Is Your GM Truck or SUV Running Rough? The PCM Might Be the Culprit.
If your 1999 Cadillac Escalade, Chevy Tahoe, or GMC Yukon is suffering from inexplicable performance issues, a persistent Check Engine Light, or even a no-start condition, the problem may lie deep within its electronic nervous system: the Powertrain Control Module (PCM). This essential computer is the brain of your vehicle, managing everything from fuel injection and spark timing to transmission shifting and emissions controls. When it fails, it can cause a cascade of frustrating and difficult-to-diagnose symptoms.
This is a genuine, used OEM Powertrain Control Module, part number 16258815 (interchangeable with 09355699 and others listed below), that has been meticulously tested and is ready for installation. We take the guesswork and hassle out of the replacement process by programming the module specifically for your vehicle using the VIN you provide. This ensures that all factory settings and the latest GM software updates are loaded, making the installation process as seamless as possible.
From the Diagnostic Bay
We once had a 1999 Chevy Suburban in the shop that was driving its owner crazy. It would randomly stall at stoplights and had a rough, hunting idle. He had already replaced the spark plugs, wires, and even the fuel pump, but the problem persisted. After hooking up our diagnostic scanner, we saw erratic data from multiple sensors. An inexperienced technician might have started chasing those sensors, but the pattern suggested a central processing issue. We swapped in a known-good, programmed PCM, and the truck immediately purred like a kitten. The original PCM had failing internal circuits that were corrupting the data, proving that sometimes the problem isn’t the sensors, but the brain reading them. This is a classic failure mode for these older GM computers.
Common Symptoms of a Failing Powertrain Control Module
- ✔ Persistent and illuminated Check Engine Light (CEL)
- ✔ Engine stalling, stumbling, or misfiring
- ✔ Rough or erratic idling
- ✔ Poor fuel economy
- ✔ Harsh or incorrect automatic transmission shifting
- ✔ Failure to pass emissions tests
- ✔ Complete no-start condition where the engine cranks but won’t fire
- ✔ Communication errors with diagnostic scan tools
The Solution: A VIN-Programmed 1999 Escalade PCM
Don’t let a faulty computer keep your reliable GM truck off the road. This replacement module is a direct-fit, cost-effective solution to restore your vehicle’s performance and dependability. The most critical step in replacing a PCM is the programming, which we handle for you before shipping. By providing your vehicle’s 17-digit VIN during checkout, you ensure the module arrives with the correct software for your specific engine, transmission, and emissions equipment. This eliminates the need for an expensive trip to the dealership for programming.
This unit is sourced from a salvaged vehicle and has been inspected to ensure it is fully functional. It is a genuine OEM part, not an aftermarket clone, guaranteeing compatibility and adherence to GM’s original performance specifications. Installation is straightforward for a DIY mechanic or any professional technician. In most cases, a simple security relearn procedure may be required after installation, which can often be done without special tools.
Frequently Asked Questions
What exactly does the PCM do?
The Powertrain Control Module (PCM) is your vehicle’s main computer. It takes information from sensors all over the engine and transmission to control fuel delivery, ignition timing, emissions systems, and automatic transmission shift points to ensure optimal performance, efficiency, and low emissions.
Do I need to get this computer programmed?
No. We handle the programming for you before the part ships. You must provide us with your vehicle’s VIN at the time of purchase so we can load the correct GM software for your specific configuration.
Is this part difficult to install?
The physical installation is typically simple, involving disconnecting the battery and swapping the module. However, after installation, you may need to perform a security relearn procedure (often called a VATS relearn) to allow your vehicle to start. This procedure can usually be done without special tools and instructions are widely available online.
How can I be sure this fits my vehicle?
This module, identified by service number 09355699, fits a wide range of 1998-1999 GM trucks, vans, and SUVs. Please check the comprehensive fitment list on this page and verify that your vehicle and engine option are listed. Matching the part number from your old module is the best way to guarantee compatibility.
What information do you need from me?
After you complete your purchase, we will need your vehicle’s 17-digit Vehicle Identification Number (VIN). This is typically found on the driver’s side dashboard (visible through the windshield) or on the driver’s door jamb sticker.