Is Your GM Truck or Van Running Rough?
If your 1998-1999 Chevrolet Express 1500 is suffering from baffling issues like a persistent check engine light, erratic shifting, a no-start condition, or poor fuel economy, the problem often points directly to a failing Powertrain Control Module (PCM). As the electronic brain of your vehicle, when the PCM starts to fail, it can cause a cascade of problems that are frustrating and difficult to diagnose. I’ve seen it hundreds of times in my shop: a work van that’s losing the owner money every day it’s down, all because of a faulty computer.
Real-World Scenario: A customer’s ’99 Chevy 2500 pickup came in last week with these exact symptoms. It would crank but not start intermittently, and when it did run, the transmission would slam into gear. The scanner was throwing a mix of communication and sensor codes that made no sense together. This is a classic sign of a failing PCM processor. We installed one of our VIN-programmed modules, and the truck fired right up and ran perfectly, with smooth shifts and no more codes. This is the simple, effective fix you’re looking for.
The Direct Solution: A VIN-Programmed 1998-1999 Express 1500 PCM
This isn’t just a used part pulled from a shelf. This is a reliable, tested OEM Powertrain Control Module that we program specifically for your vehicle using your VIN. This critical step ensures that the computer has the correct software and calibrations for your truck or van’s specific engine, transmission, and options. We load the latest available updates from GM, which can often resolve drivability issues that were present even when the vehicle was newer.
- โ VIN-Specific Programming: We flash the module with your vehicle’s VIN, ensuring 100% compatibility.
- โ Plug-and-Play Installation: No trip to the dealership is required. Once you receive the part, you can install it yourself and get back on the road.
- โ Solves Common Issues: An effective fix for check engine lights, harsh shifting, no-start conditions, and communication errors.
- โ Cost-Effective Repair: Get a reliable, programmed module for a fraction of the cost of a new dealership part.
- โ Broad Compatibility: This module, identified by service number 09355699, directly replaces a wide range of part numbers, including 16258815, 16266645, 16250279, and 9366810.
Simple Installation Guide
Installing your replacement PCM is straightforward. While specific locations vary slightly by model (e.g., LH engine compartment on a Tahoe, by the battery on an Astro), the process is generally the same.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: Find the existing module in your engine bay. It will have several large multi-pin wire harness connectors.
- Disconnect the Harnesses: Carefully release the locking tabs and unplug all electrical connectors from the old PCM.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt your new, pre-programmed PCM into place.
- Reconnect Everything: Firmly plug all wire harness connectors into the new module until they click and lock. Reconnect the negative battery terminal.
- Final Check: Start the vehicle. The check engine light may stay on for a short period as the system performs its self-checks, which is normal.
Expert Pro Tip: Before plugging in your new PCM, take a moment to inspect the pins inside the vehicle’s wire harness connectors. On these workhorse trucks and vans, it’s common for moisture to cause corrosion (a green or white powdery substance). Use a small pick and some electrical contact cleaner to gently clean any corrosion off the pins. A bad connection can mimic a faulty PCM and prevent your new part from working correctly.
Guaranteed Fitment
This module is the correct fit for a massive range of 1998-1999 GM trucks and vans equipped with gasoline engines and matching the service ID 09355699. This includes, but is not limited to, the Chevy/GMC 1500/2500/3500 Pickups, Suburban, Tahoe, Yukon, Express/Savana vans, Astro/Safari, Blazer/Jimmy, S10/Sonoma, Escalade, and more. After purchase, simply provide us with your VIN, and we’ll handle the rest, ensuring you get a part that’s ready to install right out of the box.