If the damage to the diaphram is substantial enough, it could prevent the car from starting/running. Sometimes they have just a slight tear and the engine will still be able to run, though not quite correctly.

I have no idea where you might be able to find a kit to rebuild it, but it's a Bosch part that was also used on other Djet fitted cars... Audi, VW, Porsche, Mercedes... check with whoever you can find that sells parts for those, I suppose.

The other option would be to try to find a good used one - if you do this, you'll want to be sure that the part number matches what you currently have.

The diaphram is brass (I think.. it might be copper but I'm thinking it's brass); its job is to move based on how much vacuum exists within the intake manifold. This has a significant effect on the fuel supplied via the injectors. Unlike some of the other components in the Djet system, the engine just won't run without the MAP sensor and there isn't a generic replacement or workaround that will fit the bill.

This is a very sensitive item that's very carefully calibrated at the factory before it's sealed up. There's a 'well known' adjustment screw and another 'not as well known' adjustment nut (or screw... hmmm... been a while) inside. The exact placement of the diaphram is really important to get just right, or the input the MAP provides to the ecu will be incorrect, which will result in the incorrect amount of fuel being supplied to the engine.

I'm certainly not saying to not try rebuilding it - just that it's not something as simple as rebuilding a starter or an alternator or.. whatever.

Hope that whatever you do for a solution that it works out well.

Best,

Cameron
Rose City