* Online Auto Parts Retailers: Sites like eBay, Amazon, Car-Part.com, and RockAuto are good starting points. Car-Part.com is particularly useful for finding parts from junkyards. Be sure to specify the year, make, model, and engine (L67) to get the correct PCM. Check seller ratings carefully.
* Junkyards (Auto Recyclers): Local junkyards or salvage yards are often the cheapest option, but you'll need to call around and check their inventory. They may be able to test the PCM for you, which is highly recommended before purchasing a used unit.
* Forum Communities: Online forums dedicated to Pontiac Grand Prix or the L67 engine might have members who have a PCM for sale or can point you towards a reliable source. Searching forums for "L67 PCM replacement" or similar terms can be helpful.
* Specialty Parts Suppliers: Some businesses specialize in used or rebuilt PCMs. A quick online search for "rebuilt PCM [your car's details]" might turn up some options.
Important Considerations:
* Programming: Used PCMs *may* need to be programmed to your car's specific VIN. This often requires specialized tools and software, potentially costing extra. A remanufactured unit will frequently come pre-programmed to work with a wider range of vehicles. Check with the seller about programming requirements.
* Testing: Before buying a used PCM, get it tested if possible. A faulty unit will just waste your time and money.
* Warranty: If buying used, check for any warranty offered by the seller.
* Compatibility: Absolutely confirm the PCM's compatibility with your specific car and engine. Slight variations in the PCM can exist even within the same model year.
Finding a cheap *and* reliable used PCM requires patience and diligent research. Don't rush the process, and always prioritize getting a tested and compatible unit. Remember, a malfunctioning PCM can cause significant engine problems, so it's worth investing in a reliable option, even if it's slightly more expensive than a questionable used part.
