Installing an oil pressure gauge and need a hot wire.

[kcnizdodge]

Gentlemen, I am need of assistance. I am installing a new Auto Meter oil pressure gauge in an SRT-10 a-pillar gauge pod. This is an electric gauge and I have it installed in the pod in the truck. I have the sending unit installed and the wire run over to it, but not connected. Here is my question: the gauge instructions say to run one wire to the ignition so the gauge is only active when the switch is on. So where do I find the ignition wire to connect to? Should I find one coming down through the steering column and tap into that or is there a connection I can make out at the fuse center in the engine compartment? I thought I would check with the experts as I don't want to connect to the wrong wire and nuke the ECM! Geeze, the boss would be removing body parts!



Thanks for any assistance you can give, it is greatly appreciated.

 

[Matt400]

The cigarette lighter is a "keyed" power feed. Just curious- where did you mount your sender?

 

[MMeier]

Any reason in particular why you are installing an aftermarket gauge?

 

[Matt400]

Probably because he wants to know the actual pressure. If the OEM gauge reads anything, all it means is you have 6 lbs or better, its not a real gauge.

 

[MMeier]

Guess I'll have to bust out my manual gauge and put this "virtual" gauge thing to rest for once and for all.

 

[Matt400]

How will you do that?

 

[MMeier]

Hook it up to the fitting on top of the filter head and compare readings.

 

[Matt400]

When you do...



Use a hose that has a bypass in it and open up the bypass enough to bring your manual gauge down to 8 psi.

This should simulate a loose bleeding oil filter, oil pump bolts that have worked loose or a turbo line that broke.



I have not done this but. . based on the the OEM gauges circuit it should make no difference on the OEM gauges reading if you have 45 or 8 psi. Once the engine has 6 lbs only RPM and coolant temp move the OEM needle.

 

[rbattelle]

Hook it up to the fitting on top of the filter head and compare readings.

I do this every day. They "occassionally" read the similar values.



-Ryan

 

[Blu-meanie]

Install a Painless System from Genos then you will have all the power sources for this and the inevitable later mods.

 

[kcnizdodge]

Where did you mount the sending unit?

The cigarette lighter is a "keyed" power feed. Just curious- where did you mount your sender?

I mounted it to the top of the oil filter. There is a 1/8" npt plug there. I had to use a 45 degree brass fitting so it would clear the exhaust manifold but it works out perfectly.



Alan

 

[ThomasLawrence]

All my gauges (six of 'em - all Autometers) draw their power from the cigarette lighter circuit (red wire to cig. connector, center bezel), and all get their lighting from the diimer wire on the headlight switch (orange/white - changed to orange/black in '04+). All are grounded to the grounding lug on the right side of the knee blocker opening. Then the various signal wires (and boost tubing) runs through the grommet in the firewall to the various sensors (fuel pressure sending unit installed via a Tee fitting on the fuel supply [aftermarket fuel line - stockers can use a tapped banjo bolt on the injection pump], water temp. unit screwed in place of a 1/4" NPT plug in the head, oil pres. screwed into fitting on top of filter housing, boost screwed into 1/8" NPT hole tapped in side of intake horn, trans temp. installed in Mass Diesel replacement cooler line, and pyro installed in 1/8" NPT bung welded to downpipe [additional pyro tapped into exhaust manifold, feeding the TST PMCR]).



Additionally, with the exception of the boost gauge, and the pyrometer leads, all gauges are installed with in-line connectors (Molex-type, from the local Radio Shack). This allows easy disconnect in the event that the pillar, or steering pod, or dash pod has to be removed (it also made installation of the dash pod much easier). I have additional switches/etc. mounted on the center bezel, and those two use a multi-pin inline connector. Spend the couple of extra bucks and the extra 10 minutes to put these connectors in - it makes life a whole lot easier later on when you go to remove something.



-Tom



(And yeah, when driving the truck, the stock gauge will sit around 40psi the whole time, while the mechanical gauge reads about 25psi at idle, and quickly gets to 80psi by about 1500RPMs - at which point the relief valve opens to maintain 80psi. Factory gauges... worthless)

 

[nickleinonen]

i put a 18" grease gun hose to remote mount my oil pressure sending unit. 18-20 psi hot idling for me with 0w40 in the sump...