Ok guys.. I have installed a ton of gauges in my car.. along with a couple different sensor loggers from Innovative. Some of the stuff from Innovative needs a calibration period before the car starts, mainly the MAF sensor, but there is some other things. Right now, I have the power to the gauges coming from the fusebox using an add-a-circuit on one of the spots that has power when the keys turned on. The issue comes in when i turn the key the last click to start the motor, it seems to interupt the power and that recalibrates the sensors while the car is starting, hence getting incorrect values.
Is the power interuption due to the key going into the start position?
If it is, i assume that a push button starter would allieviate this issue by not interupting the power cause the key isnt turned that last click?
I might just be reaching at straws here lol
I have been on the fence about getting the push button starter.. and that would push me over the edge if it solves that problem.

 

I'm not sure whether the car is switching the power from low priority circuits during cranking or not, but it almost doesn't matter. The current surge from the starter motor will pull the voltage down enough to upset most electronic devices anyway so you're not going to avoid it.

 

hey shredder, if your looking for a power
source that is on, in the run & start key
positions, there are a few (according to
the 05/06 wiring guide).

since you have an '07, i won't mention
fuse #'s, because they may not be correct
for your car.

 

I am using one right now.. but it gets interupted when i crank the car

and marcuskeeler, thats a good point.. i have some ideas, but they are all a bit involved and was looking for something simple

 

I wonder, if this is the issue, could it be solved with a capacitor? not a huge 1 farrad one like car stereos use.. but a smaller one?

 

I have the 07 wiring diagram (not handy) [:@]
and there are many key on/start power
take-offs that would solve the problem.
They stay hot during key on AND while
in the starting position. One is your ignition
voltage source.
Asmaller (1/2 farad)cap would work but you would
need to use a diode also to keep the current
from flowing from the cap to the starter during
starting.

 

This sounds like a good plan, and a good time to have a father thats an electronics engineer.. i'll consult him also
I it is the motor cranking thats taking all the juice, there would still be some in the line right? So a multimeter would still read some volts there, and if its the key just turning off, then it would go to 0 right?

 

if you want a push button starter I have one sitting here new in the box, I never got around to the install. pm me if interested

 

The ignition position interrupts power so that the electrical demand needed to run the starter doesn't dip and surge the voltage to sensitive electrical components. That is why all modern cars turn off the radio momentarily as you start the car.

Wire it up through a seperate on/off switched power source, so that you can turn them on or off any time you want, and avoid this problem.

 

of course as you were writting this.. i was clicking the "checkout" button on my order..might not be too late to cancel it.. i'll pm you if its in time.