Restore Peak Performance to Your GM Vehicle
Is your 1998 Pontiac Bonneville, Grand Prix, or another trusted GM vehicle suddenly giving you trouble? If you’re dealing with a persistent check engine light, unexpected stalling, poor fuel mileage, or erratic transmission behavior, the culprit is often a failing Powertrain Control Module (PCM). As the central computer for your engine and transmission, its health is critical to your car’s operation. This replacement PCM, part number 16236757, is the reliable, straightforward solution you need to get back on the road with confidence.
The biggest challenge with PCM replacement has always been the programming. Historically, you’d have to buy the part and then pay for towing and expensive labor at a dealership to have it programmed. We eliminate that step entirely. Simply provide us with your vehicle’s VIN during checkout, and our technicians will program the module with the latest official GM software updates specific to your car. It arrives at your door ready for installation—a true plug-and-play fix.
Case Study: A Tricky Diagnosis
I remember a 1998 Buick LeSabre that came into the shop with a maddeningly intermittent stalling issue. The owner had already replaced the crank sensor and fuel filter at another garage, but the problem persisted. After hooking up my scan tool, I noticed that communication with the PCM would drop out just before the engine quit. After ruling out wiring issues, I suspected an internal PCM failure, likely a cold solder joint that would separate as the engine bay heated up. We installed one of our VIN-programmed PCMs, and the problem was solved on the first test drive. The customer was thrilled to have a reliable car again without wasting more money on guesswork.
Common Signs of a Failing PCM
If the brain of your engine is failing, your vehicle will let you know. Watch out for these common symptoms that point to a faulty 1998 Bonneville PCM or related module:
- âś” Persistent Check Engine Light that won’t clear
- âś” Stored diagnostic trouble codes (DTCs) for internal module failure, such as P0601, P0602, or P0606
- âś” The engine cranks but refuses to start
- âś” Unexplained stalling, especially after the vehicle has warmed up
- âś” Noticeable drop in fuel efficiency
- âś” Harsh, delayed, or erratic automatic transmission shifting
- âś” Inability for a scan tool to communicate with the PCM
A Straightforward Guide to Installation
You don’t need to be a master mechanic to install this part. With basic hand tools, you can have your vehicle running right in under an hour.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the Module: On most of these GM models, the PCM is housed within the air cleaner assembly in the engine bay. This protects it from the elements.
- Disconnect Harnesses: Carefully unclip and unplug the main electrical connectors from the old PCM. Take note of their position.
- Remove the Old PCM: Unbolt the module from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Secure your new, pre-programmed module onto the mounting bracket. Firmly reconnect the wiring harnesses, ensuring they click into place.
- Final Steps: Reinstall the air cleaner assembly and reconnect the negative battery terminal. In some cases, a simple security relearn procedure (VATS/Passlock) may be necessary, which typically involves turning the key to the ‘ON’ position for 10-15 minutes and can be done without special tools.
Verified Vehicle Compatibility
This module is a direct replacement for a wide range of GM vehicles. Please verify your part number (16236757) or one of the compatible service numbers (09356741, 9356741, 9357034, 9357440, 9366314) for a guaranteed fit.
Frequently Asked Questions
Frequently Asked Questions
How do I provide my VIN for programming?
After you complete your purchase, you will receive instructions to reply with your 17-digit Vehicle Identification Number (VIN). We cannot ship your part until we receive this information.
Is this module really plug-and-play?
Yes. Because we program it to your VIN before shipping, it is ready for installation right out of the box. No trip to the dealer is required. A simple security relearn may be needed, which you can do yourself.
What if my original part number is not 16236757?
This unit is also a direct replacement for several other service numbers, including 09356741, 9357034, 9357440, and 9366314. As long as your part number is on our compatibility list, this module will work for you.
Will this fix my car’s problem for sure?
This part corrects issues caused by a faulty PCM. While the symptoms listed are very common for PCM failure, we always recommend a proper diagnosis by a qualified mechanic to confirm the PCM is the root cause of your problems before ordering.
Do I need to send my old part back?
No core charge is required for this part. You can keep or recycle your old module.