Oscilating battery voltage

Itsuki · Post by **Itsuki** » Mon Nov 08, 2010 3:45 am

Hi,

My battery voltage is always going from 13.7v to 14.5v.

Recently, the battery went down and I had to charge it, plugged with another car. I don´t know the oscilation it´s because the battery it´s low or it´s because there a bad ground conection in the car.

Another issue I have, with a MAP calibration, the car when enters in open loop, goes suddenly lean. But if you see the time of the injectors it´s bigger than when goes in closed loop. And the AFR in closed it´s fine.

See the datalog in 4:33 and after.

The car has the rev limit to 3000rpms because I left it in the workshop to repair some scratches.

Thanks.

Post by **Hondata** » Mon Nov 08, 2010 9:01 am

I would not drive the vehicle with its current calibration.

There's multiple problems (battery voltage, air fuel, engine overheating, IAT high) so you should go back to a known good position and then find out what might be wrong. Update the return to stock calibration for the FN2. Then start looking for the cause of the problems which you're seeing. If the battery voltage is still going from 9 to 15V, then look for the cause of that first. Check all fuses, inside and out, as well.

Itsuki · Post by **Itsuki** » Mon Nov 08, 2010 1:17 pm

Ok. The problem it´s that I have 750cc injectors. Could I take the stock calibration with MAP and multiply the fuel by the relation of stock injectors and the 750cc ones?

310/750 = 0,413

Post by **Spunkster** » Mon Nov 08, 2010 1:51 pm

I would suggest putting the stock injectors back in so you have one less thing to worry about and focus on resolving the other issues first.

civicRSA · Post by **civicRSA** » Wed Nov 10, 2010 12:26 pm

Is there any extra electrical load when the battery voltage dips. Switching on stereo, Aircon coming on, lights ect? If the battery dips with extra load then it could be a faulty battery. Have it load tested.

Are your cooling fans switching on?

You could also have a faulty O2 sensor here.

Itsuki · Post by **Itsuki** » Wed Nov 10, 2010 2:02 pm

I think the problem could be the bad wiring of two gauges that I have.

I hope to get the car the next week and solve the problem.

Thanks for the responses.

I´ll post any news.

Itsuki · Post by **Itsuki** » Sun Nov 21, 2010 1:50 pm

I solved the problem with the voltage. A bad wiring with a new gauge and the conexion with the lighter

Now, I think I have a leak in the intake manifold :oops: