HPFP 30 mile range - damage.

[joeo]

Was going through the owner's manual, and saw this (page 57):
"Refuel as soon as possible once your cruising range falls below 30 miles/50km, otherwise engine functions are not ensured and damage can occur."

I think this is very important! I believe the reason is that the high pressure fuel pump might be damaged if it runs dry (I'm not 100% on this). If the low pressure pump picks up air, the HPFP might run dry for an instant. There is a low pressure sensor to detect this condition to prevent damage to the HPFP.

-Joe
http://www.lovehorsepower.com

[JHZR2]

Lift pumps in regular vehicles are often cooled by fuel flow. There are lots of reports of overheated fuel pumps and burned harnesses from running too low.

I doubt that the HPFP is cooled by return fuel... It is an end-user... maybe so though.

Air is a source for concern, and Id be concerned with picking up particulates from the tank bottom... but the cars are too new to have real issues with that.

[cagekicker]

interesting!

[imported_mega]

this has been an issue on pretty much all in tank fuel pumps for 15-20 years

[joeo]

this has been an issue on pretty much all in tank fuel pumps for 15-20 years

I'm not sure what you mean here?
There has not been high pressure fuel pumps and direct injection on gasoline engines for the last 20 years. Sure, an in tank fuel pump can run dry, and that's fine for a non direct injection engine...it might shudder, or maybe even stall out, but it won't damage the high pressure pump, because there isn't one to damage.

-Joe
http://www.lovehorsepower.com

[jeremyc74]

That same warning is in all BMW manuals, and it has nothing to do with the HPFP.

It's legal speak to remove liability from BMW.

Running the car out of fuel isn't a good idea, but it's very unlikely you're going to do any damage.

[imported_mega]

Originally Posted by joeo

I'm not sure what you mean here?
There has not been high pressure fuel pumps and direct injection on gasoline engines for the last 20 years. Sure, an in tank fuel pump can run dry, and that's fine for a non direct injection engine...it might shudder, or maybe even stall out, but it won't damage the high pressure pump, because there isn't one to damage.

-Joe
http://www.lovehorsepower.com

it's the pump in the fuel tank, it's cooled by fuel, if you go less than 1/4 tank the pump is no longer submerged and it's hard on them

pretty much everything made in the past 20 years has the same issue

[RPM90]

Originally Posted by joeo

I'm not sure what you mean here?
There has not been high pressure fuel pumps and direct injection on gasoline engines for the last 20 years. Sure, an in tank fuel pump can run dry, and that's fine for a non direct injection engine...it might shudder, or maybe even stall out, but it won't damage the high pressure pump, because there isn't one to damage.

-Joe
http://www.lovehorsepower.com

Actually, running out of fuel was a major concern since the advent of fuel injectors. There has been a concern that running injectors dry could damage the seals and impair proper operation.
So, the comment about fueling before a certain point could still be a holdover from way back when.
A direct fuel injector is still a fuel injector whether in the throttle body, port, or in the combustion chamber.

Overall point is, don't run out of gas. However, people have run out of gas and their cars were still fine. But, if there is a "risk", then the manual will try and warn you of if, even if it's not likely to happen. Manufacturers legal departments want to try head off any potential wranglings asap.

[jeremyc74]

Originally Posted by imported_mega

it's the pump in the fuel tank, it's cooled by fuel, if you go less than 1/4 tank the pump is no longer submerged and it's hard on them

pretty much everything made in the past 20 years has the same issue

That's not true and hasn't been for decades. The in-tank pump has a cooling jacket around it that retains fuel even when the tank is low. Vehicle engineers are smart enough to realize people will drive cars around with less than 1/4 tank of fuel, and the perpetuation of this myth on forums like this needs to stop.

Running your car low on fuel WILL NOT damage the fuel pumps. Running it OUT of fuel probably won't either. The real risk is the car running out of fuel on the highway and loosing power steering and brake functions, which causes people to freak out.

[imported_mega]

Originally Posted by jeremyc74

That's not true and hasn't been for decades. The in-tank pump has a cooling jacket around it that retains fuel even when the tank is low. Vehicle engineers are smart enough to realize people will drive cars around with less than 1/4 tank of fuel, and the perpetuation of this myth on forums like this needs to stop.

Running your car low on fuel WILL NOT damage the fuel pumps. Running it OUT of fuel probably won't either. The real risk is the car running out of fuel on the highway and loosing power steering and brake functions, which causes people to freak out.

I'll just disagree with you now, although bmw may have that jacket around the pump

edit, I cant find this fuel jacket around the pump, can you please post more info on where you see this or where you read this? It looks like a normal fuel pump

there's a real reason why all the owners manuals say DON'T DO IT, that is not a myth

[ptack]

Sigh - this has been hashed over again and again. Old school - yeah it may have risked damaging engines to run out of gas way back when. 21st century: this is one of the standard idiot-proofings that reaonably engineered cars come with. How hard do you think it is to program an engine to shutdown automatically when there's not enough fuel?

[imported_mega]

Originally Posted by ptack

Sigh - this has been hashed over again and again. Old school - yeah it may have risked damaging engines to run out of gas way back when. 21st century: this is one of the standard idiot-proofings that reaonably engineering cars come with. How hard do you think it is to program an engine shutdown automatically when there's not enough fuel?

meh those of us that pay attention to the fuel gauge don't have these problems

that said my wife burned up the fuel pump on our f150, running it down to E every tank, it would be nice if the dash lit up and spammed her with warnings when it was down to 1/4 tank, something really annoying like the old shift lights cars used to have, or the seat belt buzzer our f150 has if you are not buckled, that would work too

another car that's really sensitive to low fuel is the current crop of gm ls v8's, it burns up the injectors

[jeremyc74]

Originally Posted by imported_mega

another car that's really sensitive to low fuel is the current crop of gm ls v8's, it burns up the injectors

Bull shit. I've owned 2 of them, and ran every one of them down to the bottom of the tank on just about every one and never had a problem with injectors.

[imported_mega]

Originally Posted by jeremyc74

Bull shit. I've owned 2 of them, and ran every one of them down to the bottom of the tank on just about every one and never had a problem with injectors.

they are well known for that problem

kinda like n54's and fuel pumps, or bmw's and the cooling system's rotting out

just because you did not have that problem on your car, does not mean there is no problem


personally I'm on my original fuel pump, so I guess that means n54's don't have hpfp failures right?

[jeremyc74]

Originally Posted by imported_mega

they are well known for that problem

kinda like n54's and fuel pumps, or bmw's and the cooling system's rotting out

just because you did not have that problem on your car, does not mean there is no problem


personally I'm on my original fuel pump, so I guess that means n54's don't have hpfp failures right?

I was part of several LSx forums for years, and there was never anything tying fuel injector problems to low fuel levels. What happens with things like this is that owners attempt to tie a manufacturing defect to something they've done, just like what's happening to the HPFP. There's nothing an owner can do under normal operation that should cause damage to a part of the car. If running it out of fuel will cause damage, the car should shut down before it gets to that point.

[pit1]

I'm not knowledgeable enough in this area to inject...but

For what it's worth, my ONLY long cranks were on at fuel levels JUST after warning light illumination. Although the final failure occurred around 1/4 tank, cold, level start.

[RPM90]

Originally Posted by jeremyc74

Bull shit. I've owned 2 of them, and ran every one of them down to the bottom of the tank on just about every one and never had a problem with injectors.

I run all my cars from full to empty before I refuel.
The last 2 were 325i and A4 2.0T FSI (HPFP).
Neither had any issues, at least not for the 3 yrs and 32-37k miles I put on them.
I also had a turbo 1990 Laser/Eclipse, I ran that from Full to Empty all the time and no fueling problems for 130,000-something miles.
I even ran out of gas on that car, maybe twice. NO ill affects.

[Spartikus]

I run everything to empty too. I'm always in some sort of rush.

[imported_mega]

Originally Posted by jeremyc74

I was part of several LSx forums for years, and there was never anything tying fuel injector problems to low fuel levels. What happens with things like this is that owners attempt to tie a manufacturing defect to something they've done, just like what's happening to the HPFP. There's nothing an owner can do under normal operation that should cause damage to a part of the car. If running it out of fuel will cause damage, the car should shut down before it gets to that point.

same here, the injectors are a known problem, google it there's lots of posts about it if you dont believe me

Your completely guessing on the HPFP problems too, it could be high ethanol, it could be dirt from the tank because people run too low on gas

it could be a lot of things, that's why some fail and some dont, there's obviously some variables involved, and just because my fuel pump has not failed, and your LS injectors did not fail when you ran out of fuel, does not mean they are all good, obviously there are more variables than your binary view

My e30 radiator never failed, so they are all good right, no e30 cooling problems, same with my e36, never had a problem with it

with your logic every e30 cannot possibly have a cooling problem, BECAUSE MINE DIDN'T SO HAH!


all of you with hpfp problems are faking it mine works fine, so there's no problems, in south park style, there's nothing to see here, move along please





Dont worry folks, ignore your user manuals and run out of fuel, jeremyc says it's ok, it "should shut down" before there's damage

[RPM90]

Originally Posted by imported_mega

Dont worry folks, ignore your user manuals and run out of fuel, jeremyc says it's ok, it "should shut down" before there's damage

Alright man, that's not called for at all.

Look, if you follow the manual no one's saying you're doing the wrong thing.
Some of us simply have more experience and knowledge with things automotive that we're not as worried as others are.

The owners manual is an excellent resource, however, there are many many things in there written to appease the lawyers. Hell, just look at all the freak'n warning comments, statements, and logo's all over the manual and the car. Is it really necessary to tell me that "objects may be closer than they appear"? Unfortunately, it IS for some people.

YES, if you are running low on fuel, and you don't refuel soon, guess what?
YES, you WILL experience running problems, cause you will soon run OUT OF GAS.

[imported_mega]

Originally Posted by RPM90

Alright man, that's not called for at all.

Look, if you follow the manual no one's saying you're doing the wrong thing.
Some of us simply have more experience and knowledge with things automotive that we're not as worried as others are.

The owners manual is an excellent resource, however, there are many many things in there written to appease the lawyers. Hell, just look at all the freak'n warning comments, statements, and logo's all over the manual and the car. Is it really necessary to tell me that "objects may be closer than they appear"? Unfortunately, it IS for some people.

YES, if you are running low on fuel, and you don't refuel soon, guess what?
YES, you WILL experience running problems, cause you will soon run OUT OF GAS.

what was uncalled for was jermey making snide comments on another thread, simply because he does not agree with me

if we had a vote, I would vote follow the owners manual guidance on this issue, if you all think it's ok to run that low, or out of fuel, good for you, I sure don't agree with you

Most people here were not born yesterday, and realize that not every car will have a hpfp fail, or a fuel pump burn up due to an empty tank, but that does not mean that it wont happen to somebody else "just because mine did not do it"


I'm just going to unsubscribe from this thread as I"m sure there will be more smart comments, and anyone reading will no doubt be able to understand my opinion on the matter

[jeremyc74]

Originally Posted by imported_mega

same here, the injectors are a known problem, google it there's lots of posts about it if you dont believe me

Then link to it. Why should I search for something YOU claim exisits. If it's so rampant it shouldn't be a problem to find some solid proof. I owned a '98 Trans Am I put 130k miles on, and a '06 GTO I put 70k, and was a member of several forums the entire time. There is NO PROOF AT ALL that inject


[

Originally Posted by imported_mega

all of you with hpfp problems are faking it mine works fine, so there's no problems, in south park style, there's nothing to see here, move along please





Dont worry folks, ignore your user manuals and run out of fuel, jeremyc says it's ok, it "should shut down" before there's damage

Stop acting like a drama queen. I never said the HPFP problems were fake, and you know it. I said that the warning in the owners manual has NOTHING TO DO WITH THE HPFP. If that was the reason for it, why the hell would BMW put it in the 128i manual?


You're constanly putting out bad information on this board, and I'm tired of seeing hearing your BS.