Restore Peak Performance to Your GM Truck
Is your dependable 1998-1999 Chevy or GMC truck suddenly plagued by frustrating issues like a persistent check engine light, erratic shifting, or a no-start condition? Before you spend a fortune on diagnostics or a trip to the dealership, the root cause is often a failing Powertrain Control Module (PCM). As the electronic brain of your vehicle, a faulty PCM can create a cascade of problems that are difficult to pin down. This replacement module is the reliable, straightforward solution to get your truck running like it should.
With over 20 years of experience under the hood, I’ve seen firsthand how a failing computer can mimic a dozen other mechanical problems. This isn’t just a part; it’s a solution that restores communication between your engine and transmission. We take the guesswork out of the repair by pre-programming this 1998-1999 Chevrolet 1500 PCM with the latest GM software updates, specifically matched to your vehicle’s VIN. This ensures all factory parameters for your engine, transmission, and emissions equipment are loaded and ready to go.
A Technician’s Notebook
I remember a ’99 GMC Yukon that came into the shop with a complaint of intermittent stalling at stoplights. The owner had already replaced the fuel filter and spark plugs with no luck. There were no active trouble codes, making it a real head-scratcher. After confirming fuel pressure and ignition spark were solid, my attention turned to the PCM. With the engine idling, a simple tap test on the PCM housing caused the engine to stumble and die immediately. This confirmed an internal failure. We installed a VIN-programmed module just like this one, and the customer called back a week later to say his Yukon had never run better. It’s often the simple, core component that restores reliability.
Common Signs of a Failing PCM
- âś” Check Engine Light is on with internal processor codes like P0601, P0604, or P0606.
- âś” Your vehicle fails to start or stalls intermittently for no apparent reason.
- âś” The transmission shifts harshly, late, or erratically.
- âś” You experience a sudden, unexplained drop in fuel economy.
- ✔ Communication issues with your scan tool, showing a “No Communication” error.
- âś” Poor engine performance, including rough idling, hesitation, or misfiring.
A Straightforward Guide to Installation
Installing your replacement 1998-1999 Chevrolet 1500 PCM is a job most DIYers can handle in their own driveway. Follow these steps for a successful installation.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before beginning any electronic work.
- Locate the Module: On most of these trucks and SUVs, the PCM is located in the engine compartment, typically on the driver’s side inner fender or near the battery.
- Disconnect the Connectors: Carefully unlatch and remove the wiring harness connectors from the old module. Inspect them for any corrosion or damage.
- Remove the Old PCM: Unbolt the old module from its mounting bracket.
- Install the New PCM: Mount the new, pre-programmed module in place and securely fasten it.
- Reconnect Everything: Plug the wiring harnesses back into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Relearn Procedure: In many cases, you may need to perform a simple security relearn procedure (often called Passlock or VATS relearn) to allow the vehicle to start. This procedure can be found online and typically involves turning the key to the ‘ON’ position for 10-15 minutes. A Crankshaft Variation (CASE) relearn may also be required with a capable scan tool to eliminate a P1336 code, though the truck will run without it.
Will This Fit My Vehicle?
This module is a direct replacement for part numbers 09366810, 16250279, and 09355699. It is guaranteed to fit the following models with the specified options. Please verify your vehicle’s ID number matches before ordering.
ASTRO 98-99 (4.3L, ID 16250279)
BLAZER S10 98 (w/o build date opt ZN4; ID 16250279 or 16258815)
CHEVROLET 1500 PICKUP 98-99 (Gasoline, 5.0L/5.7L, ID 16250279)
CHEVROLET 2500 PICKUP 98-99 (Gasoline, ID 16250279)
CHEVROLET 3500 PICKUP 98-99 (Gasoline, ID 16250279)
EXPRESS 1500/2500/3500 VAN 98 (Gasoline, ID 16250279)
S10 PICKUP 98 (4.3L, w/o build date opt ZN4; ID 16250279 or 16258815)
SUBURBAN 1500/2500 98-99 (Gasoline, ID 16250279)
TAHOE 98-99 (Gasoline, ID 16250279)
GMC Models:
ENVOY 98 (w/o build date opt ZN4; ID 16250279 or 16258815)
GMC 1500 PICKUP 98-99 (Gasoline, 5.0L/5.7L, ID 16250279)
GMC 2500 PICKUP 98-99 (Gasoline, ID 16250279)
GMC 3500 PICKUP 98-99 (Gasoline, ID 16250279)
JIMMY S15 98 (w/o build date opt ZN4; ID 16250279 or 16258815)
SAFARI 98-99 (ID 16250279)
SAVANA 1500/2500/3500 VAN 98 (Gasoline, ID 16250279)
SONOMA 98 (4.3L, w/o build date opt ZN4; ID 16250279 or 16258815)
YUKON 98-99 (ID 16250279)
Other GM Models:
BRAVADA 98 (4.3L, w/o build date opt ZN4; ID 16250279 or 16258815)
CADILLAC ESCALADE 99 (ID 16250279)
ISUZU HOMBRE 98 (4.3L, w/o extended build date opt ZN4; ID 16250279 or 16258815)
Frequently Asked Questions
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to access the correct GM factory calibration file for your specific truck. This ensures the 1998-1999 Chevrolet 1500 PCM is programmed for your engine, transmission, tire size, and other options for perfect compatibility.
Is this part difficult to install?
No, this is a direct-fit part. The physical installation is simple for anyone with basic tools. The only extra step may be a security relearn procedure, which does not require any special equipment.
Do I need to have this programmed at a dealer?
No. The main benefit of our service is that the module arrives at your door already programmed and ready for installation. This saves you the time, cost, and hassle of a dealership visit.
What part numbers does this module replace?
This module is a direct replacement for service numbers 09366810, 16250279, and 09355699. Please check the sticker on your current module to confirm.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the PCM (common codes P0600-P0606), then yes, this part will resolve the issue. It is always best to have the codes read to properly diagnose the problem before ordering.