Mr. Rawles,
I recently have been going through the PCM/ECM/ECU vehicle engine/transmission control module nightmare. And it is a nightmare. Dealers typically won’t warrantee or allow return/refund on the vehicle computers unless they perform the diagnostics first. That’s a couple hundred bucks right there, before you get to buying the computer – which in my case for a 10 year old truck was $480, before sales tax. Then you have the labor to install it. Oh, and only the dealer can program it.
So I started snooping around on Google. Using the search terms “remanufactured PCM” and “remanufactured ECM” I found dozens of links to companies which sell preprogrammed vehicle computers [from wrecking yards] for all makes and models. And they are “plug and play”. Meaning that a reasonably able person could put one in themselves. And the prices seem to run about $150, rather than $500 or more. All the caveats posted by earlier contributors about multiple computers on a vehicle, and other factors, still apply. I only wanted to point out that there are other sources besides the dealers. And their return policies, warrantees, and delivery beat the pants off the dealers to boot! As always, caveat emptor – perform your own due diligence- YMMV. – The Homesick Idahoan (Still behind enemy lines)