Adding an Electric Oil Pressure Gauge
Application: 1998 4Runner V6
Autometer Z-Series Electrical Gauge (#2634- includes electrical sender)
1/8" female to 3/8" male adapter
Lo-tek gauge pod (optional, but have a mounting option available)
Adjustable-head rachet with a variety of metric and SAE sockets
Various short and long rachet extensions
Crow's foot wrenches (rachet head)
18 gauge positive and negative wire
Soldering iron and solder
Heat shrink tubing and matches
PB Blaster (Liquid Wrench or Tabasco sauce)
P-Touch label maker
I am providing this write up for illustrative purposes
only. Perform at your own risk. Any mods (including this one) you perform
on your vehicle is your responsibility. Commercial use of this write up
may result in legal action.
- November 28, 2004
I discovered that I had a very small leak coming from the oil
pressure port. It was a major pain in the ass to diagnose and fix---mainly
because there is hardly any hand space in there. Of the major changes
to this writeup, I had to remove the sender from the 1/8"
female to 3/8" male adapter, teflon tape the threads on the adapter
and sender and *then* put it all back on. But there's an order you should
follow to make sure everything is leak proof. Read on.
I plan to install a Permacool oil filter relocator kit in the near future
and thus, I decided to add an aftermarket oil pressure gauge to monitor
the oil pressure. I installed this first because I wanted to understand
what the stock oil pressure is and then use the data to make sure that
the Permacool kit had no adverse effect on the oil pressure.
As is the case, this writeup borrows heavily from available resources
and previous installs. Special thanks goes out to Jsharp (Jim). Jim's
advice via email and PMs were invaluable to this mod as well as (and especially)
the Permacool oil filter relocator mod. Jim, much appreciated! Also, I
excellent gauge page as a reference as well.
Step 1: Prep Work
As always when doing electrical work, unhook your negative battery cable.
Next, remove the skid plate by removing the seven 12mm bolts. You may
need an extension to access all the bolts. After removing the skid plate,
spray a generous amount of PB Blaster onto the 8mm allen key plug as shown
in the picture below. After about 15 or 30 minutes, spray it again. What
I did was to spray it a few times and let it soak overnight.
the seven 12mm bolts (B) from the skid plate to remove
are looking at the oil filter and pump area as seen through the left
front wheelwell. Spray the rusted 8mm plug (A2) with PB Blaster. (A1)
is the plug to the oil pump discharge port and (S) is the stock low
oil pressure sender
also be a good time to unbolt some interior panels:
the four 10mm bolts
removing the lower panel, pop out piece (B) and unscrew four screws
securing door sill panel (C)
2: Removing the Extra Oil Port Plug
Take your adjustable head rachet wrench with a short adapter and a 8mm
allen key and remove the oil plug. The way I got it out was to manuever
the wrench up and around the front part of the oil pan. Buy using the
adjustable head wrench, you can move the shaft of the wrench to have enough
room to take off that plug.
space: Use an adjustable head rachet wrench with a short adapter and
a 8mm allen wrench key. Note: the plug is at the end of the 8mm key
you can see from this pic, I manuevered the wrench just right in front
of the oil pan and fitted the 8mm key onto the plug itself. As you
can also see, there is enough room from left to right to get some
a pic of the plug
3: Installing the Electric Oil Pressure Sender
Wind around two to three wraps of teflon tape around the 1/8" to
3/8" adapter and then hand screw it into the oil pressure port. Next,
use a rachet wrench with a crow's foot wrench (sorry guys, I forgot the
size) and tighten down this adapter. It is very important that you tighten
this down really good or else you will pull your hair out doing this over
again (like I did)!
Now take the sender and put some teflon tape on the sender threads and
then hand screw it into the adapter. Take your crow's foot wrench and
tighten the sender down into the adapter. This will be a bit more difficult
because of the lack of space that's been taken up by the adapter.
Next, starting from the middle of your dash area, run a length of 18 gauge
wire down between the A-pillar and the dash, through the interior firewall,
into the engine bay and down to the oil pressure sender. Cut, strip and
crimp a ring connector on this end.
At the other end of the wire, cut, strip and crimp a ring connector to
the end of the wire and slip that end onto the oil pressure sender's terminal.
Finally, re-orient the ring connector so it is in a good, non-stressed
position and then tighten it down.
I would highly recommend that you label this and all other wires so as
not to confuse them. That is why I recommend that you use a P-touch label
machine. Also when using teflon tape, start a thread or two down so as
not to risk clogging the flow of oil.
the electric oil pressure sender and the 1/8th to 3/8th adapter. Note
that the adapter is NOT included with the Autometer kit.
a pic of where to run the wire
Step 4: Hooking Up the Ignition, Ground, and Light Wires
For the ignition wire, run a wire down from the dash area to the ignition
harness. Attach a T-tap and tap the 12v ignition power wire. Cut, strip
and crimp the wire and attach a blade type connector to it and then connect
it to the T-tap. For my 98 4runner, the ignition wire was black with red.
Yours may be different, so definitely consult a wiring chart. I used the
wiring chart engine found on the12volt.com.
After doing this, cut, strip and crimp a ring connector to the other end
of the wire.
same procedure for the illumination wire. For the positive illumination
wire, you'll need to solder a wire to it and heat shrink the connection
point. From there, run that bulb wire from the dash and T-tap it to the
green wire that comes from the instrument cluster's dimmer knob/switch.
After doing this, cut, strip and crimp a ring connector to the other end
of the wire.
wire (I). T-tap (A) is for my hardwire Valentine 1 mod
wire (G) for the gauge's light. Ignore (W) and (D)
bulb's ground wire, solder/heat shrink the connection and run it to your
ground point. Crimp a ring connector to the other end. And lastly for
the gauge's ground wire, run it down from the dash area again and to your
ground point. Crimp ring connectors to both ends of this wire. Now secure
both ground wires to your ground point as shown in the picture below:
a bad soldering job, eh? :)
Step 5: Hooking the Gauge Up
Take your Lo-tek gauge pod and move it into position. Run all the wires
through the hole of your choice. You should have exactly 3 wires with
ring connectors and the bulb wire with two soldered positive and negative
wires. Hopefully you've taken my advice and labeled each wire. For the
three wires with ring connectors, loosely tighten them down onto the terminals
until final fitting. For the bulb wires, since you've already grounded
the ground wire and T-tapped the power wire, you don't need to worry about
these two wires.
you can see, I've run all the wires through one of the gauge pod holes
are all the terminal points: S is for the sender, (I) is for the Ignition,
(G) is for one of the two grounds, (+) is for the light bulb and (-)
is for the ground for the light bulb
Now is a good time to test it out before final fitting.
Reattach your negative battery cable and start your engine. You should see
the gauge needle shoot up to around 75 to 85 psi. If so, turn off your engine
and unhook the negative battery cable.
6: Final Steps
Tighten all of the screws down on the back of your gauge as well as re-checking
the two ground wires. It's also a good idea to cable tie those five wires
into a tight bundle. Do so and then insert/twist the gauge into the gauge
pod. Next put the bottom end of the gauge pod in between the existing
A-pillar and the dash. Realign it to your liking and then secure the gauge
pod with the supplied screws and screw covers. Also, the holes do not
line up with the stock grab handle holes. Not to mention, the screw sizes
are completely different. Thus, you will have to drill a pilot hole through
the existing plastic and metal. Of note, I could not screw in the bottom
screw because I did not have a right-angle adapter for my drill. Therefore
for the bottom hole, I used some double-sided tape to hold down the gauge
pod to the existing A-pillar for a more flush fit. Also, I hot glued the
screw cover on because it easily pops out.
final product pic:
it doesn't look like it, the gauge pod is about 99% close in color
to the stock color. Overall, I'm very pleased.
Readings and Opinions
On startup, the oil pressure shoots up to around 85psi. After a few minutes
of driving, it settles down to around 50psi. Driving on the streets and
on the freeway, it reads between 50psi and 60psi. However at idle after
driving a bit, the needle settles around 12 to 15psi.
Of the Autometer
gauge kit: I think this is kit provides an outstanding value. The kit
comes with the gauge, all the basic screws/hardware, and most importantly,
the electric sender. What it doesn't come with is the 1/8" to 3/8"
adapter. That only costs change, but this part was not available at Kragen
or Autozone and thus, I had to go to a specialty auto parts store.
Of the Lo-tek full A-pillar Gauge Pod: its a great looking piece of plastic!
The fit and finish is very good and the paint color is a *very* close
match. The only complaint I have is the plastic screw caps. They fall
out too easily and that's why I hot glued mine to the end of the screw.
Given the fact that these fall out so easily, it would be nice if Lo-tek
could include 2 more of these end caps as spares.
or feedback? Email me and I'll try to get back to you. If this article
helped you save time, money or just made things more convenient for
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