Lights flicker on my 1984 d150 pickup

The voltage regulator is bad. I think yours is mounted on the firewall, it's very lmportant to clean the mounting surface before you install the new regulator think of the mount as part of the circuit. I hope this helps, take care.

I'll try another regulator. Every time I put a new one in they overcharge like 15.3 Volts. I got a regulator that I can adjust and I can get the voltage down to 14.4 Cold. I think it still pulses at the amp guage when replaced.

I added ground wires to voltage regulator before but still pulses

Did yoy add the ground wires before or after you replaced the last regulator? Once upon a time years ago I found a Chrysler alternator rotor that had a piece missing fro the slip ring it jumped constantly but always charged. If all ok Do this. Start the truck, turn on all loads let run for a while then shut it all down, get to the back of the ampmeter Carefully feel the back of the gauge is it super hot, if yes clean the gauge studs and the connections on the wiring

I guess I'll have to pull dash apart for that?

If you don't find a problem there with the cluster out connect a voltmeter between the terminals connected to the ampmeter start the engine and see if the voltmeter fluctuates if yes back to the alternator if no replace the gauge. Take care

I don't think you can hook up o volt meter where an amp meter is hooked.

Yes you can don't worry, I've been a ASE Certified mechanic since the patches worn on work uniforms said NIASE. Needless to say I'm retired

I hit send to soon, the meters these days are actually wound as a shunt circuit so all the current in the vehicle doesn't have to run through the meter like all the old Chrysler products I used to see burning on the side of the road, ha ha and I can't stress the ground enough I've seen exactly this problem so many times that's why I stressed cleaning the base and firewall. Anyway the gauge is next in line

I'm sorry my iPad died. I will check this out tomorrow afternoon after the sleepover grandkids go home! I'm very thankful for all your help...Ken

By the way can I hook both amp wires together and install a volt meter somewhere else

Yes, jumper them together then connect the pos lead of the voltmeter to that connection and the neg to the cluster ground if you can find it. Take care.

I'll be here tomorrow have fun with the sleepover remember to build a tent in the living room if they're small enough.

Sorry the littles just left. Raining now so it looks like ill have to push the project off till further notice. Thanks ken