Slow Oil Pressure Drop

[BushyTea]

Well I have a 66 mustang and it has the 200cid with the auto backing it.

Well lately it seems that the oil pressure is fine but over time wether at idle or driving the oil pressure slowly gets lower. It's nothing drastic either, just slowly goes lower and lower.

Anybody had an issue like that? I have read some threads with no pressure at all or sudden drop but couldn't find anything where it slowly dropped.

Thanks!

 

[bigcatchdaniel555]

in my experience it could be 2 things one more common. When my oil pressure sender went bad i would have full pressure for the first 10-15 minutes of driving then it would drop consistently to nothing this scared me until i replaced the sender. the next could be oil break down. when thin or cheap oil gets hot it tends to become more runny resulting in a small pressure loss i solved this by using sythetic oil.

 

[fordconvert]

How long have you had the car/motor? It is normal for pressure to drop as the oil heats up and thins out. What weight oil you running? What type of climate you in? If it was a crusty dirty used engine and you have been changing the oil often and or using a flush product you could be cleaning the gunk out thereby lowering the pressure a bit due to wear. Bad sensor or gauge is also not out of question. Go to a parts store and pick up a cheap ($20) mechanical gauge, put in a T if you want to run them both and tape the mechanical one to the hood if you have to just to compare readings.