Restore Your Van’s Performance with a Reliable, Programmed Engine Computer
As a technician with over two decades of experience under the hood, I’ve seen firsthand the headaches a failing Powertrain Control Module (PCM) can cause. Your 1998-1999 Chevy Express or GMC Savana is a workhorse, but when its electronic brain starts acting up, you’re faced with frustrating problems like stalling, no-start conditions, erratic shifting, and a persistent Check Engine Light. Finding a reliable and affordable fix can feel like a dead end, especially with dealerships charging a fortune for a new part and programming.
This is the solution you’ve been looking for. This is a genuine, road-tested PCM, part number 9355699, sourced from a salvaged vehicle. The real value here is our in-house programming service. Before this module ships, we flash it with the latest GM software updates, specifically matched to your vehicle’s VIN. This means it arrives at your door ready for installation, with no need for expensive trips to the dealer or special scan tools. It’s the most direct path to getting your van or truck running smoothly again.
From the Diagnostic Bay
I remember a 1999 Suburban that came into the shop with the weirdest issue. The owner said it would randomly refuse to start, but only after it was warm. No codes, no obvious faults. We checked fuel pressure, spark, and wiring for hours. On a hunch, I tapped the PCM casing with a screwdriver handle while my apprentice cranked the engine, and it fired right up. The internal processor was failing under heat stress—a classic sign of age. We swapped in a pre-programmed module just like this one, and the customer called a week later to say his truck had never run better. These intermittent faults are often the first sign of a failing 1998-1999 Express 1500 PCM.
Is Your GM Vehicle Showing These Symptoms?
A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, this module is a likely solution:
- ✔ Unexplained Check Engine Light with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
- ✔ Engine stalling, sputtering, or refusing to start.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Poor fuel economy and a noticeable loss of power.
- ✔ Communication errors with diagnostic scan tools.
- ✔ Seemingly random electrical issues affecting gauges or other systems.
A Straightforward Guide to PCM Installation
One of the biggest benefits of this module is its simple installation. Since we handle the programming, you can perform the swap yourself with basic hand tools.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most of these GM trucks and vans, the PCM is located in the engine compartment, typically on the driver’s side fender well or near the battery.
- Disconnect the Connectors: Carefully unclip the wiring harness connectors from the old PCM. They have locking tabs, so be gentle to avoid damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket.
- Install the New Module: Bolt your new, pre-programmed PCM into place.
- Reconnect Everything: Firmly plug the wiring harnesses into the new module until they click. Reconnect the negative battery terminal.
- Final Step: Your vehicle may require a security relearn procedure, which is a simple process you can do yourself (instructions are readily available online or we can provide them). Then, start the engine and enjoy a smoother-running vehicle!
Verified Vehicle Compatibility
This PCM, identified by service number 9355699, is a direct replacement for a wide range of GM vehicles. Please verify your original part number or match your vehicle from the list below. This part is interchangeable with numbers: 09355699, 16266645, 16250279, 16258815, 09366810, and 9366810.
BLAZER S10/JIMMY S15 98: (RH front engine compartment), w/o build date opt ZN4; ID 9355699
BRAVADA 98: (6-262, 4.3L), w/o build date opt ZN4; ID 9355699
CHEVROLET 1500 PICKUP 98-99: gasoline (LH front engine compartment), ID 9355699
CHEVROLET 2500 PICKUP 98-99: gasoline (LH front engine compartment), ID 9355699
CHEVROLET 3500 PICKUP 98-99: gasoline (LH front engine compartment), ID 9355699
ENVOY 98: (RH front engine compartment), w/o build date opt ZN4; ID 9355699
ESCALADE 99: (LH front engine compartment), ID 9355699
EXPRESS 1500 VAN 98-99: ID 9355699
EXPRESS 2500 VAN 98-99: gasoline, ID 9355699
EXPRESS 3500 VAN 98-99: gasoline, ID 9355699
GMC 1500 PICKUP 98-99: gasoline (LH front engine compartment), ID 9355699
GMC 2500 PICKUP 98-99: gasoline (LH front engine compartment), ID 9355699
GMC 3500 PICKUP 98-99: gasoline (LH front engine compartment), ID 9355699
ISUZU HOMBRE 98: 4.3L, w/o extended build date opt ZN4; ID 9355699
S10/S15/SONOMA 98: 6-262 (4.3L), w/o build date opt ZN4; ID 9355699
SAFARI (GMC) 98: (LH front by battery), ID 9355699
SAVANA 1500 VAN 98-99: ID 9355699
SAVANA 2500 VAN 98-99: gasoline, ID 9355699
SAVANA 3500 VAN 98-99: gasoline, ID 9355699
SUBURBAN 1500 98-99: gasoline (LH front engine compartment), ID 9355699
SUBURBAN 2500 98-99: gasoline (LH front engine compartment), ID 9355699
TAHOE 98-99: gasoline (LH front engine compartment), ID 9355699
YUKON 98-99: (LH engine compartment), ID 9355699
Choosing this tested and correctly programmed 1998-1999 Express 1500 PCM is the smart, reliable way to solve complex drivability problems and get your vehicle back to factory-spec operation without the hassle.
Frequently Asked Questions
What information do you need from me?
After you complete your purchase, we require your vehicle’s 17-digit VIN (Vehicle Identification Number) to program the module correctly. You can usually find this on your dashboard, driver’s side door jamb, or on your vehicle’s registration.
Is this a new part?
No, this is a high-quality, tested used part that has been sourced from a salvaged vehicle. Every module is inspected and verified to be fully functional before being programmed and shipped.
Do I need to do any additional programming after I install it?
No. We handle all the necessary programming based on your VIN before we ship it. The only thing you may need to do is a simple security relearn procedure, which doesn’t require any special tools.
Will this fix my Check Engine Light?
If the Check Engine Light is caused by an internal failure of your original PCM (like a P0601 code), then yes, this part will resolve the issue. It’s crucial to ensure your vehicle’s issues have been correctly diagnosed as a PCM fault.
Why choose a used, programmed PCM over other options?
This option provides the best balance of value and convenience. It’s significantly more affordable than a new module from a dealer and saves you the time, cost, and hassle of getting it programmed separately. It’s a direct, ready-to-install solution.