Gauge wiring help

[ChopstickHero]

OK, maybe somebody can help me.

I started to install my gauges today... then hit a snag when I was about to finish. My oil pressure and oil temperature gauges light up fine (wired to dimmer switch). I'm pretty sure the switched ignition is wired up correctly, it's wired to the same wire as my Greddy turbo timer (and my tt works fine). I put in a 10amp fuse inline to the gauges (read somewhere this is a safety thing). I grounded the gauges in the engine bay near the driver side strut tower (there's a set of grounds there). Hooked up my sender wires (that was prob easiest thing) to the oil pressure and oil temp sending units. I used an oil sandwich plate that fit perfectly to hold the sending units.

The end result: started car and the gauges have no movement. I even warmed up the car till temp gauge was in the middle. Still no movement.

My questions: Am I supposed to ground the wires from each gauge separately? I currently have them consolidated into one wire, so it's easier to ground. And do i have to ground that near the sending unit? They're currently grounded near the driver side strut tower.

Thanks

 

[Maxx Mazda]

I didn't use seperate grounds for mine either, don't worry.

So, I'm assuming they're autometer, when the key is off they should read below the bottom tick. When you turn the key on, (even when cold) the needles should twitch up to the first line and stay there. Do they do that?

Check your fuse.

 

[ChopstickHero]

they're Stewart Warner... but yeah, essentially the same thing. They don't twitch, they don't move.

I replaced the 10amp fuse and still no luck. everything should be wired correctly. i've wired my other gauges similarly and they are working fine.... hmmm.....

 

[Maxx Mazda]

What did you tap into for the ignition power? Blue wire in the steering column is the best one.

 

[ChopstickHero]

What did you tap into for the ignition power? Blue wire in the steering column is the best one.

yep, that's what i tapped

 

[SeR_Cyclops]

i would go back and check all connections with a light tester.

 

[ChopstickHero]

i would go back and check all connections with a light tester.

yeah, i think that's what i'm gonna do! it's pissin me off that it won't work... it's supposed to be easy. haha

 

[AusOrion]

Yeah, don't need separate grounds or grounds near the sending units. If your ignition wiring is fine, might want to check the sending units. Oil temp changes very slowly (way slower than water temp) so check the oil pressure sender with a voltmeter as it will change as soon as the engine starts.

 

[SeR_Cyclops]

true dat.

 

[ChopstickHero]

one thing i could think of is that i'm using an oil sandwich plate. there is some foam/rubber on one side to seal it against the oil filter outlet. could it be that the sending units aren't grounding properly due to that seal? like it's not a metal to metal contact which would make it ground properly. also, i used some thread sealant on the sending units, but i didn't use that much, so i assume it is grounded properly.

 

[ForceFed]

SImple solution to that is to provide a temporary ground to the Sending unit.
I would have to say thats not it though..The ring has to be connected to the block where it screws on..Regardless of the rubber O-ring seal.

Just to test..Wrap a wire around the metal base of the Sending unit and attach it or wrap it to a grounding point and try it then.
I doubt you will see a change..but Its worth a shot.

I am very good at wiring and troubleshooting...What wires do you have on the gauges..and where are they hooked.
LMK and I will try to help you out.

 

[mx-p5]

Matt, what ga. wire do you suggest to run if the gauges ordered don't have long enough wiring?

I'll be installing Prosport water temp, oil temp, and oil pressure gauges. Also will be using the sandwich plate for the oil gauges.