Tufhchc

My 2000 Nissan maxima has brand new mass air flow sensor my fuel pressure regulator is good no raw fuel coming out and I have a good battery (tested ) and alternator is new and so is battery
But my car shuts down sometimes and I can't even start it again becuse there is no power whatsoever ever

2damax

Shuts down meaning it dies while driving? Where did you get new alternator and MAF? If the car dies and won't start again how do you eventually restart it? Are there any symptoms right beforr the car shuts down?

Max_Gator

Yeah, you need more details.

However, this seems very similar to a problem I had. Alternator died and took battery with it. I replaced both.

Drove for a couple of days and the car would shut off. But it would start up again strangely enough.

Turned out the alt was no good.

It could also be that your battery cables are loose. They lose contact while driving then when you try to restart they work. I've had this problem too.

Tufhchc

When I had a engine check light on I had the code po171 come up with also relates to po174 but I already went down the check list for most of the stuff I only think it could be like 2 or 3 things but I got the alternator from Orielys and
It hada to be jumped to restart it but if some times when it dies and I don't restart it right a way it starts but as soon as it dies the air bag light comes on in the upper dash and nothing works

2damax

I would bench test the alternator.

Tufhchc

Some places say with the po171 code it has a lean or rich fuel in bank one or bank 2 saying the cars exhaust is getting too much oxygen and I believe that part but the mass air flow is brand new and I have another one sitting here but I was temped to say to check my fuel pressure or my fuel pump or my injectors becuse it's not an air issue it's a fuel issue causing it to shut down ?

2damax

The amount of fuel can be related to the amount of air the car reads. Where did you get MAF from?

Edit: also how many miles are on your car.

Max_Gator

This. I'm betting alternator is bad. Happens.

Op ... Did they test it before you purchased.

After my issue, I had discount auto test the alternators they wanted to sell me. 2 of 3 were bad.

Your car is restarting after sitting because it gives battery time to recharge itself somewhat.

Also, we would all appreciate some punctuation.

Tufhchc

I just started the car and took the positive off..butt I had everything off in the car and the alternator DIdnt shut off.
My maxima has 161000 on it, full synthetic,cold air intake,performance exhaust brandnew mass air flow from a shop they put it in

2damax

Fnd out if the shop use OEM MAF. Doesnt matter if it relates to this issue or not. Has to be OEM.

I don't really understand this test you did by taking the positive off. It doesn't test the alternator under load or over the course of a drive or anything.

Did you bring the car to a shop with this issue and they did all this work and still no fix? If yes then just bring it back. If no and you did the work...bench test the alternator...or at least read the volts at the battery.

Tufhchc

So it couldn't be anything wht the font o2 sensor ? Or the injectors ?
I have an oem sensor at home I'm going to put it in and see if that one fixes the problem.i called the shop they said after market..

2damax

Aftermarket MAF sensor are known to fail om this car. From your description o2 sensor and injector seem unlikely.

Tufhchc

Checked ground wire from battery to engine it is right also but if it's not an o2 sensor. And not the injectors then why is it, when it shuts down it gives me the oil and battery light and service engine soon light ? That's where I get confused MAF is replaced

2damax

Dude everything you have said points to alternator. We have told you to bench test it. Do it. And then replace the alternator with one that passes the bench test.

Tufhchc

It ended up being a short
So like my car is dieing and then doesn't have any juice