Battery Voltage at WOT
 

What is battery voltage supposed to be at WOT?

Rev normal it is about 14V

Driving WOT it drops to 12.5-12.6
Is this normal?

Re: Battery Voltage at WOT
 

voltage should remain the same throughout by design of an alternator. big fat injectors hogging all the voltage? lol.

whats the car? setup? ------ed wiring?

Re: Battery Voltage at WOT
 

Car is 99Si
Stock wiring and b16a motor

alternator was rebuilt after i put new battery.

Reving the motor, and idle, it is 14V

Only on load it drops down. WOT 12.6
wtf is up

Re: Battery Voltage at WOT
 

load by electrical or load by drivetrain/car in gear?

Re: Battery Voltage at WOT
 

Load with car in gear
I am using Ectune.
Eld is disabled.

im stumped!

Re: Battery Voltage at WOT
 

The ELD will output .1 - 4.8 volts to the ECU. This reference voltage is what tells the ECU to increase or decrease the field strength in the alternator, which in turn bumps up the output of the alternator.

Re: Battery Voltage at WOT
 

it is disabled stock
should i re enable?
Do you think this is the cause?

If not, what the hell do i check

Oh when i crank over, volts recorded by ecune was 7V
thats low right

but its a brand new battery
and rebuilt alt

Re: Battery Voltage at WOT
 

rebuilt alternator rebuilt by mexicans in a sweatbench shop, could be part of the reason. the other is, if honda equipped the car with ELD why would they disable it :1

you're essentially running a 1-wire altenator in a FI car. enable that ---- youre going to ---- your tuning up with changing voltages (someone correct me on the honda logic if i'm wrong)

Re: Battery Voltage at WOT
 

Car isnt FI.................... AS YET!

Cool i will re enable it tomorrow

do you think thats causing this mess?

Re: Battery Voltage at WOT
 

question IS

why will it do it when in gear

should it not happen when i rev in Neutral ?

Re: Battery Voltage at WOT
 

Way to copy and paste

Re: Battery Voltage at WOT
 

fi = fuel injected

forced induction is a supercharger, turbos are welcomed induction :)

Re: Battery Voltage at WOT
 

Uh, no it doesn't. It detects high loads at idle and the ECU raises IACV duty to compensate for drag. It's a good idea, but doesn't really do much and that's why Honda disabled it on half of the cars they made. The ECU directly monitors system voltage and can tell what to do with the alternator if it's internal regulation circuitry isn't doing the job. Which is another ineffectual design seeing as how you can disable alternator control and it doesn't change voltage.

Jon, stop handing out Honda ECU advice when you have zero experience with it. This dude has a problem with his alternator or grounds.

Re: Battery Voltage at WOT
 

thanks for the advise everyone
i re enabled eld just to check.
it is the same problem

Re: Battery Voltage at WOT
 

:1 i didn't hand out anything that wasn't already in the internet

Re: Battery Voltage at WOT
 

altenator was rebuilt
i checked grounds
everything seems secure

hellpp

Re: Battery Voltage at WOT
 

take your grounds off, clean the contact point and your terminal end.

tightening does not make your ground magically work

Re: Battery Voltage at WOT
 

With ELD enabled it causes more problems
volts drop to mid 12,s even crusing.

I Left it disabled. much better

Re: Battery Voltage at WOT
 

Complex, you need to stop talking about ---- you know nothing about. Your "advice" is detrimental.

Re: Battery Voltage at WOT
 

as least he IS HELPING :y

Re: Battery Voltage at WOT
 

prove to me that cleaning your ground surfaces is not the way to make contact, and that tightening them tighter is the ONLY way to make contact.http://forums.moproblems.com/images/smilies/yoyo2.gif

Re: Battery Voltage at WOT
 

who is that hot chick in your avatarr

Re: Battery Voltage at WOT
 

On my car it fluctuates a bit, but my cars ------- like 25 years old. Get it fixed tho, cause I know when my car would drop under 12v the ecu would do really wonky things like reset.

Re: Battery Voltage at WOT
 

i wanna fix it]but dont know what it is

Re: Battery Voltage at WOT
 

and to quote you JD, you did not answer me when i asked you about this thread last night. ------- :7

Re: Battery Voltage at WOT
 

i read a recent topic on pgmfi saying that the alternator output is decreased/cutoff at WOT to maximize engine power to the wheels. The reduced voltage may be perfectly normal.

Re: Battery Voltage at WOT
 

You ruined the crediblity of that post with the word recent.

OP your making this harder then it is. a mountain out of a mole hill.

Yoseph has said and I'm sure Chuck would agree clean up your grounds and replace the alternator ,or as the mexicans at the Upull yard call it an Altornado with a know good one and rock that ----.

Re: Battery Voltage at WOT
 

lol yea i know right? There's still like 2 or 3 knowledgeable people over there though, relic1 seems to know his ----.
http://forum.pgmfi.org/viewtopic.php?f=40&t=17638

Re: Battery Voltage at WOT
 

thats me :)

Re: Battery Voltage at WOT
 

i've been wondering this as well lol.

OP:
what input are you using for AFR datalogging?

Re: Battery Voltage at WOT
 

Innovate LC1 - Serial Input with Ectune.

I wired the Blue And White Together, and ran them to the thermostat Housing Ground.
Power, wrapped wire arround a fuse leg, 10am, and plugged it in.

IS that okay

Re: Battery Voltage at WOT
 

twas a grounding problem

Re: Battery Voltage at WOT
 

wow, i guess we missed that one

Re: Battery Voltage at WOT
 

so who is the chick in your avatar?

Re: Battery Voltage at WOT
 

i made a thread on it. you aren't allowed to view it.

search for the answer :l

Re: Battery Voltage at WOT
 

I don’t know it this helps but I did find a lot of eld info in the books. I have not had time to play with my transistor thing yet. https://www.homemadeturbo.com/forum/...topic=100718.0
I have no clue if the alt disables at wot? Sounds logical but I have not played around yet. Said under 3500 so maybe not.

Re: Battery Voltage at WOT
 

Wot is when you really don't want a sudden voltage drop messing with sensors readings. If I were designing my own ecu to run an engine I wouldn't want the car running off the battery at wide open throttle.

Re: Battery Voltage at WOT
 

No offense, but if you were designing an ECU you would use voltage regulators to provide a steady 5V input to your sensors regardless of Battery Voltage. It would be a non issue.

Re: Battery Voltage at WOT
 

Have you ever tried to tune a car with a dying alternator. it's no fun. especially when trying get injector battery offsets to play nice.
I'm not an all knowing guy or anything but Ive fooled around with a lot of cars and I know that when an alternator isn't charging it has an imidiate affect on the car. voltage dips at wot can even mess with wideband readings.

Re: Battery Voltage at WOT
 

True, and that's why the inj battery offsets are important. Injectors aren't under 5V regulators. they get as much voltage as possible to maximize effeciency.