Oil Pressure!!!!!!!!!!!!!!!!!!!!!!
badassfocus1101
03-04-2006, 10:05 PM
88 f-150 302 5.0 V8 5spd manual.
start it up pressure is fine, drive it around and it gets warm (normal temp) oil pressure drops. well not while driving unless its a 35mph zone and im in 4th, but if its warm and im at a stop light, oil pressure drops to 0 and engine idol drops reallllllllly low...what is causing this?
me and a buddy figured maybe the rods and main bearings?
cam?
burnt valves?
collapsed lifters?
clogged oil screen?
bad oil pump?
start it up pressure is fine, drive it around and it gets warm (normal temp) oil pressure drops. well not while driving unless its a 35mph zone and im in 4th, but if its warm and im at a stop light, oil pressure drops to 0 and engine idol drops reallllllllly low...what is causing this?
me and a buddy figured maybe the rods and main bearings?
cam?
burnt valves?
collapsed lifters?
clogged oil screen?
bad oil pump?
ModMech
03-05-2006, 06:55 PM
Bad oil pressure SWITCH.
You see, you do NOT have a true oil pressure gauge, but what is commonly called an "idiot gauge" because it is more like an idiot light, on or off.
Below about 6 psi of oil pressure, the SWITCH is closed, and the "gauge" reads "0" psi, above about 6 psi the gauge reads about 40% to 50% "scale".
Most likely, the switch is just bad. It is located near the oil filter, and has ONE wire going to it.
You see, you do NOT have a true oil pressure gauge, but what is commonly called an "idiot gauge" because it is more like an idiot light, on or off.
Below about 6 psi of oil pressure, the SWITCH is closed, and the "gauge" reads "0" psi, above about 6 psi the gauge reads about 40% to 50% "scale".
Most likely, the switch is just bad. It is located near the oil filter, and has ONE wire going to it.
badassfocus1101
03-05-2006, 11:25 PM
thank you......
miwise
03-06-2006, 01:08 PM
I have the same problem and the dealer said that it was bad main bearings, but I think it could be the high pressure relief valve. I won't know until I have it truely diagnosed at my mechanic and he takes off the oil pan.
badassfocus1101
03-08-2006, 12:24 PM
alright well thansk for the advise guys, guess ill just drive it till i get the money to do a rebuild on it, thanks
Donut Dunker
03-10-2006, 05:41 PM
mine does the same thing, but it does not knock or anything, only its a guage, I was told that ford did not put the right resister in the oil sending unit wire ---- so your computer is not reading the actual pressure the sending unit has on it --------
you can buy the right resister ( cut wire - add in resister) , I found my local NAPA guy has it for around $25.00,
you can buy the right resister ( cut wire - add in resister) , I found my local NAPA guy has it for around $25.00,
Donut Dunker
03-10-2006, 05:43 PM
try the oil pressure sending unit first, thats the most simple fix, if you know someone that is a mechanic at a FORD dealer, they might be able to help ( thats how I found out ford goofed on the resister)
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