420A Autometer water temp install. which wire? which fittings?

[jayson427]

So I have looked and looked every where but no direct answer to the 420a that I could find. I just bought an Autometer oil/water/boost and glow shift EGT. I'm only trying to do the water and oil for now.

I am lost on the water tho, I want to run my factory sensor and splice into that and run the gauge. I don't know if that is the right way to do it or which wires on the t-stat housing are the signal wire to run to the gauge. If I splice into the signal and run that plus power and ground to it, that will work correct? I am just unsure. Both are electrical also.

Now for the oil. I can just run this off of the oil pressure switch and T into it right? Any links or videos would be greatly appreciated. I bought these lightly used so it came with no directions.

 

[VelocitàPaola]

So I have looked and looked every where but no direct answer to the 420a that I could find. I just bought an Autometer oil/water/boost and glow shift EGT. I'm only trying to do the water and oil for now.

I am lost on the water tho, I want to run my factory sensor and splice into that and run the gauge. I don't know if that is the right way to do it or which wires on the t-stat housing are the signal wire to run to the gauge. If I splice into the signal and run that plus power and ground to it, that will work correct? I am just unsure. Both are electrical also.

Now for the oil. I can just run this off of the oil pressure switch and T into it right? Any links or videos would be greatly appreciated. I bought these lightly used so it came with no directions.

I doubt you can use the same coolant temperature sensor for both the stock PCM and Autometer gauge. You can't use the same sensor for the stock PCM and a MegaSquirt ECU because the stock PCM switches bias sensors. MegaSquirt systems have no way of knowing what bias resistor the stock PCM is using, so it's unlikely your gauge would either.

You can use a T fitting to install your new oil pressure sender. Just be sure you don't mix and match your fittings: SAE is different from -AN. The threads are compatible, but an SAE fitting won't seal against an -AN fitting.

I used a T fitting to keep the stock oil pressure sending unit at first, but I found it was easier to ditch it in the long run. The fewer fittings, the fewer leaks. There's nothing the gauge can't tell you that the OPSU will.

 

[jayson427]

Yeah apparently I didn't get the sending unit for the water so that could be helpful to have . That's why I was so lost with it.

Yeah I know what you mean they read on different scales right?

 

[VelocitàPaola]

Yeah apparently I didn't get the sending unit for the water so that could be helpful to have . That's why I was so lost with it.

Yeah I know what you mean they read on different scales right?

More or less. Think of it this way: the gauge reads on one scale, but the stock PCM reads on two different scales. The gauge might be able to be calibrated to read one of the PCM's scales, but not both.

 

[JDT]

I'm going to install an autometer oil pressure sender later today, I hope the oil sensor port wont leak oil with the car jacked up.


Update** Just tried to pull off the stock sensor but there's no space under there. I'm wondering how everyone else pulls it out, I can barely fit my arms through the gaps. I'm thinking of trying to work on it from above the car but there's a black box in the way, not sure what its purpose is.

 

[VelocitàPaola]

Update** Just tried to pull off the stock sensor but there's no space under there. I'm wondering how everyone else pulls it out, I can barely fit my arms through the gaps. I'm thinking of trying to work on it from above the car but there's a black box in the way, not sure what its purpose is.

It's been a while since I last dealt with it, but I'm pretty sure I removed the sender from above. Also, having the correct tool is basically required; a 1-1/16" deep well socket. MAC and Snap-On sell purpose-made tools too.

 

[JDT]

Ill check my local auto parts store tomorrow. What's special about the socket, is it much deeper or shaped differently on the inside...etc?

So after some research I've found the vacuum box is for cruise control... well, guess I won't be needing that.

 

[talonalex92]

The socket is special because its "deep" and doesn't have flat edges. They are rounded. Look up a Lisle brand 13250. Its what I have, works great.

 

[VelocitàPaola]

This is what I have. It's probably made by Lisle.

Mac Tools Online Store - Oil Pressure Switch Socket