Get Your GM Truck Running Right Again
If you’re dealing with baffling engine problems in your 1998-1999 Chevrolet Suburban 1500—like stalling, rough idling, no-start conditions, or a check engine light that won’t quit—you’ve likely pinpointed the culprit: a failing Powertrain Control Module (PCM). As a technician with over two decades of experience, I’ve seen firsthand how a faulty PCM can cause a cascade of frustrating, hard-to-diagnose issues. It’s the brain of your vehicle, and when it’s not working correctly, nothing else will.
This isn’t just a replacement part; it’s a direct solution. We are offering a reliable, tested, and pre-programmed OEM PCM with the service number 9355699. Pulled from a salvaged vehicle, each unit is inspected for integrity. The real value comes from our in-house programming service. Before we ship it, we flash the module with the latest GM-authorized software updates, specifically matched to your vehicle using your VIN. This means you get a component that’s ready to install right out of the box, eliminating the need for an expensive trip to the dealership for programming.
A Technician’s Notebook: The Case of the Intermittent Stall
I once had a ’99 Tahoe in the bay that would die randomly at stoplights. No codes, no warning. The owner had already replaced the fuel pump and ignition coil. After checking all the vitals, I suspected the PCM. On these older GMT400 platforms, the internal solder joints on the PCM board can develop micro-fractures from years of heat cycles and vibration. This causes intermittent connection loss that won’t always set a trouble code. Swapping in a known-good, correctly programmed PCM like this one solved the problem instantly. It’s a classic failure mode I’ve diagnosed hundreds of times.
Is Your Truck Showing These Telltale Signs?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, this module is the likely solution for your 1998-1999 Suburban 1500 PCM issues.
- ✔ Check Engine Light is on with codes related to internal module failure (like P0601, P0604, or P0606).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling or rough, erratic idling.
- ✔ Poor fuel economy and noticeable loss of power.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ Communication errors with your diagnostic scan tool.
A Straightforward Guide to Your PCM Swap
Installing your replacement 1998-1999 Suburban 1500 PCM is a job most DIYers can handle in under an hour with basic hand tools. Just follow these steps carefully.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post.
- Locate the PCM: On most of these trucks and vans, the PCM is located in the engine compartment, typically on the driver’s side inner fender or near the battery.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors. These older connectors can be brittle, so be gentle. Note their color and position.
- Remove the Old Module: Unbolt the PCM from its mounting bracket. It’s usually held in by a few 10mm bolts.
- Install the New Module: Mount your replacement PCM and securely tighten the bolts. Reconnect the wiring harnesses, making sure they click firmly into place.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Perform Security Relearn: You MUST perform the GM Passlock/VATS security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Your vehicle will not start until this is completed.
Verified Vehicle Compatibility List
This module, identified by service number 9355699, is a direct replacement for a wide range of GM vehicles. Please match your part number to ensure compatibility. This part is interchangeable with the following numbers: 09355699, 16266645, 16250279, 16258815, 09366810, 9366810.
CHEVROLET 2500 PICKUP 98-99 (Gasoline, LH Engine Compartment)
CHEVROLET 3500 PICKUP 98-99 (Gasoline, LH Engine Compartment)
SUBURBAN 1500/2500 98-99 (Gasoline, LH Front Engine Compartment)
TAHOE 98-99 (Gasoline, LH Front Engine Compartment)
ESCALADE 99 (LH Front Engine Compartment)
GMC 1500/2500/3500 PICKUP 98-99 (Gasoline, LH Engine Compartment)
YUKON 98-99 (LH Engine Compartment)
EXPRESS VAN 1500/2500/3500 98-99 (Gasoline)
SAVANA VAN 1500/2500/3500 98-99 (Gasoline)
ASTRO / SAFARI 98 (LH Front by Battery)
BLAZER S10/JIMMY S15 98 (RH Front Engine Compartment, w/o opt ZN4)
BRAVADA 98 (w/o build date opt ZN4)
ENVOY 98 (RH Front Engine Compartment, w/o opt ZN4)
ISUZU HOMBRE 98 (4.3L, w/o opt ZN4)
S10/S15/SONOMA 98 (4.3L, w/o opt ZN4)
Frequently Asked Questions
Do I really need to provide my VIN?
Yes, absolutely. Providing your 17-digit Vehicle Identification Number (VIN) is critical. We use it to load the exact, correct GM software for your truck’s specific engine, transmission, and options. This ensures perfect compatibility and performance.
Is any additional programming required after I install it?
No. The main engine and transmission programming is completed by us before shipping. The only procedure you must perform is the security relearn (also known as VATS or Passlock relearn), which syncs the module to your key’s anti-theft signal. This requires no special tools.
Is this a new part?
No, this is a high-quality, tested used OEM part that has been sourced from a salvaged vehicle. This allows us to provide a reliable, factory-spec component at a significant cost saving compared to a new unit from a dealer.
What if my original part number is different?
This module (9355699) replaces several different part numbers, including 16266645, 16250279, and others listed in the description. As long as your vehicle is on the compatibility list and your original module is one of the interchangeable numbers, this part will work perfectly once programmed to your VIN.
What tools do I need for the installation?
You’ll only need basic hand tools. Typically, a socket wrench with a 10mm socket to remove the mounting bolts and a tool to disconnect the battery terminal (often 8mm or 10mm) is all that’s required for the physical swap.