It's role is to preheat the catalytic converters so they can do their job right away on cold starts. Interesting that with the MS45.1 DME, the SAP has a MAF to monitor air flow.
If you eliminate the SAP system, you'll need to code out the SAP and the secondary O2 sensors... same as if you were putting headers on the car.
Also, If your state has emissions tests, It will most likely fail even though you have cats due to the fact that those two entries will be non-functional when they read from the OBDII port.
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