And a question about grounds. Is it okay to splice the gauge ground wires into the ground wire going to the stereo head unit, since it's right there and so accesible, or should they each have their own ground? Meaning should each of the three ground wires coming from each of the three gauges be grounded in three distinct places on the chasis/frame/whatever? Sorry...I'm kind of green when it comes to electric. Actually, I'm kinda green when it comes to all of it, but I'm learning.
I don't personally think its a gas vs diesel thing...no reason at all for them to be different.
I also don't put too much stock in Duostylings web site...they have had the wrong picture of one of the sensors up for several years. ;-)
One ground for all the gauges is fine...for the best accuracy this common ground wire should be run thru the firewall and attached to the block. A double nut on one of the studs that holds the drivers side coolant flange on is a good spot...this is where the factory grounds the ECU on some gassers...so that it gets the most accurate sensor signals as well. A double nut on a valve cover stud would work too...another common factory location...but I find that to be more in the way...like when setting the timing.
Installed today. Pretty straightforward. Toughest part was feeding wires through firewall, but only because I was solo and had to do everything by feel.
Based on duostyling's suggestion, I ground the gauges at the negative post on the battery. Seems to be working well so far.
I spliced the power wires into the accesory power wire on my head unit. Works like a charm.
Readings so far have pressure at around 3 bar at idle and up around 5 bar at speed. Sound good?
---EDIT--- Volts are around 12 at idle and 13 or 14 at speed. Sounds good to me. It'll flick up and down a notch when I'm using a turn signal. Is this normal, or a bad ground? ---EDIT---
---EDIT--- Temp is around 90-100C at highway speed and around 80-85 around town, but it takes a good 15 minutes or so of steady driving to get up to temp ---EDIT---
The pressure gauge went into the head, and the stock pressure switch connected to the w/k terminal on the sender. Temp sender went into that extra port at the filter (black circle). Though it was longer than the one you all mentioned, it seemed to go in fine. It's smaller in person than in the pic. What would be a sign that it is inhibiting flow?
Now I just need to fab a custom housing to put them nice and neat into the cubby below the head unit.