Tompuma28

2011 g37 XS

I went to start my car yesterday after it being completely fine and the dash board blinked a bunch of times before starting and it struggled to start, once started I tried backing up and it was fine except the gas pedal would not work, same thing in drive! It would only move under the idle power. I let it sit and today it starts and drives fine with the gas pedal working, except when starting the dash board still blinks and struggles to start. Any ideas? Anything is greatly appreciated.

ChefMatt

A starting point would be to check your connections to the battery, check charging voltage when running.

PhatherPhish

As matt suggested check the battery connections and charging voltage. Make sure they're tightened and clean off any corrosion with vinegar (if you do this, disconnect it and be careful not to short the battery).
If the battery checks out fine, the alternator would be the next place to look. Same steps as the battery. Make sure they're tight and free of corrosion. If you are able to start the car check to see if the battery light blinks on the dash while giving the engine a few revs and while at idle.
If it does that would mean your alternator is probably going bad.

McBoing

Sounds like an alternator issue. A friend of mine had a Jeep that spazzed out on him while driving, I’m not entirely sure the details as I wasn’t there, but I know his entire cluster illuminated and glitched out. Electronics don’t like too little or too much voltage. Get yourself a multimeter or use one that you have, and test the cables with the car running for voltage. Nominal should be around 14v DC. Your battery is 12v but likely reads higher due to its charge and depending on its age. As the battery drains, voltage will decrease. As the battery charges, it increases up to a maximum capacity. To do so requires higher voltage than nominal for the battery, aka charging circuit. Most times when the alternator dies, it produces weaker current, such as 12v or even 11v, which means your battery will never be able to pass that voltage leaving it less than fully charged until it is unable to start.

You have resistors, diodes, bridge rectifiers and coil windings inside of the alternator, changing your rotating belt motion into the appropriate current. One thing that could be happening is it that it is unable to produce the amps to drive the vehicle in every foreseeable way, yet enough time running will still sufficiently charge vehicle. So when an electrical device tries to pull x amount of amps from the circuit, it incurs voltage drop and your ecu and other sensitive equipment really does not like that. You could test this by turning off all lights, radio, ac, and anything that consumes electricity and seeing if that helps your issue. There is no real way of testing amp draw without specialized equipment that can handle the massive amount of amperage from that alt, so for your own sanity, don’t test the amperage or you will be looking for new fuses at your local auto parts store.