Is Your 2004 GM Truck or SUV Running Rough?
If you’re experiencing frustrating issues like a persistent check engine light, poor engine performance, stalling, or even a no-start condition in your 2004 GMC Sierra Denali, Chevrolet Silverado, Tahoe, or other compatible GM vehicle, a failing Powertrain Control Module (PCM) could be the culprit. The PCM, often called the ECM or engine computer, is the brain of your vehicle’s engine management system. When it fails, it can cause a wide range of problems that can be difficult to diagnose. Don’t let a faulty computer keep you off the road. This is your direct, reliable solution.
The Plug-and-Play Solution for Your Vehicle
This listing is for a replacement Engine Control Module, service number 12586242, which is a direct replacement for part numbers 19299226, 89017738, and many others. The best part? We handle the programming for you. Simply provide your vehicle’s VIN (Vehicle Identification Number) during checkout, and our technicians will flash the module with the latest, most up-to-date software directly from GM. This ensures perfect compatibility and optimal performance, eliminating the need for an expensive trip to the dealership. Your new computer will arrive at your door ready for installation.
From the Diagnostic Bay
We had a 2004 Yukon Denali come in with a classic case of “parts cannon” diagnostics. The owner had replaced the throttle body, MAF sensor, and all eight spark plugs trying to chase down an intermittent stalling issue and rough idle. No codes were stored consistently. After checking all the wiring and confirming the new parts were working, we hooked up our scope to the PCM’s driver circuits. We found erratic signals controlling the fuel injectors, but only when the engine was warm. The thermal stress was causing a hairline fracture on the PCM’s internal board. A new, properly programmed 2004 Sierra Denali ECM like this one solved the problem instantly. It’s a reminder that sometimes the issue lies with the component controlling everything else.
Common Symptoms of a Failing ECM
- ✔ Persistent Check Engine Light (CEL)
- ✔ Engine stalling, stuttering, or misfiring
- ✔ Drastic decrease in fuel economy
- ✔ Vehicle won’t start or is hard to start
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Loss of power and acceleration
- ✔ Inability to communicate with the module using a scan tool
Guaranteed Fitment and Compatibility
This engine computer is compatible with a wide range of 2004 General Motors trucks and SUVs equipped with 5.3L and 6.0L gasoline engines. It directly replaces service numbers 12586242, 19299226, 89017738, YFKD, YFKF, YFKH, YFKJ, YFKX, YFXL, YFXM, YFXN, YFXP, and YHTN. It is a guaranteed fit for models such as the Chevrolet Silverado, Suburban, Avalanche, Tahoe, SSR, Trailblazer EXT; the GMC Sierra, Yukon; the Cadillac Escalade; the Hummer H2; the Buick Rainier; and the Isuzu Ascender. Please verify your original part number matches one of the numbers listed to ensure correct fitment for your specific application.
Installation is straightforward for any DIY mechanic or professional technician. Once installed, you may need to perform a security relearn procedure and a Crankshaft Variation (CASE) relearn, which can be done with a capable bi-directional scan tool. This ensures the new computer communicates properly with your vehicle’s anti-theft system and crankshaft position sensor for smooth operation.
Frequently Asked Questions
Do I need to program this 2004 Sierra Denali ECM?
No. We program the module for you before it ships. All you need to do is provide us with your vehicle’s 17-digit VIN when you place your order. It will arrive ready to install.
What is a CASE relearn and will I need to do one?
A CASE (Crankshaft Angle Sensor Error) relearn is a procedure that calibrates the new computer to your engine’s crankshaft position sensor. This is required on most installations to prevent a P1336 trouble code and ensure accurate misfire detection. This procedure must be performed with a compatible high-level scan tool after the module is installed.
Where can I find my vehicle’s VIN?
Your VIN can be found on a metal plate on the driver’s side dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Is this a direct replacement for my original part?
Yes, this module is a direct replacement for any of the service numbers listed in the description, including 12586242, 19299226, and 89017738. As long as your original module carries one of these numbers, this part will work for your vehicle.
What if I have problems after installation?
While our VIN programming ensures compatibility, installation issues can sometimes arise. Please contact our expert customer support team. We can help diagnose common issues like a needed security relearn or confirm that all connections are secure.