No man, alternators never just shut off.

 

I didn't think so. Just to give you a little background, I'm not ASC certified but I am mechanically inclined. I worked at a dealership for a few years as a mechanic and done a lot of side jobs through the years but there's still a lot I don't know. I was pretty sure that the alternator doesn't shut off at any time that the motor is running but that's what the one in my Rover is doing intermittently. It will shut down so the motor is running straight off the battery and it's let the battery get down to 11.5v before it kicked in and brought it up to 13.1v or so but it only stayed on for a little bit then stopped charging again. I think the battery is a little weak because the previous owner let it die a couple times but it still seems to hold a charge pretty good.

 

Take the battery to an auto parts shop that has an advanced tester. No need to guess.

Think of the generator as a hose, the battery as a bucket that you don't want to overflow and the car as another bucket with a spigot where the water must come out at a constant pressure as much as possible to keep things going.

The regulator will fill the battery bucket to the rim and them stop dumping water into it, occasionally topping it up as needed. That water will be used to turn the starter and get the car started, and it needs to be recharged once the car is running.

The regulator will also, at the same time, try to make sure the other bucket has enough water so the spigot will not lose pressure. Any excess water is dumped overboard (that's the regulator dumping the excess power as heat). The generator cannot stop generating. It is mechanical and as long as it turns it generates electricity.

 

The alternator is presumably not excited during engine start (that would be a big and unnecessary load on the alternator with the starter engaged).

On modern cars the alternator will likely be managed by the ECU to not charge the battery if it doesn't need it, ie just maintain 12.X system volts instead of 13-14V. A bad battery, or bad connections or grounds, might confuse that logic.

 

LR doesn't say the LR2 has an alternator, it says in the service manual that it has a generator. But then later on it says it includes an inverter to convert the alternator output to DC current. Call the shrink. The voltage control is done by the ECM (Engine Control Module). There's quite a bit of text explaining how it works. I just wanted to simplify it.

 

You did good. I understood how you were explaining it. I've traced, disconnected and cleaned all ground wires that I could find, had battery tested- good, but I still might change it because my friend let it die on her a couple times then it sat for a long period before I even started messing with it. Plus it's only just over 600CCA and I believe the LR2 requires more. Please correct me if I'm wrong. I started to run some more tests on the alternator but for the most part it stopped putting out any voltage at all to the battery. I do believe it gave up and doesn't need any more tests. Can you suggest a good place to get a replacement? Also, I'm still getting P0087- low pressure at the fuel rail. It's hard to start unless you pump the accelerator but once it starts it run like a champ. With that scenario which would be best a new fuel rail pressure sending unit, fuel pressure sensor or EVAP purge valve? And what type of fuel additive/injector cleaner would you recommend? I want y'all to know that I appreciate all the info I've been getting from y'all. I've learned a lot in the past weeks. Thanks. Please let me know your recommendations or what other info you might need

 

I got mine at Autozone. Replacing it is quite a bit of work, get ready for that. You have to remove the intake manifold and other things to get to it. Stupid Volvo design.

I would also suggest you fix one thing at a time. It may be that the P0087 is related to the power issue and may resolved itself once you get the electrical working again.

 

Ok, awesome. Do you know anything a type of fuel additive I think specifically for Rovers? I remember reading about it in one of the forums (or sub forum) they said it improves quite a few things but I haven't been able to find it again. It doesn't have a regular name but something like a bunch of letters and/or numbers? And here's a bummer, my girl had originally bought the Rover for her eldest granddaughter but she started having electrical problems with it so she parked it until she figured who she wanted to work on it. That's about when I made an entrance to where I'm at now and told her I'd work on it and save her from spending a small fortune at the dealer or a shop that might not be into Rovers like we are. But in the meantime the granddaughter got a car. And now my girl doesn't want to keep the Rover. So as soon as I get this little bit of electrical right and do a little bit of cosmetics, not much, she's going to sell it. Everything goes right, which I really don't see any problems, she's going to be asking $6500. So maybe something keep in mind or pass along. Thank you for your input and your opinion
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Don't use fuel additives. Just premium gas, minimum 91 octane. Most of the crap out there is snake oil.

$6,500 for a 2009 may be a little wishful thinking unless it has very low mileage and a totally clean Carfax.

 

I have determined that the alternator is bad and am getting a new one. Where do you recommend getting a replacement without costing an arm and a leg and a few fingers?