Is Your Late 90s GM Truck or Van Running Poorly?
If you’re dealing with a persistent check engine light, stalling, rough idling, or a no-start condition in your 1998-1999 GM vehicle, a failing Powertrain Control Module (PCM) is a very likely culprit. The PCM is the electronic brain of your vehicle, managing everything from fuel injection and spark timing to transmission shifting. When it starts to fail, it can cause a cascade of frustrating and hard-to-diagnose problems that can leave you stranded.
Don’t keep throwing parts at the problem. This is a direct-replacement, used OEM engine computer, part number 9355699, that has been meticulously tested and is ready to be programmed specifically for your vehicle. We take the guesswork out of the repair by flashing the module with the latest official GM software updates using your vehicle’s unique VIN. This ensures that once installed, it communicates perfectly with all the other modules in your truck or van, restoring its original performance and reliability.
From the Diagnostic Bay
I once had a ’99 Chevy Suburban in the shop that was driving the owner crazy. It would randomly stall at stoplights and had a rough idle that no one could fix. He had already replaced the fuel pump, spark plugs, and even the mass airflow sensor. The codes were intermittent and pointed towards a communication error. We suspected the PCM. After installing one of these VIN-programmed units, the truck immediately fired up and idled perfectly. The owner was thrilled to have his reliable workhorse back. It’s a classic case where the central computer was the root cause, not the individual components it controls.
The Right Solution: A Programmed GM PCM 9355699
This isn’t just a part in a box; it’s a complete solution. Sourced from a salvaged vehicle, this genuine GM module offers the durability and compatibility that aftermarket units often lack. The critical step is our programming service. Before we ship the PCM to you, our technicians will use your VIN to load the exact software calibration your vehicle needs. This process is essential for:
- Proper Engine and Transmission Function: Ensures fuel maps, shift points, and ignition timing are correct for your specific engine and drivetrain.
- Anti-Theft System Compatibility: Allows the PCM to correctly handshake with your vehicle’s security system, preventing a no-start situation after installation.
- Emission Control Compliance: Guarantees all emissions-related parameters are set to factory specifications.
- Plug-and-Play Installation: Eliminates the need for an expensive trip to the dealership for programming. While a simple security relearn or CASE relearn may be required, the core programming is done.
Common Symptoms of a Failing PCM:
- ✔ Persistent Check Engine Light (CEL) with communication-related trouble codes (e.g., U-codes).
- ✔ Engine stalling for no apparent reason, either while driving or at idle.
- ✔ Rough, erratic, or surging idle.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or delayed transmission shifting.
- ✔ Misfire codes that don’t resolve after replacing plugs, wires, or coils.
- ✔ Complete engine no-start, even with a good battery and starter.
Replacing your faulty module with our pre-programmed GM PCM 9355699 is the most effective way to solve these issues and restore your vehicle’s factory operation. Simply provide your VIN during checkout, and we’ll handle the rest, shipping you a part that’s ready for installation.
Frequently Asked Questions
What information do you need from me to program the PCM?
We require your vehicle’s 17-digit Vehicle Identification Number (VIN). You can typically find this on your driver’s side dashboard (visible through the windshield), on the driver’s door jamb sticker, or on your vehicle’s registration and insurance documents.
Is this part truly ‘plug and play’?
For most vehicles, it is. The main programming is completed by us. However, on many GM vehicles of this era, you may need to perform a security relearn procedure, which can often be done without special tools. A Crankshaft Variation Relearn (CASE relearn) may also be necessary with a capable scan tool to ensure optimal performance and eliminate certain trouble codes. This is standard for any PCM replacement.
Is this a new computer?
No, this is a genuine, used OEM computer that has been carefully removed from a salvaged vehicle. We test all units to ensure they are fully functional before programming and shipping.
My old computer has a different part number. Will this still work?
This module, ID 9355699, is a direct replacement for several other part numbers including 16266645, 16250279, 16258815, and 09366810. Please check the fitment list on this page to confirm compatibility with your specific make, model, and year.
Where is the PCM located on my vehicle?
On most of the compatible trucks, SUVs, and vans, the PCM is located in the engine compartment, typically on the driver’s side near the battery or firewall.