Various problems with 1990 Buick Regal GS

#1. Whenever I accelerate my volt gauge will down into the red briefly before going back to normal. Not entirely sure what to do...



#2 When I push on the brake pedal I only have 1 light coming on the right while I have no left or center brake light coming on. I tried replacing the bulb to no avail but when use my left turn signal The light will come on just fine.

EDIT: I would like to add that I also have no back up light coming from the left side either.






Thanks for the help.

Welcome to AF.

Check the condition of the drive belt. Also, have the battery tested and check the alternator for proper voltage output.

On the backup lamp and brake lights you may have a bad Multifunction Switch at the steering column. Bad contacts. Look for 12 volts at the lamp sockets and make sure the ground is good. Check all relevant fuses.

If I had someone do all the testing and fixing, How much should I be spending?

Labor costs will vary but electrical labor rates can be high along with the total time it may take to troubleshoot and resolve the issue(s). For example, the GM dealers in my area charge $80/hour. Best thing to do is take it to a few general automotive repair shops and get an estimate to give you an idea of the possible cost. Also, the MFS switches can be expensive but there are aftermarket ones available.

Just want to update.

Today I looked at the lights, 1 was bad and the backup light was fried. I replaced the backup bulb and the brake light. I have both reverse lights working but the brake light wasn't fixed.

I'm getting the whacky voltage looked at tomorrow.