I just finished replacing the heads in my 97 4.0L Ranger and every thing went back in with no extra pieces, I was very happy about that. But I did have a random wire with the fitting on the end that is left over just hanging in the engine it is dark green with a white stripe...
Any ideas what this goes to?
I have driven it around and nothing seems to be wrong with it.

 

A single wire on its own with connector could be for the temp sender(for dash board gauge), by thermostat housing.

Oil pressure switch is also a single wire.

 

Ok thank you. I think it is the oil pressure switch because the gauge on the dash board is down at zero. Where would this sensor be located?
I know it has to be in the engine block some where but I am not saying it...

 

Drivers side of block lower front.

This is a video of how to change it so will be helpful in finding it

 

Thanks that video really helped.

 

Just replaced the cylinder heads and ever since the engine has a burnt coolant smell. And it has been leaking oil.
The oil I get... I am just going to have to find the leak but any ideas on the burnt coolant smell?

 

Where do you smell it?

In the cab(heater core)
At the exhaust pipe(head gasket)
In the engine compartment
Best bet is to warm up the engine so cooling system has some pressure in it then shut off engine, open hood, listen and watch.
Also squeeze the hoses and look at all hose ends, after engine work and re-clamping the hoses can crack.

Also check overflow hose for leaks.


Valve covers shouldn't leak at all but especially after being replaced, lol.
Make sure valve covers didn't get over torqued, the stamped steel covers will warp and leak oil, there is no "oil pressure" in the valve cover area, it's just gravity and a hole where gasket isn't tight that allows a leak.
The intake manifold has a good size gap front and back in the valley, you need to put silicone(which comes in the gasket kit) on those seals to prevent oil leaks.

 

The coolant smell is coming from the engine, not the cab.
I'll look at the gaskets this weekend about the oil leak.

 

Probably just a loose or cracked hose end.
Smell means it is getting on something hot and evaporating, so......look at the hot stuff