I’ve got an oil leak that appears to be coming from the top of the engine it covers the bell housing and the starter. I noticed that there is oil between the heads in front , maybe on top of the intake manifold. It idles rough and I think I’ve lost a quart of oil in about 450 miles. Gas mileage is down to 10mpg but I do a lot of in town driving. Would this be something other than leaky head gaskets.

 

Welcome to the forum

Good to include the year and engine model with questions
2003 3.0l?

No on the head gasket if leaking oil was the only issue

Head gasket leaks can cause misfires and over heating, with loss of coolant

3.0l Vulcan engine heads don't have oil passages with pressure, the valve train is oiled via the pushrods and lifters
They do have oil drain back passages, at the lower edge(spark plug side), but with no pressure so really couldn't leak much oil

On passenger side rear of the block behind the head is the oil pressure switch it can leak, and with pressure

I would plan on redoing the valve cover gaskets also change the PCV Valve and clean its hoses, Breather hose as well, if there is oil in these then that oil can get into the engine and foul spark plugs causing the misfires
The PCV Valve prevents pressure from building up in the valve covers which forces oil out of their gaskets and also down the valve stems into the intake
So a clean and working PCV system is a must have

Pull all 6 spark plugs and keep them in order
Look at the tips, see what they tell you about conditions in each cylinder, Google: spark plug tip diagnosis
They can tell you A LOT about whats going on inside each cylinder

You could do a compression test while all 6 spark plugs are out, its good info to have when there are misfires and poor MPG


To test for a blown head gasket
Cold engine
Remove radiator cap
Top up radiator if its low, water is fine to use
Start engine
Watch rad cap opening
Might be an initial "burp" of coolant coming out in start up but then no more overflow
Let engine idle for a minute or two
Coolant should just sit there no overflowing
If so then head gasket is OK
If it overflows and continues to overflow you do have a blown head gasket

 

Thanks, I just finished reading through “ big oil leak “ and it gave me a few ideas. I took a bore scope to look around the cam position sensor and found oil up there. I’m going to check it with a remote camera to get a better picture and see if it’s the rear lower intake seal. But I’m going to check the oil pressure sensor also. Did I mention that I just changed the starter that was wet with oil. I’m not sure that the sensor on the passenger side would migrate to the driver side, but I’m learning a new vehicle and it’s been over 15 years since dealing with the ‘89 Ranger/Bronco Frankenstein my dad put together after I rolled the Bronco(also 3.0L).

 

I took some pictures of the leak it appears to be coming from the rear seal of the lower intake manifold on the driver side I’ve also changed the vacuum line that comes off the upper intake just past the throttle body and IAC sensor/valve which improved performance dramatically I’ll be getting the pcv valve and changing that along with the spark plugs that have a 0.1 gap. Boggles my mind that they’ve never been replaced but I guess people like abusing rangers.
Looking down on the cam sensor oil is driver side of sensor.

Lower intake manifold driver side of sensor.

Further on the driver side of manifold I think the oil is leaking from underneath the lobe