What does a blinking oil light on a 2.4 mean?
 

I have been looking at a 73 Targa with the 2.4 in it. Runs well but the oil light is blinking and the oil pressure is bouncing from 10-25 at idle. Is this an oil pump, sender, engine gone bad? When revved it spikes immediatly but light stays on. What could this be?

What color is the light?

It is a red light flashing at the top of the guage that has the oil pressue on it and then there is a solid red light at the bottom of that guage that is on always (i think thats parking brake). Any ideas?

One red light is your parking brake (flashing) and brake warning from the master cylinder (solid)

You appear to have the optional oil temperature/pressure gauge (temperature dial on the left, pressure dial on the right with red lights top and bottom).

The top red light indicates a brake problem; either with the hydraulic brakes or the cable operated parking brake.

The lower red light indicates an alternator/fan belt/fan problem. Sometimes this light may flicker at lower rpm when one first starts the car but it should go out and stay out after increasing rpms

The oil pressure you report at idle is okay; the bouncing may be from an unsteady idle or a loose wiring connection.

You should seek out and address the causes of the brake and alternator lights coming on.

Cheers, Jim

So the car is not fine though. It will likely need alternator/regulator work along with brake work. I am assuming it will need a new alternator, rebuild of four calipers, four new rotors, new pads, new rubber lines, hard line inspection and replace, along with a new master cylinder.

This topic is really in the wrong forum.

The alternator light can mean numerous things: slipping (or even missing - but I doubt this as the engine would soon over heat and fail) fan belt, failed or failing voltage regulator, failed or failing alternator brushes or bearings or perhaps just a loose wire somewhere or failure to install a resistor in parallel with the generator light if the alternator was changed out to an internally regulated model.

The brake light can mean: the mechanical parking brake is not releasing or the switch on the parking brake is bad or mis-adjusted, or it can also mean a brake fluid leak. The first place I would look for a brake system leak is in the rubber sections of the brake lines before each wheel, then the master cylinder and then the wheel calipers. The brake light being lit does not imply all the brake work you listed; only a inspection and road test can confirm that much work needs to be done.