i installed an electrical boost and afr gauge a while back and they worked alright for a few weeks. then after a while, the afr wasnt reading correctly and the boost would short out after a while of use and stop working. i attributed this to a bad ground point, as i was tapped into the ignition fuse for power but i ran the ground simply to a large metal bracket behind the cluster.

anyway, i rewired the ground recently to the accessory ground, and the gauges worked at first for a few days, then they didnt again. the weird part is that when i tried to start my car after i hooked them up originally, it wouldnt start until i unhooked the guages. i reconnected them and it starts fine most of the time. however, i tried starting my car yesterday and it would not start, and it still would not start with a jump. i thought it may be the battery (original one getting old on a 2000) but now i think it may be the wiring somehow. i havent gotten around to disconnecting the gauges and trying it.

the battery when the car isnt running reads around 14-14.5 volts so it seems ok. after starting it reads 12.5 or so, so it's probably not the battery.

* my first question is what points are commonly used to hook up said gauges, if not the points i used?

* and my second question is is it possible that the connection points i used are shorting out the ignition, and how? the gauges should be a relatively high resistance so as to prevent a short there, but i dunno.

sorry for the long post. just havta make sure all the infos there.

 

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cmon cmon

 

Are you doing the ignition trick where you lift the fuse and then stick the wire under it and push it down? If so dont do that. I would get a 14 to 16 gauge wire and a 10amp fuse holder from Autozone, or even radio shack and run that straight from the batt with the fuse and tap the gauges off of that.

If your not comfortable with that then tap a line, for both gauges, into the ignition wire of the radio.

For the ground put it to the frame.

 

i used a fuse tap from the ignition fuse with a protective fuse on the gauge line (autometers recommended fuse, either 3 or 5 amps), so basically, yea... but the reason i did that is because the boost gauge requires a power source that doesnt get cut when the car is being started. that was the only one i could find.

secondly, i was considering tapping the radio, but i want something that goes off when the key is removed. if i tap the radio or run it straight from the battery, its going to leak current (aka keep the gauges on) when the car isnt on, and thats not what i want.

for the ground, yea, a reliable ground is key, and i think tapping the accessory ground is plenty sufficient.

any other 12v lines to tap that stay on when the car is being started? anybody with any electrical diagrams or info?

 

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