Restore Your Truck’s Brain with a Reliable, Programmed PCM
Is your 1998 Chevy S10 Blazer, GMC S15 Jimmy, or another classic GM truck giving you headaches? If you’re dealing with frustrating issues like a no-start condition, erratic engine behavior, stalling, or a persistent check engine light that won’t go away, the problem often points directly to a failing Powertrain Control Module (PCM). As a technician with over two decades of experience, I’ve seen how a faulty PCM can mimic a dozen other problems, leading to wasted time and money on unnecessary parts. This isn’t just a component; it’s the central command center for your engine and transmission, and when it fails, your vehicle’s reliability is gone.
We offer a straightforward, dependable solution. This is a tested, used OEM PCM that we program specifically for your vehicle using your VIN. We install the latest GM factory software updates, which often correct drivability issues and bugs that were present in the original programming. This means you get a component that’s not only a direct replacement but also functions optimally, restoring the performance and fuel economy you expect from your truck. Forget expensive dealership visits for programming—this module arrives at your door ready to install.
Case Study: A Tricky Diagnosis
A customer brought in his ’98 GMC Jimmy 4.3L that would crank but not start. He had already replaced the fuel pump, ignition coil, and crank sensor based on advice from forums. His scanner showed no communication with the PCM. After confirming the PCM had power and ground, it was clear the module itself was internally fried—a common failure I’ve seen on hundreds of these GM platforms due to age and heat cycles. Instead of a costly new unit from the dealer, we installed one of our pre-programmed modules. After a quick security relearn procedure, the truck fired right up and ran smoother than it had in years. This is the kind of simple, effective fix that gets you back on the road without breaking the bank.
Is Your Truck Exhibiting These PCM Failure Symptoms?
A failing computer can cause a wide range of issues. If you’re experiencing any of the following, a faulty PCM is a likely culprit:
- ✔ Check Engine Light is on with communication error codes (like U0100) or internal module failure codes (P0601, P0605).
- ✔ Engine cranks but will not start.
- ✔ Rough or unpredictable idling and stalling.
- ✔ A noticeable drop in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ The vehicle fails an emissions test.
- ✔ No signal to fuel injectors or ignition coils.
A Straightforward Guide to Installation
Installing your programmed 1998 Blazer S10 PCM is a job most DIYers can handle in under an hour with basic tools. This module is typically located in the engine bay for easy access.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most S10/Jimmy/Blazer models, the PCM is located in the engine compartment, often on the passenger (RH) side near the firewall or fender. On vans, it may be in the rear engine compartment.
- Disconnect the Old Module: Carefully unplug the electrical harness connectors. They have locking tabs that need to be released. Once unplugged, unbolt the module from its mounting bracket.
- Install the New PCM: Bolt the new, programmed module into place and securely reconnect the wiring harnesses. Ensure they click into place.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Perform Security Relearn (If Needed): In some cases, a simple security relearn procedure is required. Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this 2-3 times. The vehicle should then start and run normally.
Verified Vehicle Compatibility
This module is a direct replacement for service number 9366810 and interchanges with part numbers 09355699, 16266645, 16250279, and 16258815. It is guaranteed to fit the following vehicles with matching options:
- 1998 Oldsmobile Bravada (4.3L)
- 1998 GMC Envoy (4.3L)
- 1998 Isuzu Hombre (4.3L)
- 1998 Chevrolet S10 / GMC Sonoma (4.3L)
- 1998 Chevrolet Blazer S10 / GMC Jimmy S15 (4.3L)
- 1998-1999 Cadillac Escalade
- 1998-1999 Chevrolet/GMC C/K 1500, 2500, 3500 Pickups (Gasoline)
- 1998-1999 Chevrolet Suburban / GMC Yukon (Gasoline)
- 1998-1999 Chevrolet Tahoe (Gasoline)
- 1998-1999 Chevrolet Express / GMC Savana 1500, 2500, 3500 Vans (Gasoline)
- 1998 Chevrolet Astro / GMC Safari
Crucial: This compatibility is based on matching the service ID number from your original module. Please verify your part number before ordering. If you need help, just send us a message with your VIN.
Do I need to do any programming myself?
Do I need to do any programming myself?
No. We handle all the programming for you before we ship the part. We use your vehicle’s VIN to load the correct, updated GM software, making it a true plug-and-play installation for you.
What do you need from me after I order?
After you complete your purchase, you will need to send us your 17-digit Vehicle Identification Number (VIN). We cannot program and ship your module without it. You can typically find your VIN on your dashboard (visible through the windshield) or on the driver’s side door jamb sticker.
Is this a new part?
This is a high-quality, tested used OEM part sourced from a salvaged vehicle. We inspect and verify each unit before programming it to ensure reliability, offering you a cost-effective alternative to a brand new, expensive dealer part.
What’s the difference between a PCM and an ECM?
The terms are often used interchangeably. ECM (Engine Control Module) typically just controls engine functions. A PCM (Powertrain Control Module) is more common in modern vehicles and controls both the engine and the automatic transmission. For your 1998 Blazer S10 PCM, it manages the entire powertrain.
Will this fix my specific problem?
If your vehicle’s issues are caused by a faulty computer, this part is the correct solution. We recommend proper diagnosis to confirm the PCM is the point of failure. Check for consistent power and ground at the PCM connectors and scan for communication codes to be certain.