[bonestockE36]

SAP is only run the first couple minutes of a drive cycle. If it doesn't test ready then, it will not set later in the drive. It literally should be one of the first readiness codes to clear.

An older MS42 doc says SAP only runs when coolant temp is -10 to 40°C and there are no codes for SAP. Are the temp sensors reading correctly?

Besides this, in Texas is looks like you are allowed two test to be not ready and still pass? (something specific about non continuous tests) I know in IL they allow one, because in winter evap will not be set in most cars.

 

[bonestockE36]

O2 are used to check the SAP and evap purge are working. Are O2 working correctly now? Do you have a CEL right now?

Have you read the coding data (IDENT tab I think) for the DME with INPA? Does it report a VIN, Software number and assembly number?
Does NCS expert read VIN from any available module?

 

[bonestockE36]

Apparently year 2000 can have both the ODBII under dash and the round one under the hood. The cap on the round one must be in place, for the dash connector to work.

 

[bonestockE36]

The only thing left is checking wiring. I've chased problems in machinery to connectors, broken PCB traces, etc. It sucks. I'd start by inspecting and reseating every connector I could find.

 

[bonestockE36]

Check wiring for the temp sensor. Drive cycles will not fix this, you need to find what's actually wrong. I know some states have to read the VIN, even if OBDII is working.

When you bought it did this car come from an emissions tested area? I'm wondering if some stuff was coded out to stop CEL. I don't have any ideas for no comms on the OBDII other than making sure all the pins are pushed in to the connector. I'd also reseat the DME connectors.

Two years ago I took the Odyssey for IL emissions they said they couldn't connect to the ECU. Passed me on no active CEL and said next time it would be a fail if they couldn't read it. I never did anything as I had no trouble reading OBDII. Last test was no trouble.