it still needs to somehow get the reading from the engine, either

its a vacuum hose, or a electrical sender, otherwise how would the

gauge work.

So the sender plugs in separate from those 4 wires? do you have a pic

What they are driving at is that according to the wiring setup listed above, there are no wires connected to a sending unit so how is the gauge getting its information? Where is it reading the boost from...according to this?

I have everything except for the actual instructions from HKS. I have two of these gauges, one is brand new with everything but the box unopened and a used one. Both are missing instructions which sucked until now.

One of the wires must be for a grounded sender, like an oil sender.

i dunno either but my greddy would flip out without it https://www.nopistons.com/forums/pub...1047683561.gif

ya greddy electronics have constant 12V, not sure why. Rob, i think the HKS has two harness, one for power, and another that goes to sender unit in car.

if it has peak/hold I can see it needing it for that

correct. The sending unit connects to the back of the gauge using its own harness. The gauge itself has another harness for power. The sending unit gets its power from the gauge. Something like this...



--POWER--> [GAUGE]--POWER-->(SENDING UNIT)

Hi there



Thanks a lot for that information. I was searching for hours.. Can you forward me the pdf? I've got the following EGT-gauge:

http://alonso.ch/galerie/bilder/uploads/115.jpg



The wiring for the power and the sensor is allright now. But there are any other wires (blue and so on). I think they must be the output for the warn, or what do you think?