Restore Your Truck’s Brain and Drivability
Is your Isuzu Hombre or GM truck acting up? Experiencing frustrating issues like a persistent Check Engine Light, erratic shifting, stalling, or poor fuel mileage? The Powertrain Control Module (PCM) is the central computer of your vehicle, managing everything from fuel injection to transmission shift points. When it starts to fail, it can cause a wide range of problems that are often misdiagnosed. This module, part number 8162634940, is the direct, reliable solution to get your truck running like it should.
As a technician with over two decades of experience, I’ve seen countless hours and dollars wasted on replacing sensors and parts when the PCM was the root cause all along. This isn’t just a replacement part; it’s a complete solution. We take the hassle out of the repair by programming the module specifically to your vehicle’s VIN before we ship it. This ensures it has the latest GM software updates and is ready for installation right out of the box, saving you a costly trip to the dealership for programming.
Case Study: The Ghost in the Machine
A customer brought in a ’99 GMC Jimmy with the 4.3L, a sibling to the Isuzu Hombre. The complaint was intermittent stalling and a harsh 1-2 shift. They had already replaced the throttle position sensor and the mass airflow sensor with no luck. A quick scan showed no specific sensor codes, but a pending P0601 (Internal Control Module Memory Check Sum Error). This code is a dead giveaway. After confirming power and grounds to the PCM were solid, we swapped in a pre-programmed module just like this one. The shifting smoothed out immediately, the stalling disappeared, and the customer was back on the road in under an hour. It’s a classic example of how a failing PCM can mimic other component failures.
Is Your Truck Showing These Signs of PCM Failure?
A faulty PCM can manifest in many ways. If you’re experiencing any of the following, this module is likely the fix you need:
- âś” Check Engine Light is on with codes like P0601, P0604, or P0606
- âś” Engine cranks but refuses to start
- âś” Random stalling or rough idling
- âś” Noticeable decrease in fuel economy
- âś” Harsh or erratic automatic transmission shifting
- âś” Failure to pass an emissions test
- âś” Communication errors with scan tools
A Straightforward Guide to Installation
Installing your new PCM is a job most DIYers can handle with basic tools. Just follow these steps carefully.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 10 minutes to allow the system to fully discharge.
- Locate the PCM: On the 1998-2000 Isuzu Hombre (and its S-10/Sonoma cousins), the PCM is typically located in the engine bay on the right-hand (passenger) side, near the firewall or inner fender.
- Disconnect the Connectors: Carefully unclip and remove the electrical wiring harnesses from the old module. These connectors have locking tabs that must be released before pulling. Avoid forcing them.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware as you may need it for the new module.
- Install the New PCM: Mount your new, pre-programmed module in place and secure it with the original hardware.
- Reconnect Everything: Firmly plug the wiring harnesses back into the new PCM until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn (If Needed): In many cases, you will need to perform a simple security relearn procedure. Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this cycle 3 times. The vehicle should then start and run normally.
Verified Vehicle Compatibility
This module is a direct fit for a wide range of GM trucks and vans. Please verify your vehicle is on this list and that the part number matches. This module is compatible with part numbers: 16263494, 16265035, 8162634940, 218-11787, 21811787.
ASTRO 99-01 Electronic Control Module; (LH front by battery), ID 16263494
BLAZER S10/JIMMY S15 98-00 Electronic Control Module; (RH front engine compartment)
BRAVADA 98-00 Electronic Control Module; (6-262, 4.3L)
ENVOY 98-00 Electronic Control Module; (RH front engine compartment)
S10/S15/SONOMA 98-00 Electronic Control Module; 4.3L
CHEVROLET/GMC 1500/2500/3500 PICKUP 99-00 (Gasoline)
SIERRA/SILVERADO 1500 PICKUP 99-00 (6 cylinder)
EXPRESS/SAVANA 1500/2500/3500 VAN 99-02 (Gasoline)
TAHOE/YUKON 99-00 (Gasoline)
ESCALADE 99-00
SUBURBAN 1500/2500 99 (Gasoline)
SAFARI (GMC) 99-01 Electronic Control Module
Note: Some 1998 models require build date option ZN4. Please check your service parts sticker or contact us with your VIN to confirm.
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to program the module with the exact software and calibrations for your truck’s specific options, engine, and transmission. This ensures perfect compatibility and function without any additional programming required on your end.
Is this a simple plug-and-play part?
Yes! Because we program it to your VIN before shipping, the process is as close to plug-and-play as possible. In most cases, you will only need to perform a simple key-cycle security relearn procedure after installation, which requires no special tools.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls the transmission’s electronic solenoids and shift logic. If your PCM is faulty, it can cause harsh shifting, delayed engagement, or incorrect gear selection. This module can resolve those issues if the PCM is the cause.
What if my original part number is different?
This module replaces several part numbers, including 16263494, 16265035, and others. As long as your vehicle is on our compatibility list, this module will function correctly as a replacement, loaded with the proper software for your VIN.
Do I need to return my old PCM (core)?
No core return is required for this purchase. You can keep or dispose of your old module.