Temperature Gauges
and Autometer Gauge Bezel

Updated 10/18/01

Installing the Autometer Gauge Bezel was so simple that I am not going to go over the steps involved in any detail. The stock piece has two screws at the top, and two plugs that snap into place at the bottom.

Again, The installation of the actual gauges was simple as well. I started by taking all of the wires of the gauge I was installing on the passengers side of the bezel, and tapped them into the wires for the gauge on the drivers side. Simple. Then, I took the wires for the drivers side gauge, and tapped them into the wires for my GReddy EGT. REALLY simple.

The tricky part was the installation of the temperature senders for the two gauges. Let's start with the water temp probe.

GReddy wells a 34mm temp probe housing. BUY IT. It only ran me around 30$ and the amount of time it saved was amazing. To install the housing, cut the upper radiator hose near its center. You want to use the upper hose because the coolant mixture is going to travel out of the engine through this hose. This will give you the best representation of the engine temps. If you use the lower radiator hose, you will be seeing the temperature of the coolant mixture as it leaves the radiator.

The picture below illustrates where to cut the hose.

I found it easiest to cut the hose by flattening it and then using tin snips. Make one cut through the hose and then additional cuts to trim material off of each end until there is enough room for the housing. Do not make large cuts or you might cut too much off.

Before inserting the probe, wrap the threads with silicone pipe tape. This will help the threads seal better and prevent leaking. Below is a picture of the probe with the threads wrapped.

That is it for the water temp gauge. For the oil temp probe, things were a bit more tricky. In fact, I am still leaking oil.. nothing that a little RTV will not fix, though.

There are a few methods of installing an oil temperature plug. One person said they would remove the oil pan and then weld a plug onto it that the probe would be screwed into. Would work perfectly, however I did not want the down time associated with removing the oil pan.

Another option would be to have the stock drain plug drilled and tapped for a probe. The local machine shop said they would charge 40$ for this, and it might not work anyways as the walls of the plug would be too thin afterwards.

Someone mentioned to me that VDO sells a drain plug that works on our cars, and comes tapped for a temp probe. I checked around and could not find one, and either way, I would not want to wait another 2 weeks for someone to ship one to me.

While browsing the aisles at Pep Boys, I found a M14x1.50 oversized piggy-back drain plug. These plugs come tapped already, although they do not mention what size the thread is. Well, it ends up that the GReddy temp probe fit perfectly!

One problem, is that this is an "oversized" drain plug. This means that the threads are purposfully too large. The idea is that if your oil pan is stripped, you can use this plug to basically re-tap your oil pan. What it ended up doing is strip the threads out and not go in straight. I ended up taking a dremel to the drain plug and cutting it down to the proper size, running it through a die to re-do the threads. After that, I ran a tap through the oil pan and cleaned those threads up as well.

Below is a picture of the modified drain plug with the temp probe installed.

Now I just need to glop on enough RTV to seal off the threads and I will be all set!

Driving Notes:

Water Temp
I have been driving with the water temp gauge for about a week now and have noticed that operating temperatures tend to stay between 85c and 95c. On hot days in stop and go traffic, I have seen as high as 100c. By the end of this weekend I should have a front mounted intercooler installed. We will wait and see what that does to my water temperatures.

Oil Temp
Oil temps seem to stay a little bit higher than the water temperatures do. Generally between 90c and 100c. I have seen up to 105c at the highest. Once the FMIC is installed, I will be installing a GReddy oil cooler as well. Check back once that installation is finished and we will see how much of an affect it has on operating temps.

The Autometer bezel has since been removed. The finish was not quite right, the gauges were a little too deep.. it just wasn't perfect. So I had a friend offer to make a din panel for gauges below the stereo. There is room for three gauges there. Currently the third spot is filled with my old Cyberdybe a/f gauge as a place holder. Most likely I will end up with a fuel pressure gauge there sometime in the future. The picture looks bad due to the flash .. I will try to get a better picture up at somepoint, but you get the general idea.