Hey everyone, just bought an '84 NA Z31 and I'm about to do a lot of work to the car. I just wanted to know what anyone thinks of this that can help me out.

Most of my dash lights come on and light up brighter when revving the engine a bit, and also dim or shut off if the rpms reach a lower point. This also happens with every other light turned on.

Here's a video to show more in detail what's going on:


Thanks in advance!

 

It sounds like the alternator is on its last legs. Most auto parts stores will test it for you and your batteryor you can do it yourself with a volt meter.

Rev engine to 2k and check output -- it should be around 14 volts (13.7v) at the battery. Turning on lots of electrical equipment should produce a similar dimming. You might see an idiot light come on such as the Battery icon, ALT, or check engine.

 

It sounds to me like the alternator is on its last legs. You can get this tested at an auto parts store along with the battery while you're there. Or do it yourself with a multi-meter:

Rev motor to a constant 2k and check what the battery is receiving. It should be close to 14 volts (e.g. 13.7v). Turning on lots of electrical equipment will produce a similar light dimming. Chances are good that the ALT, Battery or Check Engine light will come on.

Finally, it's always good to clean some grounds while you're in there.

 

Well I do have a new alternator along with a bunch of other parts. So good to know its most likely just that, and yeah Im gonna be cleaning all the grounds and checking connectors behind the dash and around the car when I get to it.

Hopefully I can fix the gauges on the cluster that arent moving.