PDA

View Full Version : Voltage drain causes rich condition!?


NemeGuero
08-02-2006, 02:49 AM
So.. at idle with my headlights on... my AFRs read from 10ish to "rich".. after I turn the headlights off.. they climb back to 12.9 and 13s.. (I have a rich tune)..

Headlights on... 10s to "rich"

Headlights off... (high 12's to 13s) <---Normal

Question: Is the drain from low voltage to my walboro? Bad alternator? Low voltage to injectors?

How do I go about diagnosing?

I'm gonna try the fuel pump hard wiring kit...
Any other insight, suggestions?

Thanks Zilvia.

spdfreek0o
08-02-2006, 07:09 AM
do you get a stumble, kinda like a miss but not?

mobilesuit818
08-02-2006, 10:14 AM
If you do not have the voltage needed, hence, a bad alternator, the computer wont have the reference voltage needed to give to the inputs, and outputs, so, yes that does explain why your car is running rich. or missing.

Tung

slider2828
08-02-2006, 10:43 AM
Yes it will.... I have measuring equipment in my car for tuning and it is very voltage sensitive. Before I made a grounding kit for my car, I would notice that by stepping on the brakes, it would fluctuate my AF by .5 hence 14 instead of 14.5. It would fluctuate 1 AF level if I had my lights on and stepping on the brakes hence 14-13. This is of course at idle, I believe that under driving conditions, I don't think it fluctuates very much but during idle or stop light stand still it does..

I dunno most boost controllers have a voltage checker built in, you can use that to check it. Also you can put a voltage meter on your battery and test the voltage in your battery while at idle with the headlights on and off.

Secondly, what i think helped me a lot was grounding the ignitor ground to the a good chassis ground instead of harness ground. Harness grounds are usually really crappy and I have a burnt ignitor to prove it. I don't think you need to pull stuff out yet... Do a couple of things first and then possibly make your own grounding kit which is discussed here in the forum or you can just ask me. Do you have a light weight pulley system with some audio equipment, see if turning off the audio equipment helps as well.

Fluctuating voltage sucks ass and in a 240 it always happens cause nissans just suck in that way.... but not as bad as Toyota Supras.....

NemeGuero
08-02-2006, 11:58 AM
spdfreek: No, no stumbles.. unless I'm on a quick Decell but that's MAF related I believe.

mobilesuit818: I've also got a trunk mounted battery.. Maybe I have too much resistance through the wire.

slider2828: Where did you run the wire for your "grounding kit?"
I'm KA, but I'm sure I can ground something on my dizzy better.

mobilesuit818
08-02-2006, 02:09 PM
Trunk batteries are good, only if you have a thick ground wire such as a 4 guage, and make sure that the contact point of the body is paint, and rust free.

Normal voltage with engine running should be around 14 volts.
If you have 13 volts, it probably means your alternator is not charging. I would change that, or at least do a voltage drop test.

A ghetto way of testing to see if you have a short is to turn off all your accessories, alarm, radio, closed the door, basically turn off everything that you can, and turn the car completely off with the key out, and take your positive terminal out and slightly touch the terminal to the battery, if it sparks a little, that means you might have a short, which could be one of your problems.

Tung

slider2828
08-02-2006, 02:31 PM
Well if he did have a short, I think he would have much more problems than that. Mine only usually runs around 13.4 volts stable when it is running as my blitz fatt dc timer says and I believe it to be pretty accurate. Yes if you have a trunk mounted battery, please at least have a 4 guage if not a 2 guage.

Basically I took a jumper cable from sears about 30 bux. Make sure it is 4 guage wire then get a big cutter and cut the ends. Go to home depot or pepp boys and get gold wire terminals. Go to kragen and get some battery terminators, basically a fly nut that goes to the negative of the battery. Ground all the following points directly to the battery negative terminal. Head, intake manifold, chassis, and block. Then if you got a little more money, see if you can get a 4 guage distribution block from radio shack. The 4 guage can split into (4) 8 gauge connections. Then you ground the remaining 8 guage wires from the back of the head to distribution block, ignitor to the distribution block, and valve cover to the distribution block and if you want some real fun, add an additional ground to the alternator to the distribution block. If you have any questions lemme know. Remember the distribution block goes directly to the negative terminal of the battery. Hence now you have a Circle Earth system that beats anything out there....

Before I get flammed, the jumper cables from sears decco are very high quality. 99% copper, up to 400 degree's heat resistance and is a 4 guage wire with amperage up to 500A....

Oops one more thing, don't forget to electrical tape all connections... Good Luck

-Ken

NemeGuero
08-02-2006, 02:43 PM
That's a SHIT load of grounds.. hahah

kernel
08-08-2006, 08:28 AM
I do have the same issue, does making more grounds will really fix the problems?

slider2828
08-08-2006, 11:22 AM
Its not making more grounds bro... all the grounding points are already there, but ground to the harness and weak grounds. Secondly if you read correctly the grounds are DIRECTLY tied back to your battery terminal. Voltage is stage and only good because of grounds... Its a system.... A better ground = stronger voltage....