Hi. It's been like two years since I posted here. Had a weird issue happen just now in my 90 vert with 118K miles.

As I decelerated and clutched in, the revs dropped to idle speed, but dipped a little lower than usual, like maybe 4-500RPM, and all the idiot lights came on (except the airbag light). The car did not stall, though I thought it had so I popped the clutch in second gear going around the corner. Of course this made the revs climb back up abruptly, and the idiot lights dimmed heavily. So now, I'm playing with the revs at 40 MPH in different gears. The tachometer is acting light a rotary light switch. At this unusually low idle, the idiot lights are full bright, and as you rev it up the idiot lights smoothly decrease until at 3500RPM they are completely dark as normal.

In all other ways the car runs completely normally. It starts easily, makes power smoothly, the headlights stay bright etc. Just a low idle that seems close to stalling and the idiot lights dimming with revs.

The only things you may need to know about, electrically, are that I have an FD alternator conversion, and the fuel level sender is messed up and only reads correctly for the full half of the tank.

Thanks in advance for your help.

 

Sounds like the alternator may be giving up. Check it out, I've had similar issues in cars in the passed.

 

Thanks jgrewe. My memory tells me that I've only had this alternator for maybe 5000 miles? I bought it from someone here named Silverotor I think. Still available I hope, because the FD upgrade did make the car run better.

 

Yep, all the lights on = failed voltage regulator.

 

Can the voltage regulator be replaced or do I need a whole new alternator? And if I do, is Silverotor or anyone else still here that does the FC nodded FD Alts?

 

It's inside the alternator, so you'll be replacing the whole thing. And how is your FD alternator modified? The only thing you really have to change to use one on an FC is the pulley. Loosen the nut with an impact gun, and swap it onto the new alternator. You can PM silverrotor too: https://www.rx7club.com/members/silverrotor-11532/.