2002 3.0 X5 engine stops while driving

[workingonit]

Originally Posted by X5chemist

The start up whistle may be the auxiliary engine blower fan. Located on the fender right side. It runs a few seconds at start up to add air into the exhaust. Mine failed a while back. Took three units to keep the service light off. A Hella replacement air pump works great. Two other brands didn't work. If the noise is inside, it's probably the blower motor fan. Mine does it too. Mostly while driving though and not often.



Fuel and bad battery are my primary guesses. Check the battery voltage. If the battery is over three years old, I would definitely keep it on a trickle charger.



Wow, low mileage survivor. Post a small pic or two of it.

I replied to the OP about his problem on another forum earlier, suggesting that his problem might be electrical in nature. And that the whine he heard was possibly the alternator or Secondary Air Pump.

I also said that when my battery went bad (failure to retain above 12 volts for long after charging), I also had the codes he posted. I think that he needs to check alternator output, and localize exactly where the whine originated. I would think that if the fuel pump was whining, he should be able to instantly recognize that it was inside the cabin.



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[80stech]

On this forum he's saying this happened yesterday ??

[workingonit]

see post #1, posted at 1:26am August 10, 2025 https://www.bimmerfest.com/threads/2...1481330/unread

[80stech]

Yeah, I'm not a fan of this confusing stealth cross posting!

[kfm]

Thanks everyone for all the replies. The problem is definitely pointing to fuel pump --

I dug out my old generic scanner and found:

Live: DataStream
Fuel SYS1, OL, not ready CL
Fuel SYS2, OL, not ready CL
Error Codes:
P0171 Pd Generic System too lean (bank 1)
P0174 Pd Generic System too lean (bank 2)
P1083 BMW Fuel control limit mixture too lean (bank1 sensor)
P1084 BMW Fuel control limit mixture too lean (bank2 sensor)

When I turn key to run position, I don't hear any sound coming from under the rear seat, so seems like the pump is not running. The noise I mentioned was coming from under the plastic engine cover - I was able to track this down after realizing had the HVAC fun running, turning that off helped. I guess I will worry that later. May be the fuel system is trying to do something without getting enough pressure from the fuel pump. I watch a bunch of fuel pump replacement videos last night till very late, so task today is open up the access to the fuel pump and see if I get any voltage to it and if it is pumping fuel out.

[kfm]

Originally Posted by EODguy

+1 on the fuel pump

I guess I'll step in as the Foxwell fan
But honestly I recommend you choose the auto option for reading the VIN as sometimes a low battery will let a VIN from another installed car part shine thru and that causes something like a logic loop (guessing the term)

I would also check your battery/alternator voltage, function.

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It did the VIN reading fine. I first did the quick scan option and it scanned a bound of stuff and came back with no error code reported. That was when I went to the specific module scanning mode and got no communication error.

Very disappointed with the Foxwell scanner. Supposed to be a way better scanner compared to the generic ones. But it hasn't given me more info then the generic every time I used both, now it does not even work. I was using it simply based on the believe it is supposed to be better because it costed more, with specific software module for each car make, which of course one has pay for each. The generic scanner works for any car.

One other thing with the Foxwell is that it takes forver to read anything...

[kfm]

Originally Posted by cn90

How much fuel is in the tank?

This could be the infamous O-ring issue that happens when fuel is low (< 1/4)...

What is this O-ring issue? Indeed the fuel was just less than 1/4 tank.

[kfm]

Originally Posted by andrewwynn

That or alternator. When that fails you'll get DSC/transmission errors.

Fuel pumps act intermittent at end of life and last about 5000 hours on average.

Divide your odometer by your average speed to see how close to 5000 hours.

Example my fuel pump failed at about 134,000 and 27 mph average

134000/27=4962.963 lasted exactly the expected amount. Wife's also was within a couple percent of 5000 hours.

With pure gas 4000 hours. E20, 6000 hours. So they have discovered the only good thing about putting an entire year of food for a person into every suv fill up: longer fuel pump life.

I am pretty sure my average speed was more than 27, with only ~70K miles, it would be way less than 5000 hrs. But it is 24 years old.

[80stech]

If you do a search on "E53 jet pump (o-ring)" or something like that. you should get a lot of info on that.

[cn90]

Get a gas can and put in a few more gallons.
If your problem goes away, then it is the infamous O-ring.

I used the modified O-ring bought on eBay yrs ago.
I don't think it is on eBay now