Losing Power
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Losing Power
Ive been chasing this dang electrical gremlin for awhile now. Once I drive the car and get it warmed up, shut the car off, it will not start again (turns over slow like the battery drained). Let it sit for a hour it starts right up. Now another issue I'm having is when the fans kick on or I close/open my soft top it shuts off my car. Ive already bought 2 different new OEM Honda replacement batteries. If I come back to my shop and shut the car off, then replace battery with my other known good battery the car will start. So I'm certain it has to do with a battery heat soak/drain. My battery is relocated to the trunk with high quality battery cable. Could the new ground location (the rear strut bar bolts) be the issue? Thats kinda what Ive narrowed it down too. Thanks in advance! Pic for boring factor lol
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Ive been chasing this dang electrical gremlin for awhile now. Once I drive the car and get it warmed up, shut the car off, it will not start again (turns over slow like the battery drained). Let it sit for a hour it starts right up. Now another issue I'm having is when the fans kick on or I close/open my soft top it shuts off my car. Ive already bought 2 different new OEM Honda replacement batteries. If I come back to my shop and shut the car off, then replace battery with my other known good battery the car will start. So I'm certain it has to do with a battery heat soak/drain. My battery is relocated to the trunk with high quality battery cable. Could the new ground location (the rear strut bar bolts) be the issue? Thats kinda what Ive narrowed it down too. Thanks in advance! Pic for boring factor lol
Last edited by Boosted04S2K; May 28, 2018 at 02:22 PM.
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Yes I’ve ruled out alternator, I can disconnect battery and car will still run. I just switched the ground to the same grounding spot as the rear Oem grounded wires and car is still acting up. To relocate the battery I removed the engine bay battery ground completely, soldered together the two positive engine bay wires(fuse box, and I forget what the other one comes from) then ran those as one wire to my disconnect switch, then the new positive cable to the other side of disconnect switch and then back to the trunk. Battery is grounded in the trunk. If that helps any.
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I would probably put a short, same size jumper for the ground on the lower side of the bolt to the frame, removing all paint. I'm not sure if the S2000 will run, but most modern cars will still run with the positive side disconnected. The alternator should provide plenty of juice to run the accessories. If yours doesn't, I would look at the alternator output anyway. I was leaning toward the starter getting heat soaked, but since you said the top slugs it, we can rule that out.
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No i meant the same bolt, but underneath the car or on top going to a good clean ground point. If the roll bar had paint and the floor also, the only good contact is the small area of the bolt hole. It will carry voltage, but little amperage. If that doesn’t work, I would put both positive cables on one side of your disconnect and rule it out.
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No i meant the same bolt, but underneath the car or on top going to a good clean ground point. If the roll bar had paint and the floor also, the only good contact is the small area of the bolt hole. It will carry voltage, but little amperage. If that doesn’t work, I would put both positive cables on one side of your disconnect and rule it out.
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So when the car is running the battery is showing 14.3 volts, car off is 12.xx I forget the exact. Car running with headlights, gauges and ac on battery shows 14.3 volts. So with those readings I assume the alternator is good. Car can sit for weeks and fire write up. Something is overheating or drawing power only while driving that once I shut it off it cant produce the voltage needed to start the car. I should add that I'm running aem v2 ems so that needs 12v or it won't start the car. Soooo once warm I'm not getting the 12v needed to start.
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Even though you jumped it at the disconnect on the battery side, you would still be going through it to get to the starter circuit. Did you try it on the buss side of the disconnect? Also, do you have a good ground between the engine and frame still?
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The two positive cables that are in the engine bay I have soldered into one battery terminal, they go to one side of switch and the line from battery goes to other side. Before the disconnect switch I had the wires all hardwired together so it wasn’t going through any disconnect, fuse, breaker, or distribution block and had the same issues.