Need some help and direction. Headlights flicker sometimes over bumps. Found that if I tap on my relays with the lights on the lights flicker and the relays chatter. This is a 71 which I upgraded to relays . Oddly I have my fuel pump on a relay also and I can get it to chatter also by tapping it. Only thing I think they share in common is the power source. The main power comes from a power strip that I have connected directly to the back of the alternator . Pretty sure the grounds are different between the headlights and fuel pump. 

Appreciate any testing methods 

There is sometimes very little to be gained by simply looking at electrical stuff, but...

Can you take a couple pics of the parts in question anyway? The relays? The alternator?

Do both headlights consistently flicker at the same time or just one?

I have each headlight on a separate relay, so good point whether they both flicker . It seems both do


Sent from my iPhone using Classic Zcar Club

Sent from my iPhone using Classic Zcar Club

The only common factor with all these is that they are grounded to the relay mount I made. Maybe insufficient for the power


Sent from my iPhone using Classic Zcar Club

check your ground for clean and tight. you might add some dielectric grease to stop corrosion too.

Problem solved 99% sure. So I pulled the relays off the sockets to remove sockets and install new grounds. Then I noticed the trigger wires on the headlight relays about falling out of the sockets. These were part of a kit and I installed all the wiring. So I guess I didn't get the trigger wire pushed in until the spade catch caught on the socket. Pushing on my relays caused them to about fall off, so I was having a weak trigger signal . Must of been like this for years , but just now really started acting up. Now I can bang on the relays and nothing happens


Sent from my iPhone using Classic Zcar Club

Excellent! Glad it was that simple.