Hi guys, I have started turning off the ground when I don't use my 348 spider for extended lengh of time. Today I turned the knob back to "on " and nothing. I jumped the car and it started right away only to die at a stop sign down the road. I jumped it again and then it stopped when I came to a stop again. Any ideas on what is going on? The battery reads full as it is only 6 months old. Thanks for any help.
With a digital meter...what is the standing voltage across battery terminals (use the remote boosting points) ? Next, start the car, again check the voltage....what is it?
If the battery is reading good after it stalls it doesn't sound like the alternator but rather a poor ground somewhere in the main system. The alternator is not there to operate the engine but rather charge the battery and if it fully charged it sounds like it is doing its job.
Huh? As I've always understood things, the process is, the battery provides the electrical energy to initially start the car, and then the alternator takes over and runs all of the cars electrical systems, including the engine ignition, and at the same time recharges the battery so it's fully charged ready for the next start, so the alternator is there to run the engine, and to charge the battery.
Yes, but the car will run with a bad/no alternator as long as the battery has enough juice left to run it, so if the battery is reading full it's not a charging system problem.
Start the car and then disconnect the battery and see how far you get. I think we are really saying the same thing because you can't operate the car in a running condition without both working together. The battery is needed for more than starting.
Hi Spiro, For a quick and easy first test if you don't have a multi-meter try one of these. At least you'll know if it's the battery or not. Equus Innova 3721 Battery and Charging System Monitor - Walmart.com
On an old car without the delicate electronics on board you can go pretty far on the alternator alone, however, on a modern car, chances are you're going to do some serious damage to the circuits somewhere. The point I'm making is, the alternator is not there just to charge the battery, (as your post suggested), it provides pretty much all of the electrical supply to the car once the car is running. If that's not the case, how does a car manage to run after a bump start due to a flat battery? From the time the car fires up, you can turn on your lights, heater/aircon, radio, demister etc., etc., immediately. At that time though, the battery will not suddenly and instantly have the power to run everything as it will still be being recharged by the alternator. I stand by My post, once the car has fired up, the alternator is the main source of electrical supply for running the car.
Yep, we are on the same page based on what you just said. You would incur at least a fried alternator trying to run on it alone. I did see this done one time many years ago but that was with a classic car running a generator (simple construction and built like a tank). With the electronics today you would be in trouble trying to do it with just the alternator.
Got this off the internet and maybe it will help clarify the Alternator/Battery discussion. Field current supply is provided from two different sources - from the alternator itself, via the diode trio, and from the battery, via the alternator warning lamp. When you first get in the car and turn the key on, the engine is not running and the alternator is not spinning. At this time, the voltage/current source for the field current is from the battery, through the ignition switch, and through the warning lamp. After the engine is started, and the alternator is up to speed, the output of the diode trio is fed back to the regulator, and serves as a source of current for the field current. At this time, the alternator is self sustaining, and the battery is no longer needed to power the automobiles electrical system WARNING!!! This is theoretical only - in actual practice, the voltage surges resulting from disconnecting the battery can seriously damage the regulator circuitry. All alternator manufacturers strongly advise NOT doing this! This test will not prove the functionality of the alternator anyway, as the engine may still run with a weak alternator output.
Your situation sure sounds like an alternator problem to me. When they die they just croak. Probably the regulator inside. Get a rebuild kit and give the job to an alternator shop. Maybe $200. If the battery is fully charged yet the car starts only to die shortly afterward, then that sounds like grounding to me. After car dies, check battery again. If fully charged, then the issue may be a bad ground, perhaps the alternator grounding strap itself. find it and clean it up. Check for oxidation (white powder). If present replace the grounding wire because that stuff might be throughout the grounding cable.
As long as I drive the car it won't stall. Once I stop it goes dead. I'll keep you posted when we figure it out. Some very good ideas! Thank you!
Battery voltage with the car off should be around 12.6 V if fully charged. When car is running, voltage should pick up to 13.1-14.2 depending on engine rpm/electrical loads. What are your voltages in the above mentioned states? Also, you said it dies when you stop. Do you mean the car will not idle while standing still, or once you turn the key off, the engine will not re-start? Give me a call if you want to go over this. I'm a decent troubleshooter. If I wasn't already over omitted for the next two weekends, I'd tell you to hang right and I'll be down with my tools. If you can hang tight a few weeks, I can come look at it towards the end of the month. Cheers, Mike
There are a couple of things to check. If the battery is in the engine compartment, there is a connector under the air filter assembly that starts to arc and can prevent the engine from starting. If your car has the earlier Delco alternator, Ferrari wired it incorrectly. What can happen is the alternator can fail with no indication on the battery lamp in instrument cluster. Also remember the battery can fail and take a surface charge that a digital volt meter will display 12.6 volts but not start the engine. So there is lots to checking the system out, none of it is rocket surgery and you can take the opportunity to learn more about you car. Try using the search function. FWIW. Jeff Pintler 89 348tb, 86tr, 99 360 3pedal, S-160 Bobcat
Hi Mike, That is correct. When I come to a stop the car just shuts off. Thanks offering but the dealership is coming to pick the car up on Tuedsay.
No battery icon on the dash? Mine flickered a week before the alternator gave up. When it did, my idle got choppy and idled a bit HIGHER. If you rebuild the alternator (easy and cheap), use a DENSO regulator, not the Regitar regulator. (not sure about 348, but this is the case with my 355. My Regitar regulator failed 300 miles after install, possibly due to excessive heat from unshileded Nouvalari headers.... and I had to rebuild the alternator 2x. ) Your problem is possibly there if your alternator failed. If you want, also swap out the rectifier while you are in there, since it is cheap. Call Adam at Nations starter and Alternator. Tell him Brian from Ferrari chat sent you. He was great with customer service, I told him I would send business his way. Hope this helps, IF this is your problem. I had no stalling issues, just wanted to share my alternator experience.
