Auto Meter Ultra Lite Electrical Oil Pressure and Water Temperature Gauge Install
2004 Ford Mustang GT 4.6L V8 (all 99-04 GT's?)

I couldn't find much help on the web where exactly to install the sending units. These instructions allow you to retain your stock gauges as well. Just thought I would put this together to help someone out in the future.

Fittings for oil pressure:
1.) 1/4” male to 1/4” female OR 1/4” male to 1/8” female 90 degree elbow pipe adapter from hardware store
2.) If you choose the 1/4” to 1/4” you’ll need the 1/4” to 1/8” pipe adapter supplied with your auto meter gauge otherwise the sending unit should attach directly to the 1/8” female side of the elbow.

No special fittings needed for the water temperature. You’ll use the supplied fittings from auto meter.


Tools Needed:
1.) 8mm hex socket, u joint, extension and ratchet
2.) Wire cutters/strippers
3.) Soldering iron (optional)
4.) Funnel and pan for small amount of oil and coolant that will spill out when removing the plugs
5.) Other basic hand tools…wrenches etc.
6.) 18 gauge wire…I bought 3 colors so I know what wire is what. For the gauge I used black for ground, red for power and green for signal. I reused the black for the gauge light ground and red for the light’s power.
7.) Heat shrink wrap and electrical tape to keep the wires together and clean.
8.) A soldering iron will work best to connect the wires but it is not necessary. I used wire quick connects and crimped them. You can also get quick connects for the gauges as they have prongs to attach a connector to.
9.) (2) “add a fuse” (mini) circuits from auto zone or auto parts store. If these do not come with fuses you’ll need (2) #5 mini fuses as well.
10.) Zip ties and possibly wire loom if you want a clean install so you don’t see the wires in the engine bay.
11.) Teflon tape


Steps for oil pressure:
1.) Remove the oil plug where you’ll install your auto meter pressure sending unit. This plug is directly under the oil filter and is an 8mm hex pattern. A small amount of oil will come out so be prepared.
2.) Put 1 layer of Teflon tape on the male end of your 90 degree elbow and install into plug location. The sending unit will point towards the drivers side fog light once installed so you’ll need to make sure the female end of the elbow is in that general direction to clear the power steering rack. Make sure it’s tight enough…I had mine pointing the correct way but quickly realized I could still get a full turn on the elbow into the plug location. I suggest hand tightening and then using a wrench to turn and tighten the remainder.
3.) If you chose the 1/4” to 1/4’ inch elbow you’ll need to put Teflon tape on the auto meter 1/4” to 1/8” adapter and the sending unit. Otherwise just the sending unit. Install the auto meter adapter onto the sending unit then into the elbow. Use a wrench to make sure all is tight.

Steps for water temperature:
1.) Assure the car is cool! Remove the coolant plug where you’ll install your auto meter temperature sending unit. This plug is located on the driver’s side of the block right above your oil drain plug. If you look up by your oil drain plug you’ll see an 8mm hex patter plug in the block. My arm was drenched in coolant when pulling this plug, be prepared! I also drained my coolant before starting this project as I was going to change it anyways.
2.) I used the adapter that came with my auto meter gauge. I believe it’s a ¼” adapter fitting. Apply a single layer of Teflon tape to the temperature sending unit threads and insert into the adapter. Then apply a single layer of Teflon tape to the adapter and hand tighten into coolant plug.
3.) I used a deep socket to firmly tighten to the block. You may be able to tighten adapter to block first then install sending unit. Either way you do it just assure it is all tight.

Steps for wiring:
I ran the power and ground wires together behind the gauge pod so I didn’t have tons of wires.

1.) Lets start off with ground. Run 4 black wires together first. One for each gauge ground and one for each back light ground. Then run your single ground wire to a good ground location. I used a stock bolt on the frame behind the drivers side kick panel.
2.) Next is the signal wires. Obviously you don’t run these together you need a signal for each gauge. You’ll need a way to determine what signal wire is for what sending unit. I marked my water wire with blue electrical tape. Run both signal wires through the firewall from the gauge. I used the stock firewall grommet by just pushing it aside and wrapping the wire with electrical tape. You can choose to drill a new hole or poke a hole in the stock firewall grommet. Once you have the wire in the engine bay wrap it with wire loom if you are using it. I ran the wire loom along side of other wire loom before dropping it down by the oil pressure sending unit. Use zip ties as necessary. Once you’re close to the oil pressure sending unit you can attach the wire. To get to the water temp sending unit I followed the clutch cable through the k-member. I fed the wire loom through the k-member with a hanger and zip tied where necessary. Once you’re under the water temp sending unit send the wire up and attach. Just assure you have some space between the exhaust so it doesn’t melt your wire!
3.) Last is the power. Here you’ll run the 2 red wires for the oil and water gauge power together and then the 2 red wires for the oil and water back light power. After you run these together behind the gauge pod you’ll have 2 red wires to route to the fuse box underneath the dash. Once your wires have been routed you’ll connect both to separate “add a fuse” circuits. For the gauge power you’ll remove the fuse in spot #37 (a #5 fuse) and add 2 #5 fuses to your “add a fuse” circuit and install into slot #37. For the back light on the gauge you’ll remove the fuse from spot #23 (a #15 fuse) and add 1 #15 fuse and 1 #5 fuse to your “add a fuse” circuit and install into the #23 slot. Assure you put the #15 fuse in the correct location (should be closest to the prongs of the circuit). This will allow the back light to come on with the light switch and also will allow the lights to dim along with your stock gauges. To see a reference to what slots the fuses belong to click here for the fuse diagram (Page 161-163) https://web.msslib.dealerconnection....000c5880331a9a


That’s it, you’re finished. The only issue I had was with my water temp gauge being pegged. Troubleshooting led back to discover a bad ground connection.


Here are some pics:

Here is where I ran the wire through the stock firewall grommet location



Here you'll see the clean wire loom dropping down towards the oil filter



Here is the wire connected to the oil pressure sending unit and the wire loom zip tied to the clutch cable which I followed back through the k-member to get to the water temp sending unit



Oil pressure sending unit





Wire loom zip tied and following the clutch cable through the k-member toward the water temp sending unit



Water temp sending unit





The add a fuse circuit for slot #23 (#15 fuse & #5 fuse)



The add a fuse circuit for slot #37 (2 #5 fuses)



The add a fuse circuits installed...you won't be able to put the fuse cover back on



Finished product (the auto meter ultra lite's match the simco silver series cluster except the needles which are orange on the auto meter's). My third gauge is a digital shift system (shift light) from auto meter. My buddy did this install for me as he has done a few shift lights. He used directions from raptors web site.

 

Nice write up man and the gauges look good. Could you take a night shot with them on? The boost gauge I bought is the same style and I wanted to see what it looks like at night.

 

Nice write up!

Though you should of gone through the firewall grommet and not around it. Otherwise the wires are gonna chafe and your gonna have electrical problems later on.

 

Thanks guys...I agree that going around the side of the stock grommet wasn't the best idea. I'll probably drill a new hole for another grommet location at some point.

As requested here are a couple night pics. I've got the auto meter LED conversion bulbs so the lighting is different if you use the bulb that comes with the gauge. The intensity of the LED bulbs matches the simco cluster better. Also in the pics it looks hard to read the pointers but the pics didn't turn out the best without the flash.

 

Thanks man. So with the LEDs, you can still see the gauge and needle just fine? I may have to get the blue LEDs to match my gauges and cd player.

 

yeah...it's a little dark but you can read them just fine. In the pictures I had the dimmer on the lowest setting as well.