I picked up an Autometer coolant temp gauge for my car. According to Autometer, you have to use the supplied sending unit in order for this gauge to work. They insist that you cannot tap into the existing sending unit's wiring for their gauge to work.

My bros. is a licenced mechanic and feels this is a marketing gimic. All temp gauge sending units operate on the same principle. After all, it's just making a small needle move. The ECU even has its own temp sensor.

There's all these warnings with the gauge saying that if it's wired wrong, warranty is void, so I haven't tried. Anyway, has anyone ever tried just wiring their Autometer temp gauge to their stock sending unit?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by clsmooth &raquo;</TD></TR><TR><TD CLASS="quote">I picked up an Autometer coolant temp gauge for my car. According to Autometer, you have to use the supplied sending unit in order for this gauge to work. They insist that you cannot tap into the existing sending unit's wiring for their gauge to work.

My bros. is a licenced mechanic and feels this is a marketing gimic. All temp gauge sending units operate on the same principle. After all, it's just making a small needle move. The ECU even has its own temp sensor.</TD></TR></TABLE>

A gauge has to be properly calibrated to the sender.

I forgot exactly how a temperature sender works, but I dont think all senders from all manufacturers are the same.

EDIT: I believe it has something to do with different manufacturers and OEM car makers using different resistances in the temp senders.

 

Yea u cant use the OEM sender to operate the auto meter gauge. Like the other guy said, each gauge has to be calibrated to a certain sender. Make it very simple on yourself and buy a T type fitting (such as the one made by Autotechnic, i think thats their name...) and tap into the upper radiator hose. There is no need for drilling and tapping into the thermostat housing or anything like that, just tap into the existing rubber coolant hoses.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by clsmooth &raquo;</TD></TR><TR><TD CLASS="quote">
My bros. is a licenced mechanic and feels this is a marketing gimic. </TD></TR></TABLE>

Autometer doesn't make their money from selling senders. They're dirt cheap and Autometer gives them to you when you buy a gauge. Rather than make gauges that can only be used in certain cars based on the OEM sender, it's easier to make one gauge with one sender and scrap the OEM unit.

 

GOOD! Cause what a headache I had just trying to replace/install the sending unit
for the coolant temp gauge I want to use!

I borrowed some 'Easy-Out' bits from my bros., but instead of
unscrewing the reaminder of my stock sending unit, it put a small
crack in my head! Lovely...

I noticed with the bit still in the head, it didn't leak, but when I
squeezed a hose, it would. With my dad's help I picked up some taps
and some Permatex 'Cold Weld' compound.

We tapped what was left of the stock sending unit and screwed in a
bolt using the Cold Weld as a thread sealer. I then went to town
with that stuff around the bolt head! Stuff's great! Suppose to be
able to handle 3000 psi and 2500*F. Overkill, but well worth it.

We also re-tapped the bleeder screw and my sending unit now resides
there (2 fittings later). Turns out, the machinist who put my head
together used some sort of Loc-Tite or something. I don't know why,
when all you need is some Teflon tape.