DelSolMarine

I am trying to trouble shoot my voltage problems with my fully built turbo del sol.... At idle the car will die if I turn the headlights on (hids w/ ballasts) and when the spal fan (w/ relay) turns on.... I am running a walbro fuel pump and bosch inline fuel pump (w/ relay) as well... With the bosch fuel pump unplugged the car idles at 14.0 volts, and when i hook the pump up it drops to around 13.8, then when the fan or headlights are turned on it goes to 13.5 and slowly lowers... and when all 3 are on the car starts and dies after about 3 seconds...

I have gotten ride of the yellow top battery which was 450cca and replaced with a marine deep cycle 600cca battery which i relocated to the trunk due to the catch can kit.... there is a 2 guage wire ran up to the front of the car.... i replaced the alternator with a known good one and no change... the battery in the trunk is grounded in the trunk (2 guage) and i ran another ground to the front of the engine bay (4 guage) and still no difference... i added another 4 guage ground to the valve cover and that didnt help either.... i have contemplated a high amp alternator but i dont see any other guys with built turbo cars doing that so... i dont know...

MadVTI

My mates teg on hondata s300 does this. tried earths, feeds, ecu's and alsorts and gave up in end. had to map with a load on it. i.e lights and he drives with them on all time. goes rich when no load on it. may be an eld fault but couldnt sort.

ashb82

adjust injector battery offset

th3pwn3r

I suggest checking your ground wires again and you could also run some 0 gauge wiring for good measure.

1SlowSi

The 2 gauge is fine since the stock is smaller than that. I would double check your grounds throughout the car and make sure they are secure and not corroded. I would try to use a stronger alternator as well that puts out more amps. My OEM one was a tad on the weak side. My lights would dim and seem to run a bit on the dim side. When i stepped on the gas the lights on the cluster would brighten up so beautifully haha.

th3pwn3r

But the stock wiring wasn't meant to run all the way to the back of the car hence the 2 gauge wiring. The shorter the run the smaller gauge wire you can get away with. I'd bet it's a ground issue though.

RedneckRicer

what crank pulley are you running? some crank pullies underdrive the alternator

jDMJeRk

I agree with the 0 gauge.. I know 2 gauge is big, but obviously its not big enough.

Make sure your running the same size wire to the alternator too... I ran 4 gauge and that wasn't enough to keep my battery charged either.

How and where are you reading this voltage?

DelSolMarine

The 2 gauge wire is suppose to be plenty big... i am not running any sort of amplifier or anything like that its just an upgraded fan, hids, and and fuel pump...

I do not know what injector battery offset is however i am going to look into that...

i have a gsr block with an ls crank in it but i am not sure what crank pulley is on the block... i do not quite see how that would effect anything unless i had one of those stupid under drive pulleys which i do not...

i am reading the voltage at the under hood fuse box...

i am running a 2guage ground at the battery to the shock tower bolt in the trunk and i also tried a 4 gauge wire from the battery all the way to the transmission (by distributor) with no improvement...

i just dont see how the wiring can be the problem at this point... i am going to research the injector battery offset thing considering i do have the ID1000s so maybe there could be some issues with those

th3pwn3r

I should have been a bit more specific. I should have said to upgrade the "Big 3" to 0 gauge wiring.

DelSolMarine

so i switched from my race gas map to my pump gas map and now its at 14.4 volts with everything running... maybe it was the injector battery offset thing that was different

DelSolMarine

yea just kidding... its better than the race gas map for sure but its still doing it at random.. sometimes it will be around 14.4 then all the sudden its at 13.1 or 13.2 really weird

ashb82

what tuning software you got. also you got a wideband

DelSolMarine

I am using Neptune RTP. Yes I am using an AEM Wideband but i need to replace the sensor.

ashb82

my car was doing the same thing i disabled eld and then adjusted the battery offset. What was happening to my car would lean out and shut off as the voltage dropped.

I COPIED THIS FROM XENOCRON

Good to have a volt meter on the battery at all times during this test.

Start the car, bring to full warm and get the car to idle steady. May help to open the idle screw some to bring the revs at idle up over 1000, or maybe unhook a vacuum line to do so...

Get your AFRs perfect to what you like, get them steady. Make note of the voltage.

Next, hook up good battery charger set to START with the car running. Also helps to have a REALLY good alternator. Battery Voltage should be higher at this point, once you take the charger off, battery volts will drop some, see how AFRs changes and adjust offset until they dont.

Next, unhook the alternator, watch battery volts drop some. Make note of AFRs change and voltage. Adjust offset...

Turn on accessories, A/C, Headlights, High Beams, Fog lights, hard wire fan to be ON, always...upon each individual one, battery voltage will likely drop some more...although, this might not be a great method because I assume ELD does SOMETHING here...who knows.

You can just let the car continue to idle with the alternator unhooked, watch the battery voltage drop off until the car wont idle anymore...adjust offset as battery voltage drops.

My guess is that once you do this on a set of injectors, it will be relatively the same if you have to tune another car later...

Maybe it would be good if we all did this test the same and posted our resulting offset numbers. Then someone could code them into a Plugin which a user could select a set of injectors in that plugin (kinda like AEM does)