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I have a 1995 7.3 and it is my first diesel engine. I have been getting sporadic oil pressure readings on the dash gauge. I have been told on another forum that the sensor on top of the HPOP is really nothing more than an "on" "off" switch that tells the gauge to read mid range when pressure is above about 6psi. It was suggested that I ground the switch to make the gauge read mid range at all times but, I don't want to trick my gauge (I'd rather just ignore it).

I am trying to locate the oil pressure sending unit So I can replace it. I feel like that might make a difference for this issue.

Also, Fuel Bowl removal, I'd like to get good directions on how to remove my fuel bowl. everything I have been able to find talks about either a 99 and newer 7.3 or they say my fuel restriction sensor is on the back bottom of the bowl. My fuel restriction sensor actually is on the fuel pressure manifold which is attached to the driver side of the fuel bowl.

Please give me all the info you can.
 

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Is the Oil pressure gauge bouncing on Idle but is fine when your running, i having the same prob but i haven't got round to fixing it..........
 

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No. RPM doesn't change anything either. Nothing the engine does seems to change the reading, it just goes from good to low and back to good with no method to the madness. I know there is a bypass on the oil filter housing that allows oil to flow incase of a clogged filter or if something is blocking. I think the Oil pressure sending unit is attached to the same housing and I am suspicious that the bypass is opening because that unit is failing and the oil pumps are working off their own suction (I'm not sure if that makes much sense).

Below is a link to the other forum I posted on:

Sporadic oil pressure readings. - Ford Powerstroke Diesel Forum
 

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The oil pressure sensor is located on the top of the HPOP. You can take it out and use a real gauge, or if you want, you can use a port down where the filter attaches. I don't have a picture of the gauges I installed on my buddies '01 but we used the port at the filter.
 

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I may have a photo in my pictures in my webshots pointing it out will have to check

Well i have an engine photo but I did not point out everything.

Looking at the engine from the front, find the HPOP resivor, reach over the top righthand side (towards the drivers side) and there will be a sending unit threaded into the back of the resivor. That is the oil pressure sending unit you are looking for. The one directly on top to the left is the EBP sending unit and the one directly behind the OP sending unit threaded into the oil rail on the drivers side head is the IPC.
 

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Reread my postings from the other forum linked above! (yes I'm on this one too). There is no low pressure oil "sending" unit that is monitored by the computer. The bypass on the oil filter header adapter will open due to a clogged filter (nothing communicates with it to tell it to open ... it jsut opens when the spring pressure is exceeded). There is also an oil pressure regulating valve on the block side of the oil filter header adapter (also another spring-type setup similar to the fuel pressure regulator). If you really must know what your OP is, hook up a real mechanical pressure gauge and watch it. The factory gauge is garbage and doesn't tell you much. Either the switch is bad, the wiring is bad, or the gauge is bad (teally narrows it down doesn't it? :) ) Been there ... done that. Cheers!
 

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There's a write-up somewhere on one of the forum sites, showing how to make the gauge a real gauge. You solder in (or perhaps remove?) a resistor on the back of the gauge head, and then I think you also install a different sender, one that's an actual variable resistor rather than just a "switch".

If you go aftermarket, I would NOT recommend a mechanical gauge. That requires a capillary tube containing oil to be run through the firewall and into the gauge head. If that tube fails, not only would it be a fast oil leak, it would be, er, not a pretty sight inside the cab. There are electrical aftermarket gauges, with a variable resistor sending unit.
 

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Look in the IDI forum. Drinkypoo has posted the link in a few threads.

As for the aftermarket, I agree with the above, even though the capillary tubes are tough, I opted for electrical to make sure I didn't have to worry about a gusher.
 

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Here's the link to the "Real Oil Pressure Gauge" article. I did it on my 94 and wasn't really satisfied with it as you can't find a sending unit that matches well with the factory gauge. Yeah, it moved with RPM and temperature, but it wasn't that useful to me. I went with an aftermarket gauge for a while, but eventually I just went back to stock and added a tranny temp gauge instead. Cheers!
 

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^^^^^ +1; the thing to keep in mind about our trucks is that, if the lube oil pump ever fails, or there's an obstruction, or for whatever reason the oil is not sufficient to lube the engine (which is what a low-side oil pressure gauge is all about), LONG before it becomes critical to lubrication, there will be insufficient oil pressure to run the injectors hydraulically, and the engine will stop anyway. So the low-side gauge is of little value for us.
 

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Installl a new sensor/switch.
Autozone
Price: $9.99


Duralast/Oil Pressure Switch

Part Number: PS164

Just had to do it to mine. Readings were very low to ok to the needle jumping. New switch everything is good again.
 
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