theedge67

Anyone have an idea on how to make the stock gauges on the IUP functional? I still can't believe Ford put dummy gauges in a performance car. I really don't want to clutter up the inside of my 'Stang with aftermarket gauges, plus I really don't need to know the exact temp, or exact pressure. I'm just wanting to make the gauges read accurately...like they should have from the factory! Any ideas/suggestions??

Cleveland

they arent completely non functional, they just arent as accurate as the well informed would like them to be. The Mustang is more affordable because they arent VDO, Autometer or Ford Racing accurate. There isnt anything you can do with the stock gauges, go aftermarket or plug in a data logger for the info you want.

-Dan

theedge67

I'm pretty sure the oil press. and voltage meter gauges are basically non functional. They read the same as long as the engine has oil pressure, and has decent voltage. I know the temp. gauge is functional, but just not very accurate. The oil pressure and volt gauges only measure if you have oil pressure/volts. As long as there is some pressure/volts, the gauge reads the same. It's an on or off thing.

I'm wondering if a different sender unit attached to the stock gauges would make any difference. It seems to me that the gauge itself is dependent on the info it gets from the sender unit. Different sender unit=different gauge readings. Anybody have any ideas on this?

tkogt

we tested the oil pressure gauge at the shop the other day and if you were to put a real sending unit on it, it would work. but the high eng of the travel would be where it sits now (a little over 1/2 sweep ) even shorted to ground the gauge will not use the full sweep ?


jay

theedge67

So it sounds like it just needs a different sending unit for the gauges, but one that will move the needle the entire sweep of the gauge. Maybe a different sending unit made for a different gauge would work better??

tkogt

when you ground the wire the gauge should peg at full.

so im thinking the 2/3 IS full sweep for the oil pressure gauge.


jay

theedge67

So when you hooked up the different sending unit, did the gauge read different while the engine was at idle and then at higher rpms? I suppose different sending units would work similarly for the temp. and battery gauges??

theedge67

Anyone have an idea or part for a different oil pressure sender? Or if this will even work to make the stock gauges actually functional?

94tbird

cant do it. you would need a new sending unit, new wire, and something to translate the signal, aka aftermarket gauges. just ground out thestock one, install an autometer oil press gauge or whatever your trying to monitor.

MTAS

Exactly what I did. Grounding out the single wire for the stock OP "gauge" puts the needle right where it sits when hooked up - just to the right of center. The car's computer will not know the difference, and you won't lose any monitoring capability as long as you have a competent aftermarket gauge properly installed. If I recall correctly, 1995 was the last model year that the stock OP gauge (for a Mustant at least) could be modified via a resistor on the back of the gauge panel and a different sending unit.

dustindu4

can't replace the sending unit for coolant because there isn't one to begin with. That gauge is computed from the cylinder head temperature sensor and bascially will only tell you if you're overheating......which I have done twice so far. I don't recommend trying it.

The volt gauge only beeps at you if you lose power. Happened to me when my alternator died and the battery drained out. It just beeps, turns red then 10 seconds later your entire gauge cluster stops working until your battery dies to the point where the engine doesn't run anymore. I drove about 15 miles highway with no working gauges once.

oil pressure gauge only tells you if you have pressure or not. If you don't your cluster will read "OIL PRESSURE LOW". Happened to me too!

AWmustang

I'm not so sure about the voltage gauge being dummy. There is a light on my way to work that is incredibly long. If it hit it wrong i'll sit there for a couple minutes. So I will shut the engine off, but i leave the key in the "on" position so that the turnsignal continues to work. The voltage gauge dips with each "click" of the turn signal.

Would a dummy gauge register those dips in voltage everytime the turn signal bulbs light up?

theedge67

That is strange, mine will not move no matter what. I've left the radio on for several hours at fairly high volume, then got in and turned it to "on" and the gauge reads exactly where it does while running.

Centurion96

I have no experience on the S197 Mustang as mine won't be built until the first week of December. I am familiar with OBD-I and OBD-II as they apply to Broncos. Around 1989 or 1990 Ford changed the oil pressure sending unit to a switch rather than an analog pressure sending unit. You will have to check thread counts and size on the switch unit and try and find a match among previous years for a true pressure sending unit. The Bronco and truck guys would then put a load resistor in the circuit to get proper sweep on the gauge. I don't have my manuals with me so I can't remember off hand whether it was the temp circuit or the oil pressure circuit on my 351 that had two sensors, one for OBD-II and one for the gauge.

I'm going back 40 years to my avionics training so I may be a bit rusty on my theory. The gauges are D'Arsonval movement galvanometers, you put a voltage thru them and a coil will react to a permenant magnet to position the dial. Automobile maufacturers save money by feeding only one wire to a sending unit and it provides ground to complete a circuit. So an open sending unit will cause the gauge to zero itself. With an analog type sending unit that provides a decrease in resistance under pressure or tempurature, it will cause the needle of the movement to change postion. Now the gauge itself will have some load built into it because when the switch type sending unit shorts then the gauge goes to a normal pressure position without burning up wires and components. If you put a resistor in parallel to the gauge you can vary the resistance of the gauge thus allowing it to work with an analog sending unit. You will have to experiment with different sized resistors to see what works with the sending unit you purchase. You will also need to research sending units prior to 1990 for a fit. Depending on where the oil pressure sending switch is located, you may need to get a sending unit extension from Ford as the analog type units are wider than the switch units (at least they were on the 302s and 351s). Aftermarket gauge manufacturers will be another source for sending units.

Hope this helps
BB

Semper Fi