The battery and oil pressure gauge pegs - 1987 Fiero GT

SOURCE: need to locate the ignition control module in my 1985 fiero gt

Take off the distributor cap, it is held on by two screws and has three plugs, 1 to the pick up coil, one to the computer, and one to the ignition coil.

SOURCE: oil pressure gauge pegged at120

Your gage is electronic I take it, buy or borrow a regular gauge and test it again. If the pressure is indeed 120PSI your oil filter is about to blow the cover off itself. This issue is most often caused by a stuck pressure relief valve on the oil pump. And indicates replacement is necessary.

SOURCE: 1992 BONNENILLE OIL PRESSURE READS PAST TOP GAUGE PRESSURE

Sounds like the pump pressure relief is gummed up or faulty. Try putting in a quart of marvel oil. If it does not get better in a couple of days, you may need to take the pump out and check it. Depending upon what engine you have, some have the pump located in the timing case cover...on those it maybe possible to remove and clean the relief. Get a manual and check to see where yours is located.
Avoid high rpm running while you have this problem as your oil filter can split open and you will quickly loose your engine oil.

SOURCE: I have a 1986 Fiero GT. Recently the lights in the

ya could have a loose wire

SOURCE: 1987 Fiero GT automatic trans. Won't turn over-ran

So no power anywhere? Nothing at all? I'm assuming the battery is fine since it ran the day before.

This actually happened to me one time in my fiero

What is happening is no power is getting to the car at all, no power is reaching the engine, lights, interior, etc.

This simply or not so simply means there is a severed connection from the battery.

1) Check BOTH positive and negative connections, make sure the posts are clean and make a solid metal-to-metal contact and see if there is power yet.

2) Check the power junction area (or whatever it's called) in the engine bay (on the passenger side wall near the battery). There are red wires
and such which supplies the car with power in this junction area attached to posts and inside of black plastic connectors. Look for worn or severed wires which may have come loose over the years.

When this happened to my fiero, one of the wires corroded and came loose from the post where it was bolted on and attached to other wires.

Just reconnect the loose wire(s), you may have to crimp new ends or whatever, but that should fix it.

If not, start hunting for where the 12v supply from the battery is cut off. Use a multimeter and good luck!