Why is it important for a gauges ground lead to be near the sending unit?

[triggz]

On all the Autometer instructions for their gauges, it specifies that the ground wire on the gauge should be a "good engine ground near the sender".

Why does it matter? Won't grounding it to a chassis ground or the neg battery terminal be just the same?


I'm redoing all of my accessory wiring and I noticed I only did it this way with my oil temp gauge, the rest of my gauges are grounded on a 0 gauge main ground wire to the battery that I have for the rest of my electronics (gauges/relays/remote start etc). They all seem to work just fine

 

[4.6andSlicks]

I have 4 years of education in electronics and have been repairing medical electronics for 17 years and theory would say both grounds are the same. You can verify this with a digital multimeter or ohm meter if there's a question. They're probably trying to do away with the chance you have a bad ground strap to the engine. If I was installing in my car, I would use the chasis ground.

 

[04DarkShadowGT]

I grounded my boost, elec fuel pressure, and wideband 02 all made by autometer to the screws attaching the fust box under the dash.

All works perfect for me. I did not even read the autometer instructions, I used the fnsweet.com how to.

 

[Kilgore Trout]

Personally, I would follow the manufacturer's suggestions...

 

[goshia]

On all the Autometer instructions for their gauges, it specifies that the ground wire on the gauge should be a "good engine ground near the sender".

Why does it matter? Won't grounding it to a chassis ground or the neg battery terminal be just the same?


I'm redoing all of my accessory wiring and I noticed I only did it this way with my oil temp gauge, the rest of my gauges are grounded on a 0 gauge main ground wire to the battery that I have for the rest of my electronics (gauges/relays/remote start etc). They all seem to work just fine

Gounding near the sender is a good practice. The reason for picking that location is to reduce the grounding efffects and stray capacitance of the wire that in return pick up RF noise that can effect the performance of the meter.

 

[the_rooster]

The longer the wire the more the resistance on the ground, though it is next to none they may not want to take a chance of a bad ground.