Chevy Nova Forum banner
1 - 5 of 5 Posts

·
Premium Member
Joined
·
3,360 Posts
Discussion Starter · #1 ·
So, my son's '75 El Camino passenger head has this sensor in it at the rear against the firewall. 350/4bbl Cali car, numbers matching verified LM1. I have not seen anything like this in a gen-1 sbc cylinder head...
Automotive lighting Hood Window Neck Automotive tire

The part with the wire and the blue terminal cover on it is what we're stumped on. Any ideas?!?
Automotive tire Wood Tints and shades Rim Gas


Passenger side pad stamping for ID...
 

·
Registered
Joined
·
491 Posts
My guess would be a temp gauge, but I don’t think there is any coolant passage there? Wouldn’t hurt to verify the cylinder head casting number. Chevelle.com has an excellent tech section, might be some kind of Calif emission deal.
 

·
Premium Member
Joined
·
3,360 Posts
Discussion Starter · #3 · (Edited)
@Midmo Joe yeah, that was my thought too... The head boss/shoulder where that sensor is has a bulge not like any other head I've seen... We'll pull a cover and get the #s off and look. I'll post up the findings. Thanks for the info!!
 

·
Premium Member
Joined
·
3,360 Posts
Discussion Starter · #5 ·
Mystery solved... My kid was in his Chevelle/ElCamino forum and some old salts knew right away. It's GM's crude attempt at a knock sensor used to shut off the A/C if detonation occurred while running. Simple and probably less than effective. His Elky has factory A/C so it makes sense...
 
1 - 5 of 5 Posts
Top