If you’re dealing with frustrating, hard-to-diagnose issues on your GM truck or van, your Powertrain Control Module (PCM) is a likely culprit. As the central computer for your engine and transmission, a failing PCM can cause everything from a no-start condition to poor fuel economy. This isn’t just an inconvenience; for a workhorse like a Savana or Express van, it means downtime and lost money. This replacement module, part number 16263494, is the reliable solution to get your vehicle back on the road and running as it should.
The biggest hurdle with replacing a PCM has always been the expensive and time-consuming programming required at a dealership. We eliminate that step entirely. Before this module ships, we flash it with the latest official GM software updates, specifically programmed to your vehicle’s unique VIN. This ensures perfect communication with all other onboard systems and often corrects factory drivability issues you may not have even known were software-related. You get a component that is truly ready for installation right out of the box.
Case Study: A Tricky Diagnosis
I remember a 2001 Express 2500 that came into my shop. The owner, a plumber, was at his wit’s end. The van would randomly stall at stoplights, but only when warm. No consistent codes, just an occasional P0300 (Random Misfire). We checked fuel pressure, ignition components, and sensors—all were fine. On a hunch, I monitored the PCM’s data stream and noticed the injector pulse width would erratically drop out just before a stall. We swapped in a VIN-programmed PCM, and the problem vanished instantly. The original unit had a heat-related internal failure that no scan tool could definitively pinpoint. It’s a classic example of how a faulty PCM can mimic other problems, and why a quality replacement is key.
Is Your GM Vehicle Showing These Symptoms?
A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, this module is your likely solution:
- ✔ Unexplained Check Engine Light (CEL) illumination
- ✔ Stalling, stumbling, or rough idling
- ✔ No-start or difficult starting conditions
- ✔ Noticeable decrease in fuel efficiency
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Diagnostic Trouble Codes (DTCs) such as P0601, P0605, or other communication errors.
Your Straightforward Installation Guide
Installing your new 1999-2002 Savana PCM is a job most DIYers can handle in under an hour. Follow these general steps for a successful replacement.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent electrical damage.
- Locate the PCM: On most Savana/Express vans, the module is in the LH rear of the engine compartment. On trucks and SUVs, it’s typically on the LH side, sometimes under the battery tray. Consult a repair manual for your specific model if unsure.
- Disconnect Connectors: Carefully unclip the wiring harness connectors from the old PCM. These connectors have locking tabs; do not force them. Inspect the terminals for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM in the same location and securely re-fasten it.
- Reconnect and Secure: Firmly plug the wiring harness connectors into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: Your vehicle may require a simple security relearn procedure to recognize the new PCM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes. A CASE (Crankshaft Angle Sensor Error) relearn may also be necessary with a capable scan tool for optimal performance.
Verified Compatibility for Your Vehicle
This module is a direct replacement for part number 16263494 and is also compatible with part numbers 16265035, 8162634940, 218-11787, and 21811787. It fits a wide range of GM vehicles. Please verify your model and year from the list below.
Frequently Asked Questions
Frequently Asked Questions
Do I need to do anything after I purchase?
Yes. After you place your order, you must provide us with your vehicle’s 17-digit VIN. We cannot program and ship your module without it. This ensures the software is a perfect match for your vehicle’s options.
Is this module difficult to install?
Not at all. It’s a direct-fit replacement. The physical swap is simple, requiring basic hand tools. The only additional step may be a security relearn procedure, which does not require special tools.
What does ‘VIN Programmed’ actually mean?
It means we load the module with the specific software calibration file from GM that corresponds to your vehicle’s VIN. This accounts for engine size, transmission type, axle ratio, and other factory options, ensuring seamless operation.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the PCM (like with codes P0601 or P0605), then yes, this part will resolve the issue. It’s crucial to properly diagnose the root cause before ordering.
Is a CASE relearn required?
For best performance and to prevent a potential P1336 trouble code, a CASE (Crankshaft Angle Sensor Error) relearn is recommended after installation. This procedure requires a bi-directional scan tool and synchronizes the new PCM with the crankshaft position sensor.