Before the KMJ I ran a J2Fab with this same wire upgrade and it made 14+ at idle from day one. So I don't think it's the wire set up.
It wasn't the alternator
- Thread starter 01yellercobra
- Start date
I drove the car today and I saw it dipped down to 12.7/12.8 volts after the car was warm and I was at a light and the fan kicked on. As soon as I tapped the gas it shot back up to 13.4. Cruising around it was 13.8 once hot. I’m gonna continue to monitor it but I’m still breaking in the clutch with the motor on a break in tune and I haven’t had much time to drive it, and the weather here is still crappy at times.
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I would check voltage at the battery and compare against the gauge, the obd2 port frequently reads a few tenths less than actual. I wouldn’t concerned about 13ish at hot idle
The fan is a big draw, it will pull the voltage down, sounds like you have the issue beat.
Mid 13’s is perfect. Congrats
Mid 13’s is perfect. Congrats
Yeah I’m going off my aeroforce gauge. I’m going to check all the connections again. I noticed the connection to fuse box near the battery was really loose last week and I tightened that up.
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Cruising I would see mid 14's. That was with a/c and stereo going. You're probably not horrible, but I'd still keep an eye on it like you said.
Yeah I’m going to monitor it going forward. I initially thought maybe the 130amp alt on the car now might be almost not enough. I’ll keep an eye on it when I drive it and see.
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To close this out... if I had found that fuse before I swapped alternators I would have saved a lot of time. Turns out the new regulator I installed in the J2Fab is junk. I put the KMJ back in and all works again.
Having a similar issue on my Term. Jumped the car let it run for about 20 mins. Took off the jump cables and car couldn’t stay on. Noticed my trunk light does not turn off when I close the trunk and could be draining the battery. Disconnected the wiring and tried again. This time the car ran for a bit. Voltage on battery maintained 13-14v but dropped to 11.6 after I turned it off. Checked the voltage on the battery a few minutes after and noticed the battery went up to 11.98v. Would anyone agree it’s the alternator or do you think I have another problem here?
Sounds like your battery is bad. 13-14vdc means the alternator is working. Dropping below 12 when the car is off is bad. You could try a deep charge. But there's a chance the trunk light staying on killed it.
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Sorry, forgot to add, the battery was replaced a few weeks ago. But I did let it sit for almost 2 weeks without driving it. Perhaps the trunk light is the reason for this. But, I’m going to jump it again some time during the week and see if I can stay running. If I can, I should be able to get a better idea after testing voltage again on the battery. Want to know for sure before I go and buy another battery.
Never charge a dead battery with the alternator. It's bad for both components. Buy a proper battery charger and do a slow overnight trickle charge. If the problem persists, take the car in to get the alternator and battery load tested. A lot of parts stores will do it for free.
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