Restore Your Van’s Performance and Reliability
Is your 1998-1999 GMC Savana 1500 van running rough, stalling, or refusing to start? Are you staring at a persistent Check Engine Light, frustrated by poor fuel economy or failed emissions tests? A faulty Powertrain Control Module (PCM) is often the culprit behind these baffling issues. As the brain of your vehicle’s engine and transmission, when the PCM fails, it can cause a cascade of problems that leave you stranded. This isn’t just an inconvenience; it’s a hit to your productivity and peace of mind.
This is a reliable, tested, and pre-programmed replacement PCM, part number 09355699. We take the guesswork and high cost out of the repair. Forget expensive dealership visits for programming. Simply provide us with your vehicle’s VIN after purchase, and our technicians will flash this module with the latest GM software updates specific to your van. This ensures that when it arrives, it’s ready for a straightforward installation, restoring the precise fuel delivery, spark timing, and transmission shifting your vehicle had from the factory.
From the Diagnostic Bay: A Common Pitfall
I remember a 1999 Express van that came into my shop with classic ‘bad PCM’ symptoms—erratic shifting and a no-start condition after it warmed up. The owner had already replaced two sensors based on forum advice. Before condemning the computer, I always perform a voltage drop test on the main power and ground circuits to the PCM. On these GM vans and trucks, the ground connection on the engine block or frame can corrode, causing intermittent issues that perfectly mimic a failing module. After cleaning and securing the main ground, the van ran perfectly. While this PCM will solve a true internal failure, always check your grounds first—it’s a 10-minute check that can save you hundreds.
Is Your Van Showing These Red Flags?
A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, this module is the likely solution for your 1998-1999 Savana 1500 PCM issues:
- ✔ Check Engine Light is illuminated with codes like P0601 (Internal Memory Error) or P0606 (PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling or rough idling.
- ✔ Noticeable decrease in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to pass a state emissions inspection.
- ✔ Communication errors with diagnostic scan tools.
A Straightforward Guide to Installation
Installing your pre-programmed 1998-1999 Savana 1500 PCM is a manageable job for a DIYer. Follow these steps to get your vehicle back in service quickly.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most Savana and Express vans, the PCM is located in the engine compartment, typically on the driver’s side near the rear of the engine bay.
- Disconnect the Connectors: Carefully unplug the wiring harness connectors from the old PCM. These connectors have locking tabs that need to be released. Avoid pulling on the wires themselves.
- 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 the replacement PCM onto the bracket and securely reconnect the wiring harnesses. Ensure they click into place.
- Reconnect the Battery: Reattach the negative battery terminal.
- Perform Security Relearn (If Necessary): Your vehicle is equipped with a Passlock/VATS security system. You may need to perform a simple key-cycle relearn procedure. Turn the key to the ‘ON’ position (without starting) for 10-15 minutes, then turn it ‘OFF’ for 10 seconds. Repeat this two more times. On the fourth try, the vehicle should start.
Verified Fitment for Your GM Truck or Van
This module, identified by part number 09355699, is a direct replacement for a wide range of GM vehicles. Please match your original part number or verify your vehicle is on this list. This unit is compatible with part numbers 09355699, 16266645, 16250279, 16258815, and 09366810.
– 1500/2500/3500 Pickup (98-99)
– Astro Van (98)
– Blazer S10 (98)
– Express 1500/2500/3500 Van (98-99)
– S10 Pickup (98)
– Suburban 1500/2500 (98-99)
– Tahoe (98-99)
GMC:
– 1500/2500/3500 Pickup (98-99)
– Envoy (98)
– Jimmy S15 (98)
– Safari Van (98)
– Savana 1500/2500/3500 Van (98-99)
– Sonoma (98)
– Yukon (98-99)
Cadillac:
– Escalade (99)
Oldsmobile:
– Bravada (98)
Isuzu:
– Hombre (98)
Frequently Asked Questions
Do I really need to provide my VIN?
Yes, providing your Vehicle Identification Number (VIN) is essential. We use it to load the correct, vehicle-specific GM software and calibrations onto the PCM. This step ensures proper engine, transmission, and emissions system operation and makes the installation process plug-and-play.
Is this a new part?
No, this is a high-quality, tested used OEM (Original Equipment Manufacturer) part sourced from a salvaged vehicle. This provides OEM reliability and a perfect fit at a fraction of the cost of a new unit from a dealer.
Will this fix my ‘No Communication’ issue?
In many cases, yes. If your scan tool cannot communicate with the engine computer, it often points to an internal failure of the PCM itself. This replacement module is a direct solution for that problem.
What is the security relearn procedure?
It’s a simple process to sync the new PCM with your vehicle’s anti-theft system (VATS/Passlock). After installation, you’ll typically cycle the key from ‘ON’ to ‘OFF’ a few times in 10-minute intervals. Detailed instructions are included above, and it requires no special tools.
Are any other steps required after installation?
In some specific cases, a Crankshaft Position System Variation (CASE) relearn may be needed to clear a P1336 code. This procedure requires a capable bidirectional scan tool and is often performed by a professional mechanic to optimize engine timing. However, the vehicle will run and drive without it.