I think that should be the speed ‘ref’ sensors (reference)

Check all engine bay hoses - breather and vacuum.

There is a circa 1” wide vacuum hose that joins the chassis in front of the engine, onwards toward the brake booster. Do check that - mine fell apart upon inspection ..

http://forums.pelicanparts.com/uploa...1552748731.jpg

Every 30 years rebuild your axle halfshafts.

Get the intake smoke tested, find vacuum leaks early before the cause real damage. Most cars I look at these days have some sort of intake air leak.

fuel lines, fuel lines, fuel lines. My 1985 has had two major leaks and I found the third luckily before it happened. You say they were checked...but if they are original and 35 years old, I would change them before it is too late. My car has 250,000 miles and still runs fine.

I just did this...

http://forums.pelicanparts.com/uploa...1612830836.jpg

http://forums.pelicanparts.com/uploa...1612830836.jpg

http://forums.pelicanparts.com/uploa...1612830836.jpg

So, I wish I'd had this...

https://www.rsrproducts.com/product-page/rsr-products-rear-sway-bar-mount-gusset-kit

New WEVO mounts getting welded up next week.

Agree on replacing the 2 reference sensors, CHT, fuel lines, intake gaskets and also check the distributor bushings. My bushings at 100K were fine however, my brother in laws 911 at 100K found that the rotor was beginning to touch the cap due to the upper bushing being worn out. And of course - yes, drive it!

This!