Oil pressure drop at idle, only in drive and when warm????

[Mattl12]

1990 Ford Ranger 2.9 V6
73000 miles
Heads and head gaskets recently changed, cooling/radiator system almost entirely new as well.
Changed the Oil pressure switch already. Changed oil and filter yesterday, high mileage synthetic blend 10W-30. Drop off only happens when warm and in drive, hitting the gas makes pressure go backup. No change in sound/noise. Just got first hiccup/vibration today.


Haven't guaged the oil pressure yet. OBD connection is clogged as it was opened the first time today, needs to be cleaned so I have no codes.


Thoughts????

 

[adsm08]

Sounds like it is time for an HV oil pump.

 

[Mattl12]

Isn't replacing an oil pump on a 2.9 ranger a major job???

 

[Mattl12]

Would you drive it or is this a park it and tow ordeal?

 

[alwaysFlOoReD]

I would put a real gauge on there and see what it says.

 

[Paulos]

Mine has 300K+, runs at 40psi on the highway and sometimes 15-20psi at idle. Surprisingly, I have no ticking noise. I just don't stay still long enough for it to sit and idle much when it's warm . Mine needs a rebuild. And cam bearings.

 

[Mattl12]

I would put a real gauge on there and see what it says.

Don't own a gauge and don't know what to look for/read it if I did. Gauge plugs in right where the pressure switch I just replaced screws in right? What I'm finding is the switch says there is pressure over 5 or 0 pressure (Dashboard "Gauge") and nothing else. Unless the repair costs are significant enough to junk the truck I will put on an after market "True Gauge".

 

[Mattl12]

Mine has 300K+, runs at 40psi on the highway and sometimes 15-20psi at idle. Surprisingly, I have no ticking noise. I just don't stay still long enough for it to sit and idle much when it's warm . Mine needs a rebuild. And cam bearings.

Getting on the gas seems to keep oil pressure level enough, like I said only at idle and in drive. Check engine light is coming on and off intermittently and that freaks me out.

 

[Mattl12]

Oh yeah does an "Electrical Brown Out" mean anything to any of you as far as oil pressure readings? When I found a discussion that matches my problem almost exactly that came up, unfortunately there was not more to that?

 

[Uncle Gump]

Yes a mechanical gauge will screw in where the switch is located. Get a gauge in there and see what the readings are.

Paulos... 15 to 20 psi on a hot idle sounds pretty good to me actually...