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New install offset voltage spike question
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qsiguy Offline
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Post: #1
New install offset voltage spike question
Installed my EFIE this weekend and all went fine and the unit is working as expected. I did experience one small "anomaly", I'll call it, during the install. I installed the unit, ran it for about 10-20 minutes or so. The offset was relatively stable at about .23 volts. I decided to change the ground wire connection and after reconnection of the new ground I started the motor and the offset spiked up to about 1.4 volts for about 30 seconds or so. The engine was running rough during that time, no CEL, and it came back down and settled back on ~.23 volts. I believe I left the key on and the unit was switched on when I pulled the ground. When I reconnected the ground the unit would have been powered up by that. All I can guess is that the unit may have built up charge while I had power applied and the ground removed.

Any thoughts on this scenario. Obviously, I should have turned off the power switch as well as the ignition before doing this mod. Shy Dumb move for a "seasoned veteran installer". Go ahead and let me have it, I deserve it!

Thought I'd share the experience.

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02-18-2008 10:52 AM
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mike Offline
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Post: #2
RE: New install offset voltage spike question
Wow, you got me. If there's no ground, the relay should have the EFIE switched completely out of circuit. My guess is some combination of power, ground, relay in/out somehow let the capacitor get charged up way more than normal. It would take a while for it to come back down as it's a 470 uF output capacitor that holds the EFIE's voltage steady, and delays it's voltage ramp up.

Let me know if anything else similar comes up. But I think it was just a weird circumstance.

I'd "let you have it", if I hadn't missed the variable regulator in you MAP/MAF design. Big Grin

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(This post was last modified: 03-27-2008 02:43 AM by mike.)
02-18-2008 12:28 PM
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