Restore Your Vehicle’s Performance with a Reliable, Programmed PCM
Is your Chevrolet Astro, GMC Safari, or another GM truck from the late ’90s giving you headaches? If you’re dealing with a frustrating no-start condition, erratic engine behavior, stalling, or a persistent Check Engine Light, the culprit is often a failing Powertrain Control Module (PCM). As the central computer for your engine, a faulty PCM can cause a cascade of problems that leave you stranded. This isn’t just an inconvenience; it’s a critical component for your vehicle’s reliability and performance.
This is a dependable, tested OEM Engine Control Module, part number 16250279, recovered from a salvaged vehicle. We take the biggest hassle out of the repair process: programming. Before we ship this module to you, our technicians will flash it with the latest GM software updates, specifically matched to your vehicle using the VIN you provide. This means you get a part that is ready to install right out of the box, saving you a costly trip to the dealership and hours of diagnostic frustration. It’s the straightforward, effective solution to get your truck or van running smoothly again.
From the Diagnostic Bay: The Case of the Intermittent Stall
A customer brought in their ’99 Chevy Express van with a problem that had stumped two other shops: it would run perfectly for days, then suddenly stall at a stoplight and refuse to restart for an hour. There were no consistent trouble codes, just a history of cleared P0300 (Random Misfire) codes. After checking fuel pressure, spark, and sensor data, everything looked normal. However, from my experience with these GM platforms, I know the PCM can fail internally from heat and vibration, causing these ghost-like issues. We connected a lab scope to the injector control circuits and eventually caught the PCM dropping the signal during a hot soak. Swapping in a known-good, correctly programmed PCM like this one solved the problem instantly. It’s a reminder that sometimes the ‘brain’ itself is the issue, even without a clear trouble code pointing to it.
Is Your GM Vehicle Showing These Signs?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, this module is likely the solution you need. In my shop, these are the classic symptoms we see that point directly to a faulty computer.
- ✔ The engine will not start, but the battery and starter are good.
- ✔ Unexplained and random engine stalling, especially when warm.
- ✔ A noticeable drop in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ The Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error), P0605 (Internal Control Module ROM Error), or communication errors.
- ✔ Failure to pass an emissions test due to monitor readiness issues.
Your Straightforward Installation Guide
Installing your replacement 1998 Astro PCM is a manageable job for a confident DIYer. The key is taking your time and following the correct procedure. Our pre-programming service eliminates the most difficult step.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental power surges.
- Locate the PCM: On most of these vehicles (like the Astro, Safari, and S10/Blazer), the PCM is located in the engine compartment, often near the battery or on the fender well. In Express and Savana vans, it’s typically found in the LH rear engine compartment.
- Disconnect the Wiring: Carefully unplug the electrical connectors. These connectors have locking tabs that must be released before you can pull them off. Do not force them. Inspect the pins on both the harness and the old module for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware, as you may need to reuse it.
- Install the New Module: Mount your new, programmed PCM securely onto the bracket. Reconnect the wiring harnesses, ensuring they click firmly into place.
- Reconnect the Battery: Reattach the negative battery terminal.
- Perform Security Relearn (If Necessary): While our programming handles most of the work, some GM vehicles of this era require a simple security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. Your vehicle’s service manual will have the exact steps if required.
Verified Fitment For These GM Models
This module, identified by service number 9355699, is a direct replacement for a wide range of popular GM trucks and vans. Please verify your part number or match your vehicle from the list below. This is a crucial step to ensure compatibility for your specific 1998 Astro PCM or other model replacement.
- Astro Van: 1998
- Blazer S10 / Jimmy S15: 1998 (w/o build date opt ZN4)
- Bravada: 1998 (w/o build date opt ZN4)
- Cadillac Escalade: 1999
- Chevrolet / GMC 1500 Pickup: 1998-1999
- Chevrolet / GMC 2500 Pickup: 1998-1999 (Gasoline)
- Chevrolet / GMC 3500 Pickup: 1998-1999 (Gasoline)
- Envoy: 1998 (w/o build date opt ZN4)
- Express / Savana 1500 Van: 1998-1999
- Express / Savana 2500 Van: 1998-1999 (Gasoline)
- Express / Savana 3500 Van: 1998-1999 (Gasoline)
- Isuzu Hombre: 1998 (4.3L, w/o extended build date opt ZN4)
- S10 / S15 / Sonoma Pickup: 1998 (4.3L, w/o build date opt ZN4)
- Suburban 1500 / 2500: 1998-1999 (Gasoline)
- Tahoe / Yukon: 1998-1999 (Gasoline)
Compatible Part Numbers: 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, 9366810
Frequently Asked Questions
Frequently Asked Questions
Do I need to do any programming myself?
No. We handle all the programming before shipping. We will flash the module with the latest GM software updates using the VIN you provide at checkout. This makes the installation process much simpler for you.
Why do you need my VIN?
Your Vehicle Identification Number (VIN) contains critical information about your vehicle’s specific options, engine, transmission, and emissions equipment. Programming the PCM with your VIN ensures it works perfectly with your exact configuration.
Is a used PCM reliable?
Absolutely. This is a genuine OEM part that has been tested to ensure it is fully functional. OEM electronics are built to a high standard, and using a tested, salvaged part is a cost-effective and dependable way to repair your vehicle.
Will this fix my Check Engine Light?
If the Check Engine Light is caused by an internal failure of your old PCM (like code P0601), then yes, this part will resolve the issue. However, you should always ensure other potential causes, like faulty sensors or wiring, have been ruled out for a complete repair.
What tools do I need for installation?
For most applications, you will only need basic hand tools, such as a socket set and ratchet, to remove the mounting bolts and disconnect the battery. No special electronic tools are required.