Where would you suggest that I could source a replacement return spring? Mine is damaged (and very rusty)...I'm thinking that aftermarket options would be suitable...just wondering if anyone in the group had already investigated and solved this problem before.

@Terrapin Z

I would look at somewhere that deals with Weber DCOE, Mikuni PHH's etc as a point to try.

That looks like the spring and bracket off of a Datsun EFI throttle body.

78 280Z

Should not have a problem finding one here on this site.

Thanks Yarb....I'll place a "Wanted to Buy" post on this website...

In the attached photo I've drawn two black arrows next to the parts I need. We've already discussed the larger spring. Now my new question concerns the part identified by the other black arrow. From reviewing other sources, I'm pretty sure there are supposed to be two of these small "washer" looking parts...one positioned at each end of the smaller spring when it is installed on the side of the throttle body...along the "axle". Mine only had this one washer...so I'll need to locate a second one. Additionally, when I removed these parts from my throttle body, some small pieces of broken black plastic fell out from inside the smaller spring...I'm thinking that originally there was some sort of plastic spacer inside the spring that deteriorated over time. Can anyone confirm this? And perhaps post a photo of what this plastic part looked like?

That’s correct the plastic piece has done its job. Not a show stopper by any means. Someone on the forum will hook you up.

Just had to dig for an old TB. 

My spring had this little piece of rubber inside it. 

The collars and pin need clean up. It needed a little heat to get it apart. The collars are metal on my set up. No plastic parts that I saw. 

Car parts manual only identifies the spring, and does not show the collars or pin.

Doesn’t look like the 78 model setup.

Perhaps not, I had some loose TB's and do not know what there were off of. I thought the spring and collars looked the same. 

The 78 car I bought came with a 75 engine. It had the N42 non EGR manifold at least. 

Terrapin, I think those parts look perfect for any of the 280s, including the 78.  I believe the linkage attachment piece is from a ZX, not a Z. Details a couple posts below.

Exploded 280Z throttle body for reference:

Edited July 22, 20231 yr by Captain Obvious