Restore Your Van’s Reliability and Performance
As a technician with over two decades of experience under the hood, I know how frustrating it is when your workhorse van is down. Whether it’s a no-start condition that leaves you stranded, a rough idle that shakes the whole vehicle, or a mysterious Check Engine Light that won’t go away, a faulty Powertrain Control Module (PCM) is often the culprit. These late-90s GM vehicles are known for their durability, but the electronics can eventually fail. This isn’t just an inconvenience; it’s lost time and money. That’s why we offer a straightforward, reliable solution: a quality-tested, used 1998-1999 Express 2500 PCM, programmed specifically for your vehicle.
Forget the hassle and high cost of a dealership visit. We take a genuine, salvaged GM PCM and flash it with the latest official GM software updates using your van’s unique Vehicle Identification Number (VIN). This ensures that all parameters—from fuel delivery and ignition timing to transmission shift points—are perfectly matched to your vehicle’s original specifications. It’s the smart, efficient way to get your van back on the road and running like it should.
Case Study: A Tricky Diagnosis
I remember a 1999 Savana 2500 that came into my shop with a complaint of intermittent stalling at stoplights. The owner had already replaced the fuel pump and idle air control valve with no luck. There were no consistent trouble codes, making it a real head-scratcher. After checking all the wiring and grounds, I hooked up my scope to the injector drivers at the PCM. I noticed that the signal for cylinder 3 would drop out randomly just before the engine would stumble. It was a classic case of an internal PCM driver failing under heat soak. We swapped in a VIN-programmed PCM like this one, and the van ran flawlessly. It’s a reminder that sometimes the ‘brain’ is the source of the most elusive problems.
Is Your Van Showing These Symptoms?
- ✔ Check Engine Light is illuminated with codes like P0601 (Internal Memory Error) or P0606 (PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel economy.
- ✔ Rough or erratic idling and stalling.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ Your vehicle fails an emissions test.
- ✔ Loss of communication with the PCM when using a scan tool.
A Straightforward Guide to Installation
Replacing your 1998-1999 Express 2500 PCM is a job most DIYers can handle in under an hour. You don’t need specialized tools, just basic hand tools and a little patience.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most Express and Savana vans, the PCM is located in the engine compartment on the driver’s side, near the battery or firewall.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old PCM. These connectors are color-coded, making re-installation simple. Inspect them for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and securely tighten the bolts.
- Reconnect Everything: Plug the wiring harnesses back into the correct slots on the new PCM. You’ll hear a click when they are properly seated. Reconnect the negative battery terminal.
- Final Steps: In some cases, a security relearn procedure (often called Passlock or Passkey) may be required. This is a simple process that typically involves turning the key to the ‘ON’ position for 10-15 minutes. A Crankshaft Variation (CASE) relearn might also be needed with a capable scan tool to clear a P1336 code, though the vehicle will often run fine without it.
Verified Vehicle Compatibility
This module is a direct replacement for service number 09366810 and is interchangeable with part numbers 09355699, 16266645, 16250279, and 16258815. It is guaranteed to fit the following vehicles (when matching ID 9355699):
- ✔ 1998-1999 Chevrolet & GMC 1500/2500/3500 Pickups (Gasoline)
- ✔ 1998-1999 Chevrolet Express & GMC Savana 1500/2500/3500 Vans (Gasoline)
- ✔ 1998-1999 Chevrolet Suburban 1500/2500 (Gasoline)
- ✔ 1998-1999 Chevrolet Tahoe & GMC Yukon
- ✔ 1999 Cadillac Escalade
- ✔ 1998 Chevrolet Astro & GMC Safari
- ✔ 1998 Oldsmobile Bravada (4.3L)
- ✔ 1998 Chevrolet S10, GMC Sonoma, Isuzu Hombre (4.3L)
- ✔ 1998 Chevrolet Blazer & GMC Jimmy (4.3L)
- ✔ 1998 Oldsmobile Envoy (4.3L)
Solving your van’s engine problems doesn’t have to be complicated or expensive. With our pre-programmed 1998-1999 Express 2500 PCM, you get a reliable part that’s ready for installation right out of the box. Place your order, provide your VIN, and get back to work with confidence.
Frequently Asked Questions
What is VIN programming and why do I need it?
VIN programming involves loading your vehicle’s specific software onto the PCM. This ensures the engine, transmission, and anti-theft systems all function correctly according to GM’s original specifications for your exact van. It makes the part truly plug-and-play.
Is this part difficult to install myself?
Not at all. For most DIYers with basic hand tools, this is a simple, one-hour job. You just need to disconnect the battery, unbolt the old unit, and plug in the new one. See our installation guide above for step-by-step instructions.
How do I provide my VIN number?
After you complete your purchase, you will receive instructions on how to send us your 17-digit VIN. We cannot ship your part until we receive this information, as the programming is essential for the part to work.
Will I need to do anything after installing the PCM?
In many cases, the vehicle will start and run perfectly after installation. Occasionally, a simple security relearn procedure is needed, which involves leaving the key in the ‘ON’ position for about 10-15 minutes. A professional mechanic may also recommend a CASE relearn to optimize engine timing, but it is not always required for the vehicle to run properly.
Is this a new part?
No, this is a high-quality, tested computer that was sourced from a salvaged vehicle. We inspect and verify each unit for full functionality before programming and shipping it to you, offering a reliable and cost-effective alternative to a new dealer part.