Get Your Workhorse Van Running Right Again
Is your 1998 or 1999 GMC Savana 2500 giving you headaches? If you’re dealing with frustrating issues like a no-start condition, erratic engine behavior, poor fuel mileage, or a persistent Check Engine Light, the problem often points directly to a failing Powertrain Control Module (PCM). As the central computer of your vehicle, a faulty PCM can create a cascade of problems that are difficult to diagnose. This isn’t just an inconvenience; it’s a reliability issue that can cost you time and money, especially if you depend on your van for work.
This is a reliable, tested, and genuine GM Powertrain Control Module that offers a direct-fit solution. Forget the exorbitant costs and scheduling hassles of a dealership visit. We take the complexity out of the replacement process. This unit is meticulously sourced from a salvaged vehicle and is ready to be programmed specifically for your van. By providing us with your Vehicle Identification Number (VIN) at checkout, we will flash the module with the latest GM software updates. This ensures it communicates perfectly with your van’s specific systems, restoring its original performance and efficiency. This is the most straightforward way to replace a faulty 1998-1999 Savana 2500 PCM and get back on the road with confidence.
From the Diagnostic Bay
I remember a 1999 Chevy Express 2500 that came into my shop a few years back. The owner had already replaced the fuel pump and filter, chasing an intermittent stalling issue that only happened after it was fully warmed up. No codes were stored, which made it extra tricky. After hooking up my scan tool and monitoring live data, I noticed the injector pulse width would suddenly drop to zero right before it stalled. All sensor inputs looked normal. On a hunch, I gently tapped on the PCM casing with a screwdriver handle, and the engine immediately died. That confirmed it—an internal fault in the PCM was causing a thermal failure. A replacement, programmed PCM like this one had the van running reliably in under an hour. It’s a classic failure mode for these modules.
Is Your Van Exhibiting These Classic PCM Failure Signs?
A failing engine computer can manifest in numerous ways. If you’re experiencing any of the following, a faulty PCM is a likely culprit:
- ✔ Check Engine Light is illuminated with communication-related codes (e.g., P0601, P0605) or random sensor codes.
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling, especially after the engine has warmed up.
- ✔ Noticeably poor fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to pass an emissions or smog test.
A Straightforward Guide to Installation
Installing your replacement 1998-1999 Savana 2500 PCM is a job most DIYers can handle with basic tools. Since we program it beforehand, you won’t need a trip to the dealer.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most Savana and Express vans, the PCM is located in the engine compartment, typically on the driver’s side near the battery or on the firewall.
- Disconnect the Connectors: Carefully unclip the wiring harness connectors from the old PCM. There are usually several large, multi-pin connectors with locking tabs. Be gentle to avoid damaging the pins or clips.
- Remove the Old Module: Unbolt the PCM from its mounting bracket. Keep the hardware, as you may need to reuse it.
- Install the New Module: Bolt the new, pre-programmed PCM into place and securely reconnect the wiring harnesses. You should hear a ‘click’ as they lock in.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Perform Security Relearn: You will need to perform a security relearn procedure (often called a CASE relearn or Passlock relearn). This simple process involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times. This allows the new PCM to synchronize with your vehicle’s anti-theft system. Afterwards, the vehicle should start and run normally.
Verified Vehicle Compatibility
This module, identified by part number 16258815 or service ID 9355699, is a direct replacement for a wide range of GM trucks and vans. While this is a 1998-1999 Savana 2500 PCM, please verify your part number or consult the list below to ensure a perfect match for your vehicle. This part is compatible with the following part numbers: 09355699, 16266645, 16250279, 09366810, 9366810.
This module fits many 1998-1999 GM models, including:
- ✔ Chevrolet Express & GMC Savana Vans (1500, 2500, 3500)
- ✔ Chevrolet & GMC Pickups (1500, 2500, 3500)
- ✔ Chevrolet Suburban & Tahoe
- ✔ GMC Yukon & Yukon XL
- ✔ Cadillac Escalade
- ✔ Chevrolet Astro & GMC Safari
- ✔ Chevrolet S10, GMC Sonoma, Oldsmobile Bravada, Isuzu Hombre (4.3L V6 models)
Always match the ID number (9355699) on your original computer to ensure 100% compatibility.
Frequently Asked Questions
Do I need to do anything after I install this PCM?
Yes. Although we program the module to your VIN, you will need to perform a security relearn procedure (sometimes called Passlock or CASE relearn). This is a simple procedure that takes about 30 minutes and involves cycling the ignition key. Instructions are readily available online for your specific model, or we can provide guidance.
What information do you need from me?
After you complete your purchase, you must provide us with your 17-digit Vehicle Identification Number (VIN). We cannot ship your part until we have this information, as it is required to program the module correctly for your vehicle’s options and software.
Is this a new part?
No, this is a thoroughly tested, used OEM (Original Equipment Manufacturer) part that was sourced from a salvaged vehicle. This allows us to offer a reliable, factory-quality part at a significant cost saving compared to a new unit from a dealer.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls both engine and transmission functions. If the module is failing, it can cause erratic shifting, delayed engagement, or incorrect gear selection. Replacing a faulty PCM often resolves these types of transmission issues.
What is the difference between a PCM and an ECM?
The terms are often used interchangeably. ECM stands for Engine Control Module, while PCM stands for Powertrain Control Module. A PCM is an ECM that also controls the transmission and other powertrain components. For these GM vehicles, PCM is the more accurate term.