VOLT Gauge Lowers in Reverse..?

[solaris=amazing]

The first 1/2 a second when my car is put in either drive or reverse, the rpms go just below 500-and my light dim slightly. Along with that, my VOLTS gauge decreases a hair. Why is that..?

Also, are these idle #'s correct, or good.

Park 800
Drive (foot on brake) 650
Reverse 600

I adjusted my idle back to the above stated rpms.

2 weeks ago, i adjusted my idle to be higher because my car would stall when put in drive, or reverse. Due to a bad MAF sensor. I adjusted it by the screw on the throttle body.

Should i keep my idle higher so the lights, and volts gauge don't dim when put in reverse or drive..?

1995 4.6 V8 tbird

[solaris=amazing]

BTW, the rpms drop to just below 500, then back up to what i stated i have it at. It doesn't keep on bouncing.

[solaris=amazing]

Nevermind guys. It's a voltage surge from the power steering.

[sierrap615]

also, at low RPMs the alternator can't put out a strong 14 volts, its just not spining fast enought

[solaris=amazing]

Exactly..thanks..

[curtis73]

Its not a power surge from the power steering since that is entirely hydraulic.

The reason your voltage drops is because your RPMs drop. The alternator is equipped with a pulley that allows it to make juice at idle but not overspin at redline. Usually the cutoff is right around idle, so when you put it in gear it can't make the juice to keep up. The voltage gauge reflects that.

The reason your voltage gauge falls even further in reverse is because (in addition to the drop in RPM) you're adding two 15w light bulbs to the party.

Its not a flaw at all and doesn't need to be corrected. Its normal. If you're worried about it, you can find the max speed your alternator is rated for, and select a smaller alternator pulley size that will max it out at redline. That will make it spin slightly faster at idle and may correct the drop in voltage.

[solaris=amazing]

Man, you guys always make me feel good :-)

THANKS curtis.