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I would hope in your search for information you found that the modules have to be coded to each other, and some are coded to the VIN# and cannot be recoded to a new VIN# (the immobilizer in particular - what good would it be as an anti-theft device if plugging a different one in allowed the car to start.)
That would be my WAG - and that's all it is - a WAG. To replace something like an immobilizer - the mechanic is expected to extract information from the old module and then write it to a new module. As far as I know - once written to - an immobilizer can't be overwritten (meaning used ones are pretty much useless.) The keys also must be registered with the immobilizer.
When the immobilizer thinks the car has been stolen, it allows the starter to crank but doesn't turn on the ignition, which sounds like what you're experiencing.
Does the mechanic you're using have a PIWIS (the official Porsche diagnostics tool)? Without it - he'll be troubleshooting by replacing parts. Unfortunately, this has a low chance of success in this case and can become extraordinarily expensive. Having adequate diagnostics could well lead to a much quicker and less costly solution than the guesswork and grasping for straws the mechanic is now doing.
I would hope in your search for information you found that the modules have to be coded to each other, and some are coded to the VIN# and cannot be recoded to a new VIN# (the immobilizer in particular - what good would it be as an anti-theft device if plugging a different one in allowed the car to start.)
That would be my WAG - and that's all it is - a WAG. To replace something like an immobilizer - the mechanic is expected to extract information from the old module and then write it to a new module. As far as I know - once written to - an immobilizer can't be overwritten (meaning used ones are pretty much useless.) The keys also must be registered with the immobilizer.
When the immobilizer thinks the car has been stolen, it allows the starter to crank but doesn't turn on the ignition, which sounds like what you're experiencing.
Does the mechanic you're using have a PIWIS (the official Porsche diagnostics tool)? Without it - he'll be troubleshooting by replacing parts. Unfortunately, this has a low chance of success in this case and can become extraordinarily expensive. Having adequate diagnostics could well lead to a much quicker and less costly solution than the guesswork and grasping for straws the mechanic is now doing.
