Restore Peak Performance to Your GM Truck or Van
Is your trusty Chevrolet 2500, Express Van, or another GM vehicle from this era suddenly running rough, refusing to start, or throwing confusing check engine light codes? As a technician with over two decades of experience under the hood, I’ve seen these symptoms countless times. The Powertrain Control Module (PCM), the electronic brain of your vehicle, is often the culprit. When it fails, it can cause a cascade of frustrating and hard-to-diagnose problems. This isn’t just a part; it’s the central command for your engine and transmission, and getting it right is critical.
We offer a dependable and straightforward solution: a replacement PCM, part number 8162634940, that arrives at your door fully programmed to your vehicle’s specific Vehicle Identification Number (VIN). We flash it with the latest official GM software updates, which can resolve factory-known bugs and improve overall performance and efficiency. This eliminates the need for expensive dealership visits or specialized programming tools, making it a perfect fix for both professional mechanics and dedicated DIYers.
From the Diagnostic Bay: The Case of the Intermittent Stall
A customer brought in his ’99 GMC Sierra 1500 with a problem that was driving him crazy. It would run perfectly for days, then suddenly stall at a stoplight and refuse to restart for 10-15 minutes. No consistent codes, just pure frustration. We checked fuel pressure, spark, and sensors—all looked good. From experience, I know these intermittent thermal failures are classic signs of a dying PCM. The internal solder joints and processors get brittle over 20+ years of heat cycles. We swapped in a VIN-programmed PCM like this one, and the problem vanished instantly. He saved hundreds on diagnostic time and got his reliable truck back.
Is Your GM Truck Showing These Signs of a Bad PCM?
A failing engine computer can manifest in many ways. If you’re experiencing any of the following, a faulty PCM is a likely cause. Look out for:
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- ✔ Engine cranks but refuses to start (no-start condition).
- ✔ Rough or erratic idling and stalling.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ Communication errors with your scan tool.
A Straightforward Guide to Installation
Replacing the PCM on these GM vehicles is a manageable job for most DIYers. Follow these steps to ensure a smooth installation. The key is to have your VIN-programmed module ready to go!
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental contact.
- Locate the PCM: On most trucks like the Chevrolet 2500 Pickup, the PCM is located in the engine compartment on the driver’s side (LH), often near the battery or on the inner fender. On vans like the Express/Savana, it’s typically in the LH rear of the engine compartment.
- Disconnect the Harnesses: Carefully unclip and remove the electrical wiring harnesses connected to the old PCM. These connectors have locking tabs that need to be released before pulling. Avoid forcing them.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware, as you may need to reuse it.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and securely reconnect the wiring harnesses. You should hear a ‘click’ as they lock into place.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Perform Security Relearn (If Necessary): While this module is programmed, some GM vehicles require a security relearn procedure to sync the new PCM with the anti-theft system. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Check your vehicle’s specific procedure.
Verified Fitment for Your GM Truck or Van
This module is a direct replacement for several part numbers, including 16263494, 16265035, and 218-11787. It is guaranteed to be compatible with the following vehicles, provided the options match. Please verify your original part number or contact us with your VIN if you are unsure.
CHEVROLET 1500/3500 PICKUP 99-00 (Gasoline)
SILVERADO 1500 PICKUP 99-00 (4.3L V6)
GMC 1500/2500/3500 PICKUP 99-00 (Gasoline)
SIERRA 1500 PICKUP 99-00 (4.3L V6)
CHEVY EXPRESS 1500/2500/3500 VAN 99-02 (Gasoline)
GMC SAVANA 1500/2500/3500 VAN 99-02 (Gasoline)
CHEVY ASTRO / GMC SAFARI 99-01 (4.3L)
CHEVY BLAZER S10 / GMC JIMMY S15 98-00
CHEVY S10 / GMC SONOMA 98-00 (4.3L)
OLDSMOBILE BRAVADA 98-00
GMC ENVOY 98-00
CADILLAC ESCALADE 99-00
CHEVY TAHOE 99-00 (Classic Style)
GMC YUKON / YUKON DENALI 99-00
CHEVY SUBURBAN 1500/2500 99 (Gasoline)
ISUZU HOMBRE 98-00 (4.3L)
Frequently Asked Questions
How do I provide my VIN for programming?
After completing your purchase, please send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot ship your order until we receive this information, as programming is essential for the part to function correctly in your vehicle.
Is any additional programming required after installation?
In most cases, no. The PCM arrives pre-programmed to your VIN. However, on some vehicles, a security relearn or a Crankshaft Position Sensor (CASE) relearn may be necessary. The security relearn can often be done without special tools, but a CASE relearn requires a capable bi-directional scan tool.
What’s the difference between a PCM and an ECM?
The terms are often used interchangeably. ECM stands for Engine Control Module, while PCM means Powertrain Control Module. A PCM is an ECM that also controls the transmission and other powertrain functions, which is standard on most vehicles this part fits.
Why is a VIN-programmed module better than one from a salvage yard?
A salvage yard part will be programmed to the donor vehicle’s VIN and options, which will almost certainly cause compatibility issues, no-start conditions, or trigger the anti-theft system in your truck. Our modules are programmed specifically for YOUR vehicle and have the latest software, ensuring a reliable, long-term fix.
Does this part come with a warranty?
Yes, all of our electronic modules are thoroughly tested and come with a warranty. Please see the warranty tab on the listing for complete details and feel confident in your purchase.