so i just bought an '88 base(i think) firebird a few days ago, and am still getting used to it after driving my '72 lemans wagon around for the past years. now, everything seems to work quite well except for 2 things. first of all, under my light switch, there is a little **** on the dash. what does this **** do? i've played with it, and nothing happens from what i can tell.

the second thing is, when i'm driving, my oil pressure stays at 80, and when i'm idling, it goes down to 40. the car originally had a 2.8L v6, but the previous owner said it had a 3.8L v6 transplant. i think he meant 3.1L, but i don't know how to check on that. i'm wondering if the oil pressure gauge is malfunctioning, maybe it doesn't know how to read the new engine's normal oil pressure? i've got a small oil leak, but i would think that would make the oil pressure drop, not rise on acceleration. i've never had working gauges in my other car, so i don't know what the gauge is even supposed to do, so this could be perfectly normal for all i know.

everything else seems good though, the water temp hasn't gotten above 200F and the volts hovers right around 13 in the middle of its gauge, the tach works, the speedo starts working once i get up to 20, and then it works until i shut the car off where it does the same "frozen til 20" thing. the odometer and trip odometer don't work, but neither of those are really big deals. i just wish pontiac had put the glovebox on the dash instead of in the rear hatch. i'd much rather have a glove box than a hatch box.

 

That little **** could be you instrument cluster dimmer switch- next time you are driving at night, and are stopped at a light, turn the little **** and see if your dash lights get dim (mer).

 

nope, my panel dimmer switch is a vertical wheel just above the headlight switch. when my headlights are on, and i use the panel dimmer, the dash lights come on, and when i click it into it's upmost position, the dome light comes on. when the headlights are off, the panel dimmer just controls the dome light. i've played with this mystery switch with headlights both on and off, and i haven't noticed anything. doesn't mean nothing's happening, but i haven't noticed it if something is happening. my car doesn't have an owner's manual, or else i'd just look in there.

 

Post a picture of it.

 

the first picture shows where it's at on the dash, the second one is just a zoom-in on the **** in question.

 

Looks aftermarket, trace the wires.Maybe not hooked any longer.

 

x2...looks like a gain control for amp,or glo gages? if the plug looks like a phone jack/cable then it was a remote amp gain control...

 

That is to set the PSI on the pass side ejector seat !!! be veeery careful with that !!

 

well, the car has an aftermarket stereo system, and it's wired up for an ampilifer in the rear hatch, so i guess it must be for that then. mystery solved, thanks guys.