Is Your 1997 GM Truck or Van Running Rough?
If you’re behind the wheel of a classic ’97 GM workhorse like an Express 3500, a Chevy C/K pickup, or a GMC Suburban, you know they’re built to last. But when the brain of the operation—the Powertrain Control Module (PCM)—starts to fail, it can cause a host of confusing and frustrating problems. Over my 20+ years in the shop, I’ve seen these exact symptoms hundreds of times on this platform. The engine might crank but not start, idle erratically, or stall for no reason. You might also be dealing with a persistent Check Engine Light that no amount of parts-swapping seems to fix.
These issues often trace back to the original PCM. After decades of heat cycles under the hood and countless electrical signals, internal components like capacitors and driver circuits simply wear out. This isn’t a sign of a bad vehicle; it’s just the reality of aging electronics.
The Technician’s Perspective: Diagnosing a Failing PCM
When a ’97 GM truck or van comes into my bay with drivability issues, a failing PCM is high on my list of suspects. The symptoms are often a dead giveaway. Here’s what you might be experiencing:
- ✔ No-start or hard-starting conditions, especially when warm.
- ✔ Rough, stumbling idle that makes the whole vehicle shake.
- ✔ Poor acceleration or a feeling of low power.
- ✔ Abysmal fuel economy that seems to have dropped off suddenly.
- ✔ A Check Engine Light with codes related to internal module failure, communication errors, or multiple random sensor faults.
- ✔ Harsh or incorrect automatic transmission shifting.
The PCM is responsible for everything from fuel injector timing and spark delivery to transmission shift points. When it fails, it can send incorrect signals or no signals at all, leading directly to the problems listed above.
Expert Pro Tip
Before condemning your PCM, always perform the basics. Check your battery connections for tightness and corrosion, and verify the main engine grounds are clean and secure. On these ’97 GM vehicles, the PCM is often located in the engine bay on the driver’s side fender or near the battery. A poor ground connection can mimic PCM failure. I’ve saved customers hundreds of dollars by simply cleaning a ground strap. If the grounds are good and the symptoms persist, the PCM is the most likely culprit.
The Solution: A Direct-Fit, Programmed PCM
This isn’t just a replacement part; it’s a complete solution. This Powertrain Control Module, compatible with part numbers 16229684 and 8162296840, is the definitive fix for your vehicle’s electronic woes. The most critical part of the process is that we program it specifically for YOUR vehicle before it ever leaves our facility.
Here’s how it works: After your purchase, you simply provide us with your vehicle’s 17-digit VIN. We use that information to flash the module with the latest, most stable software updates directly from General Motors. This ensures the PCM is perfectly matched to your engine, transmission, and specific options. This crucial step means you get a module that is truly plug-and-play, eliminating the need for an expensive trip to a dealership for programming.
Guaranteed Compatibility for Your Vehicle
This module is the correct fit for a wide range of 1997 gasoline-powered GM and Isuzu models. Please verify your vehicle is on this list:
- ✔ Chevrolet Trucks: 1500, 2500, 3500 Pickup
- ✔ GMC Trucks: 1500, 2500, 3500 Pickup, S10/S15/Sonoma (4.3L V6)
- ✔ Chevrolet Vans: Express 1500, 2500, 3500 Van, Astro Van
- ✔ GMC Vans: Savana 1500, 2500, 3500 Van, Safari Van
- ✔ Chevrolet SUVs: Suburban 1500/2500, Tahoe, Blazer S10 (4.3L V6)
- ✔ GMC SUVs: Suburban 1500/2500, Yukon, Jimmy S15 (4.3L V6)
- ✔ Oldsmobile SUVs: Bravada (4.3L V6)
- ✔ Isuzu Trucks: Hombre (4.3L V6)
Installation is straightforward for anyone with basic mechanical skills. Simply disconnect the negative battery terminal, locate your old PCM, carefully unplug the wiring harnesses, and swap in the new one. Reconnect everything, and you’re ready to start your engine and enjoy smooth, reliable performance once again.