low oil pressure issues

[dud3iknow]

hello everyone,i'm new to this forum and need some help with my tempermental
1998 ford explorer 4.0 ohv.
let me start by sayin my oil pressure never worked and i never had a problem with the truck. I currently have 162,000 miles and have had regular oil changes
I recently changed oil change locations due to them closing. I went to LMC lube
here in nyc and now i notice that it has a knock/ticking.
let me just state that the coil pack,plugs,wires,coolant tem sensor and belt
were all changed 3 months ago.
my guage reads NO oil level,so i bought a new switch at autozone and now with the key on position (car not running) the level on the guage goes to the middle and as soon as i start the car it drops to zero and i get the check guage light. i checked wiring and all seems normal no rot or corozion.
I went to LMC lube for an oil and filter change and now it has a knock/tick
in engine area but it seems to be lower engine area.the oil that was used was castrol syntec blend 5w30 and aome unknown name filter (that was leaking)
I read on here that it may be the oil so i just swapped it out with some valvoline thicker oil and it seems a little better but still have the knock/tick.
I just purchased a motorcraft oil filter and am going to swap it out today but any advice or opinion would be appreciated as i never had this problem before and i dont want to drive around with no oil pressure,the truck runs awesome otherwise.

 

[1Aauto]

You may want to check the oil pressure sensor. If they go bad they can give you a false reading on the gauge.

 

[dud3iknow]

thanks for the reply.
one question because now im a bit confused.
I changed the oil pressure switch, is that the one your talking about?
its on the right side lower block area.has a green/white wire on it
if so i changed that already.

 

[ranger7ltr]

Oil pressure sending unit...

Is mounted on the front drivers side of the engine block with a plastic connector on it...That is the unit that drives the oil pressure gauge on your dash...

 

[dud3iknow]

yea thats the right one, I changed that and im still reading no pressure while car is running when its just the key on position the guage goes to the middle and when i start it it goes to zero pressure and has a little knock like the lower engine area or by the driver and passenger area.swapped out the no name filter for a motorcraft and still have the slight knock.

 

[buckwill]

what i would do is first get a good mechanical pressure guage and put it in place of the electrical sender, find what your actual pressure is,, then if its good u can procede to find what electronic gremlin is, but if your engine has no or little oil pressure then it will get much worse

 

[dud3iknow]

thanks buckwill will check that later on today and let you know the results,but someone else told me to check the cam sensor also.

 

[dud3iknow]

ok i think i figured where the noise is comming from..
its the friggin transmission by the tranny pan.
now next step is to drop that tranny pan and see whats going on in there.
i'll keep you all posted.

 

[buckwill]

if i had a friend who had a knock noise and an iffy oil pressure guage,, id urge him to make sure he had oil pressure

 

[JAMES209]

Be sure you have the correct replacement part. The one for the guage, not for the op light. AZ sold me the wrong one to me last Jan. Plus they sold me the wrong fuel filter. He blamed the computer.LOL

 

[dud3iknow]

ok wait,there are 2 different ones?
can you please tell me because im clueless to my ohv having 2 switches/sensors.
and i removed the flexplate cover and it in fact is my flexplate rattling.getting ready to change that today.

 

[TonyV2000]

I replaced the oil pressure sensor on my 5.0 with a unit I purchased from NAPA. The thing worked for about 3 weeks. Then the gauge started to bounce around so drastically and so erratically that the needle somehow went past the peg on the gauge! I replaced the sensor again with a Motorcraft SW5192 and the gauge works fine, albeit a little different!

Purchase OEM!

 

[dud3iknow]

thanks for the photos tony mines does the same think im going to go buy a new one from motorcraft like you did and see what happens.ill keep you posted.