Is Your GM Truck or Van Running Rough?
If your 1998-1999 GMC 2500 is suffering from baffling issues like a persistent check engine light, erratic transmission shifting, poor fuel mileage, or even a no-start condition, the problem might be its electronic brain: the Powertrain Control Module (PCM). Over two decades of heat, vibration, and electrical cycles can take their toll on these critical components, leading to frustrating problems that are often difficult to diagnose.
In my 20+ years as a technician, I’ve seen countless GMT400-platform trucks and vans come into the shop with these exact symptoms. A customer’s ’99 Tahoe came in last week stalling at random and throwing a dozen different codes. After confirming the wiring harness and sensors were good, we pinpointed the PCM. The internal processors and solder joints simply wear out, causing intermittent communication failures that can mimic a whole host of other problems. This isn’t just a part; it’s the central command for your vehicle’s performance.
The Simple, Reliable Solution: A VIN-Programmed PCM
Forget the high costs and scheduling hassles of a dealership visit. We offer a dependable, tested, used OEM PCM that arrives at your door programmed and ready for installation. We take the guesswork out of the repair by flashing the module with the latest official GM software updates tailored specifically to your vehicle’s VIN. This ensures all factory parameters for your engine, transmission, and emissions systems are perfectly matched.
- โ VIN Programmed Service: We flash the module with your vehicle’s specific VIN, ensuring 100% compatibility.
- โ Latest GM Software: Your PCM comes loaded with the newest software updates for improved performance and reliability.
- โ Cost-Effective Repair: Get a quality-tested OEM part without the new-part price tag.
- โ Direct Replacement: This module is a direct fit for part numbers like 9366810 and 09355699, among others.
- โ Solve Common Failures: Effectively addresses issues like false sensor codes, harsh shifting, engine stumbling, and communication errors with scan tools.
Expert Pro Tip: Check Your Grounds First!
Before you replace your PCM, take 10 minutes to inspect the main engine ground straps. On these GM trucks and vans, a corroded or loose ground from the engine block to the firewall or frame can cause voltage drops that mimic classic PCM failure symptoms. A simple visual inspection and tightening the bolts can sometimes be the fix. It’s a crucial step I’ve taught every apprentice technician over the years.
Plug-and-Play Installation: No Dealer Visit Required
Installing your new 1998-1999 GMC 2500 PCM is a straightforward job you can do in your own driveway. Follow these simple steps to get your truck back in top shape.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electrical work.
- Locate the PCM: On most 1998-1999 GM trucks and full-size vans, the PCM is located in the engine compartment, typically on the driver’s side inner fender or near the firewall.
- Disconnect Wiring: Carefully release the locking tabs and unplug the multi-pin wiring harness connectors from the old module. Inspect the pins for any signs of corrosion or damage.
- Remove Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install New Module: Secure your new, programmed PCM onto the bracket and firmly plug in the wiring connectors until they click into place.
- Reconnect Battery: Reattach the negative battery terminal and tighten it securely.
- Security Relearn Procedure: Your vehicle may need to relearn the Passlock security system. This is a simple process: Turn the key to the ‘ON’ position (don’t start the engine) for 10-15 minutes, or until the ‘Security’ light stops flashing. Turn the key off for 10 seconds. Repeat this cycle two more times. The vehicle should then start and run normally.
Guaranteed Fitment
This PCM is a direct replacement for multiple GM part numbers, including 09355699, 16266645, 16250279, 16258815, and 09366810. It fits a wide range of GM vehicles from 1998-1999, including the Chevrolet/GMC C/K 1500, 2500, 3500 pickups, Suburban, Tahoe, Yukon, Express, Savana, and more. Please verify your part number or contact us with your VIN to confirm compatibility. By ordering from us, you’re getting a part that’s not only tested but also correctly configured for a seamless repair.