Replacing Dummy Oil Pressure Guage

[MustangDiesel004]

I have decided to replace the factory oil pressure guage with a regular guage that gives an accurate reading on actual pressure anr not what the ecm thinks. Where would I locate the sending unit? Could I just put it in place of the factory unit o rwill that throw a code?

 

[HBarlow]

We have no idea what truck you own.

The answer would depend, in part, on what truck you are inquiring about.

 

[J.BURCHFIELD]

All I did was go to Ace hardware and get a brass tee and put it between the block and the original sender. It took aprox 6 feet of hose to reach where I mounted the gage on the dash next to the ash tray. It requires no sending unit, the gage (mechanical) works off of the oil pressure and gives you a true reading. Get a good quality gage that will read up to 100 psi. It will show 60 psi on start up in the summer and more in the winter depending on where you are. You will need a special socket to remove/replace the original sender. I think NAPA has them. At idle with the engine fully warmed up you will see 20 psi and if you sit at idle for a while on a hot day it could go down to to 15. Then the chimes go off which scared me before I put in the mechanical gage. I replaced the original sender a couple of times but it did not keep the chimes from going off. I even increased the idle to no avail. With the mechanical gage a quick glance and I know all is well.

 

[Matt400]

Just add a separate gauge & tap into the top of the filter housing. Leave the stock one alone or you will get warning chimes. Besides it becomes a back up warning in case you don't see pressure has dropped off.

 

[MustangDiesel004]

Oil Pressure Guage

Thank yall for the info. I've been getting a lower reading for awhile on the factory guage and just found out it really isn't a guage after all. I never thought to tap into the top of the filter housing thanks again.

 

[J.BURCHFIELD]

I may be wrong but I do not believe that a true pressure reading can be had from the filter. The vein that the factory gage is tapped into I believe is the place to get the highest reading. It is the closest to the oil pump.

 

[DaveHess]

I tapped my oil temperature gauge into the top of the oil filter housing and take my oil pressure from the galley that runs down the left side (Drivers) of the engine. There are I think 4 plugs along the length of the block. I chose the one directly above and slightly behind the ECM. It did turn into a small nightmare to put it all together because of the reach but with the fenderwell removed (easy) and a lot of patience, I have a nice setup and accurate oil pressure readings. The factory does "follow" my aftermarket gauge. I get a little over 60 PSI when cold at idle and a little under 20 PSI when hot at idle. It's the hot that was misleading to me as my factory gauge would show about halfway between the "40" and the lower heavy mark. The only thing I noticed is my aftermarket is a little slow (and I mean only a little) to come up on start. I am using an Autometer Phantom electric and I mounted my sending unit about 24" from the engine and attached it to the block with a braided hose. I did this to isolate the sender from engine vibration. Just my. 02

 

[MustangDiesel004]

I finally mounted the aftermarket guage. I tapped into the top of the filter housing and get a good reading. Thanks for all the help.

 

[Allnew2Me]

On my truck, a second gen, the PCM controls oil pressure readings and the story of the PCM not showing accurate pressure is only partially true. I am guessing the same thing applies to the third gen trucks.



According to the service manual for my truck, the only time the readings are, in the words of the manual, "consistant with customer expectations" is when the pressure is below 8. 5 psi or over 109. 5 psi. These readings show the gauge in a preset position. All other readings are the actual pressure sensed by the PCM/sensor and shown accordingly. How accurate the gauge is, is of course another issue.



The low pressure warning comes on at 8 psi and the high pressure warning comes on at 109. 5 psi.



I am all for more gauges but what is the reasoning for the additional oil pressure gauge unless you don't trust the stock setup?

 

[MMeier]

I finally mounted the aftermarket guage. I tapped into the top of the filter housing and get a good reading. Thanks for all the help.

So, what are your readings compared to the stock gauge?

 

[MustangDiesel004]

At around 40psi on the stock guage the aftermarket shows the same. But beyound that I've seen as much as 60 psi and as little as 20psi. I mounted this guage just for peace of mind and because I dont trust the electric guage. I havent had problems with the factory guage but it's nice to see the actual pressure and not what the pcm sees from the electrical signal.

 

[steved]

I may be wrong but I do not believe that a true pressure reading can be had from the filter. The vein that the factory gage is tapped into I believe is the place to get the highest reading. It is the closest to the oil pump.

Most owners that install the sending unit at the filter aren't worried how much pressure they have, but that they have any pressure at all. The OE unit will show pressure for several minutes before it "decides" you don't have any pressure.



I have it near the filter, all I care is that I have some pressure... and believe it or not, there is little difference between the two readings (factory "fake" guage and the aftermarket.

 

[steved]

On my truck, a second gen, the PCM controls oil pressure readings and the story of the PCM not showing accurate pressure is only partially true. I am guessing the same thing applies to the third gen trucks.

This only applies to later 2nd gen trucks and those that have been reflashed... earlier versions are "real" readings...

 

[GSchneuer]

Replacing Dummy Oil Pressure Gauge

What size I. D. pressure hose did you all use 1/4, 5/16 or 3/8th.



Thanks for your help,

Gary

 

[steved]

I have mine in the supply line for my bypass... its only 1/4 inch hydraulic line...

 

[MustangDiesel004]

I used the 1/8 inch plastic tubing that came with the guage.

 

[WOT]

This would seem like a good opportunity for the smarty or other programmer to rewrite the code to actually show the REAL pressure. Of course that assumes the input to the ECU is more than just a bit (on/off) reading and that you would have to replace the sending unit with a real one.