Aftermarket Gauge Wiring Question

[Hemlock]

I am finally biting the bullet and changing to external gauges for water temp and oil pressure. Too much of a guessing game using the stock ones with their "normal" reading

I know motors and car stereos but I am clueless when it comes to most other car wiring things so if this question is a no brainer please cut me some slack.

Is it possible for me to hook up both the factory gauge and the new gauge to the same new sensor without it effecting the reading of the new gauge? My OCD is going off at the thought of the gauges in the dash not functioning but I don't want to hook them up if it will screw up the new gauges reading.

Any help is much appreciated,

Robert

[BMW Rider]

I don't know if you could find aftermarket gauges that will work with the stock sender units, usually you have to replace the sender with the correct one for the gauge. If you want to keep the original gauge functional, then just add a second sender for the new gauge.

[Hemlock]

I am planning on using the new senders that came with the new gauges but unfortunately there is limited places you can hook up these senders. There is no room to install the 4 senders. This is why I wanted to know if I could hook up both water/oil gauges to the same new senders. IE: 2 water gauges on the same water temp sensor and 2 oil gauges on the same oil pressure sensor.

Robert

[87gtVIC]

Some t stat housings have the boss for drill and tapping to add a secondary sending unit. Look into that so you can leave the stock one right above the number 5 cylinder on the lower intake.

Gonna have to purchase a tee fitting for the oil pressure extension bar. Will enable you to fit the stock bell sending unit and the aftermarket one. Will have to get creative in fitting them both though as space is limited down there.

[erratic50]

I have used pipe fittings with T's on cars with idiot lights before when hooking up gauges. This way there is a gauge and a light.

There are cleaner better looking ways to do it but it works.

[mikestang63]

most aftermarket gauges require their own sending units .
For the water temp gauge you can get a thermostat housing with a bung fitting in it
For the oil pressure sending unit, you can tap a 1/4" hole in the sending unit log that comes out of the block to the stock sending unit, or just buy one of these

http://www.ebay.com/itm/Viair-1-4-M-...item3d3622f86c


I'm about to do the exact same thing on my 86. tired of the stock gauges reading fine, then high. Replaced the sending units, gauges and IVR, even added additional ground cables from the block to the chassis. I am going with a set of Autometer electric gauges and install them in this pod to keep it somewhat stock looking,

https://lmr.com/item/LRS-13594B/Must...auge-Pod-79-86

[mcfairmont]

Personally I much prefer mechanical gauges. As mentioned, its no big deal to drill and tap another hole in the hex shaped extension that the factory oil pressure sender is threaded into, so the old & new sender, or the fittings for a new mechanical gauge can co exist. Coolant temp is a bit tougher, I would prefer to have any senders or sending unit mounted behind the thermostat.

[gr79]

Both of the wheels here have 2.3L engines, but notes may apply to others.
Any failures here and you may have to walk, then fix, plus clean up the big mess.

Should you opt to use tee fittings for a sender:
Do not use brass extension pipes. Too soft.
Engine vibration can crack them, snapping off at the thinner threaded area sticking out of the block.
Use regular iron pipe or factory parts.

Adding mech temp gauge:
A Motorcraft KT-82 tee works great in the heater hose for mechanical temp senders.
My 93 Ranger has that tee from factory, for a temp sensor, in one heater hose.

Discovered the KT-82 had the correct thread for the mechanical temp 'cable'.
Added a second KT-82. Used a short section of hose, in the middle of the tees, to connect them..
No hose cutting was needed. Was the only spot avail for tandem tees.
Pulled off one end of heater hose from oem tee, installed that to 2nd tee, then added short section of hose to complete.
Being in the heater hose, the gauge reads coolant temp from startup thru warmup.

The KT-82 tees aren't cheap, eventually rust, but serve a vital function and provide an easy solution.
Using a spare Prestone flush tee was considered impractical.

Have bought a newer style 2.3 thermostat housing featuring a threaded bung on the heater hose pipe.
Going to replace the rusty one soon, but not going to use the tap just yet.
The mechanical one will go there, with a new hose tee for the factory temp sensor.
Dunno if moving the factory sensor from the tee to the t-housing will affect its calibration.

Adding mech oil gauge:
No additional sender needed. Direct connection to engine.
Short iron pipe and brass tee.
Teed the Ranger's stock oil sender with an Autometer mech via braided hose. 2 oil gauges.
The Autometer mech is way more responsive than the stock gauge.
A short brass extension pipe lasted 1 year. In 1999, sheared off right at the engine block.
Lucky. Bad- it broke. Good- was parked on drive at home.
The added weight of the brass tee hanging out there was too much for the pipe threads.
Getting all of the threaded brass pipe broken in the block out intact was no fun.
Iron pipe and a braided hose to the gauge was installed, in place of the nylon tubing and compression fittings.

The latest mods here were done 10+ years ago and have been/are working out fine.

[mikestang63]

So i installed the automter phantom volt and water temp gauges in the LMR gage pod. Revomved the center console to make it easier to work on it on the bench.
Tapped into the information center key on and light wiring, and used the E brake bolts as a ground.

Fixed the dang erratic stock temp gauge and now I have a real volt gauge intead of the stupid ammmeter.
It matches the white face dash i bought off another member.

[Hemlock]

Both the gauges I installed are electronic. I was putting the gauges in a pillar pod and didn't want to run the risk of a leak or messing with the limited space in the pod.

Thank you for the responses,
Robert