QUOTE(rjames @ Jan 11 2024, 03:38 PM)

What's with the plugged adapter? Looks like it's coming off of the advance port on the TB... but I thought that the later throttle body's didn't have an advance port. My '75 2.0 didn't.
Click to view attachmentwell spotted.
i don't know too much about the 2.0 L cars.
but there was a difference between the calif spec and 49 states.
calif had EGR but 49 states did not.
and calif def had EGR vacuum initiated off "advance" port on TB.
Click to view attachment from what i have seen it was the 49 state 75 2.0L that did not have an "advance" port on TB.
neither version used timing advance from advance can on distributor.
only retard side. ( but
@JeffBowlsby will correct me if i am wrong).
i am more familiar with the 1.8s.
contrary to myth the 1.8s did not divide purely on model years when it came to the set up for advance and retard of timing and whether or not the TB had both an advance and retard port.
the 74 49 state 1.8 had advance and retard ports on TB and used both coupled up to the advance and retard sides of the can on the distributor.
the 74 calif 1.8 only had a retard port on TB and only hooked up the retard can on dist.
the 75 49 state 1.8 was as per 74 californian.
75 californian used the 74 49 states TB with both ports but hooked up the advance port on the TB to the EGR.
from what i can glean about 75 2.0s its a similar scenario.
advance port on TB hooks up to EGR on californian.
no advance port on TB for 49 state cars which don't have EGR.
not sure if californian 75 2.0 had the air pump and air injection either.
instead had cat and EGR. but not 100% sure. tech book that jeff bowlsy has on his website which i have looked at for the 1.8s has the 2.0 info in it.
seems to say they did with EGR and cat additional.
cars that exist today of course have mostly got all this stuff missing.
Click to view attachment its got the correct air cleaner for a 75.
has the connection plate for EGR.
which is blanked off in this case. as it should be for a 75 49 states.
and in other photos you can see it has the smog pump pulley on the fan.
seems to be in accord with the emissions sticker on fan casting and stencil stamp on tin saying its a 75 49 state.
but you and emory are right about the throttle body.
from what i can tell it should not have an advance port opened up.
either a 73/74 T/B or a 75 calif T/B?