s factory performance, drivability, and reliability. It arrives at your door fully programmed to your specific Vehicle Identification Number (VIN), ensuring a seamless installation process.
We take the guesswork and additional expense out of the repair. Simply provide your VIN after purchase, and our technicians will flash the module with the latest GM-certified software updates for your exact vehicle. This ensures all engine and transmission parameters are set correctly, eliminating the need for a costly trip to the dealership for programming.
From the Diagnostic Bay
We once had a 2000 Chevy Blazer come in that was driving the owner crazy. He had replaced the spark plugs, wires, cap, rotor, and even a couple of sensors trying to chase down a random misfire code (P0300) and a harsh 1-2 shift. The parts cannon wasn’t working. After hooking up our diagnostic scanner, we noticed the PCM was slow to respond and was dropping communication intermittently. We installed one of our pre-programmed modules, performed a quick CASE relearn, and the truck ran like it just rolled off the assembly line. The owner was thrilled to finally have a reliable vehicle again after weeks of chasing ghosts. Sometimes, the problem lies with the computer itself.
Common Symptoms of a Failing 1999-2001 Astro PCM
A failing PCM can manifest in numerous ways, often mimicking other component failures. If you’re experiencing any of the following, it’s a strong indicator that your engine computer may need replacement:
- ✔ Check Engine Light: A constant or intermittent Check Engine Light (CEL) is the most common sign, especially with communication-related codes (U-codes) or multiple, seemingly unrelated trouble codes.
- ✔ Engine Performance Issues: This includes rough idling, stalling, hesitation during acceleration, reduced power, and a noticeable decrease in fuel economy.
- ✔ Transmission Problems: The PCM also controls transmission functions. A bad module can cause harsh shifting, delayed engagement into gear, or getting stuck in one gear (limp mode).
- ✔ No-Start Condition: The engine may crank but refuse to start. This can be caused by the PCM failing to command the fuel pump or ignition system to operate.
- ✔ Failed Emissions Test: An improperly functioning PCM can prevent the vehicle’s emissions systems from running their self-checks, leading to an automatic failure at the inspection station.
Plug-and-Play Installation Process
Because this module is programmed to your VIN before shipping, the physical installation is straightforward. Simply disconnect the battery, locate your old PCM (often near the battery or on the firewall), unplug the electrical connectors, unbolt the module, and install the new one in its place. After reconnecting everything, your vehicle should start and run. Please Note: For many GM vehicles of this era, a Crankshaft Variation Relearn (also known as a CASE relearn) is required after installation to prevent a P1336 trouble code and ensure accurate misfire detection. This procedure can be completed with most professional-grade scan tools.
This module is a direct replacement for OEM part numbers 16263494, 16265035, and 8162634940 and fits a wide variety of GM vehicles. Please verify your part number and consult the detailed fitment list to ensure compatibility.
Frequently Asked Questions
Do I need to program this module?
No. We program the module to your vehicle’s specific VIN before we ship it to you. It arrives ready for installation. Just be sure to provide your VIN after placing your order.
What is a CASE Relearn and is it required?
A CASE (Crankshaft Angle Sensor Error) Relearn is a procedure that calibrates the PCM to the minor variations in the crankshaft position sensor. It is highly recommended after PCM replacement on these GM vehicles to prevent a P1336 trouble code and ensure the engine runs smoothly. Most repair shops can perform this procedure in a few minutes.
Where is the PCM located on my 1999 Astro Van?
On the 1999-2001 Chevrolet Astro and GMC Safari, the PCM is typically located in the engine compartment on the driver’s side, near the battery. On other compatible vehicles like the S10/Blazer, it’s often on the passenger side firewall.
How do I find my vehicle’s VIN?
Your 17-digit VIN can be found on a plate on the driver’s side of the dashboard (visible through the windshield), on the driver’s side door jamb sticker, and on your vehicle’s registration and insurance documents.
Will this fix my vehicle’s specific problem?
This PCM will resolve any issues directly caused by a faulty original module. While it corrects a wide range of common symptoms, it’s essential to ensure your vehicle has been properly diagnosed, as other failing sensors or wiring issues can cause similar symptoms.