OK I found out that one of highbeams isn't out like I thought it was, the plug doesn't connect that well.

My question is, are all the headlight plugs the same in GM cars of the late 70's early 80's? The junkyard I go to has a lot of Caddies there with the same type of 4 x 6 1/2 headlights the 85 Delta has.

I think yes, but I want to confirm first

 

99.99% sure!

 

Sure, they're all the same, but why not just take 5 minutes to clean the corrosion off the one you've got?

Just use a small screwdriver to depress the retaining tab and pull the terminal out of the plug, and wire brush it clean (a Demel is great for this), then snap it back together.

- Eric

 

I don't think rust or corrsion is my probelm, the plug in question is very loose

 

So remove the terminals from the plug and gently squeeze them tighter with a pair of pliers.

- Eric

 

And another thing you can do is give the tangs of the headlamp a little twist (CAREFULLY) with a pair of pliers in opposing directions...this will give you a more firm connection... I have also done this to Muskrat's Alero with success...