The NEW Fuel Filter Writeup Thread
07-05-2005, 02:31 PM
#82
Originally Posted by Ammi
I took my pump unit out again and noticed the o-ring was in the gas tank! I took it out and I tried to properly place it but for some reason, it was way stretched out. It was a lot bigger than what it used to be. I had to cut a section off to make it fit. I placed everything back carefully and now my gas gauge seems to be working but I'm not 100% sure. I'm going to fill up again tomorrow and see if gas needle rises or not.
07-06-2005, 05:10 AM
#84
I have observed 5-10% improvement on gas milage and a better response in high RPM range (it used to feel like it is choking when accelerating in 5K range). I drove about 3K miles since I changed the filter and the improvement has been consistent. Note that I have not changed my driving habits nor driving route to work (I drive about 80 miles daily to work and back).
08-10-2005, 03:29 PM
#87
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Originally Posted by kcowden
Nice write up!! Same question here.... at what mileage should you consider the change?
i wouldnt, the fuel filter is a lifetime filter, it doesnt need to be changed... seriously.
Originally Posted by steven88
don't listen to the dealers...they don't know **** anyways...
what about the engineers... do they not know **** either... because theyre the ones who designed the filter NOT to be changed, except when replacing the fuel pump.
...enjoy
08-10-2005, 04:26 PM
#89
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lol... i make a living off of changing dirty fuel filters, and the like.
ill say it again...
THE ENGINEERS DESIGNED THE FUEL SYSTEM SO THE FILTER WOULDNT HAVE TO BE REPLACED
its simple really. traditional return efi systems just run the pump at full volume for its operating pressure, which can be around 10 times or more the fuel that the engine needs at certain times. most fuel gets recirculated through the filter several times it goes up through the filter, into the rail, through the pressure regulator, and back to the tank, minus what small amount gets used by the engine in the 5 to 10 seconds a modern fuel pump could fill a fuel system.
in returnless systems, only the fuel that gets to the engine goes through the filter, which makes the filter life usually longer than the pump itself.
if you douchebags wanna tell me i dont know what im talking about, then feel free to replace you fuel filters, spend the extra money, waste your time. its a rare occasion that a filter in a returnless system causes a problem.
in short, dont replace the fuel filter unless you have a documented fuel pressure drop under heavy load. and even then, you might as well get yourself a new pump while youre in there.
ill say it again...
THE ENGINEERS DESIGNED THE FUEL SYSTEM SO THE FILTER WOULDNT HAVE TO BE REPLACED
its simple really. traditional return efi systems just run the pump at full volume for its operating pressure, which can be around 10 times or more the fuel that the engine needs at certain times. most fuel gets recirculated through the filter several times it goes up through the filter, into the rail, through the pressure regulator, and back to the tank, minus what small amount gets used by the engine in the 5 to 10 seconds a modern fuel pump could fill a fuel system.
in returnless systems, only the fuel that gets to the engine goes through the filter, which makes the filter life usually longer than the pump itself.
if you douchebags wanna tell me i dont know what im talking about, then feel free to replace you fuel filters, spend the extra money, waste your time. its a rare occasion that a filter in a returnless system causes a problem.
in short, dont replace the fuel filter unless you have a documented fuel pressure drop under heavy load. and even then, you might as well get yourself a new pump while youre in there.
08-11-2005, 05:40 AM
#91
THE ENGINEERS DESIGNED THE FUEL SYSTEM SO THE FILTER WOULDNT HAVE TO BE REPLACED
Riiiiight... The filters are engineered to last forever just like the plugs are good for 100K and Tranny oil and filter for 60K...
Dude, filter is a filter. The purpose of it is to take crap out of the fuel and in a perfect world fuel would be clean and we wouldn’t need filter at all, but reality is that fuel has crap in it and it gets collected in the filter. See the photos above I took of the filter that had 70K on it. I will attest that I got a better throttle response and better gas mileage after I replaced it. I will say that the filters in our maxes are larger than conventional fuel filters and as such will be capable of retaining more crap than others and will likely last longer than standard fuel filters…
We all have our prerogative, it is up to you if you want to change it or not… I chose to change mine and do not regret it…
08-11-2005, 07:43 AM
#93
Sorry but I threw out the old o-ring and do not have a pic of it. I got mine from Dave too and he sent me a correct one (it is about 4-5" in diameter). That is all you need in regards to parts...
08-11-2005, 12:41 PM
#94
Originally Posted by ZIPPIN
can you please post a pic of the O-RING?
I got the ring and the filter from dave. That is all i need right?
I got the ring and the filter from dave. That is all i need right?
08-11-2005, 02:21 PM
#96
Originally Posted by igzy
My old ring expanded after I removed it and I had trouble putting it back in place so if you don't mind spending a few $$ extra I would recommend getting a new one...
08-11-2005, 03:06 PM
#97
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Originally Posted by igzy
Dude, filter is a filter. The purpose of it is to take crap out of the fuel
right... but theres a small fraction of fuel flowing through this filter as opposed to a return fuel system. per nissan it should outlast the pump. i wouldnt change it unless i had a measured fuel pressure drop under accel. if it makes you sleep better at night, then go ahead... i dont have a problem with it. i just wont be changing mine when i get my 5.5gen.
08-11-2005, 05:13 PM
#98
Originally Posted by BewstAdd1ct
right... but theres a small fraction of fuel flowing through this filter as opposed to a return fuel system. per nissan it should outlast the pump. i wouldnt change it unless i had a measured fuel pressure drop under accel. if it makes you sleep better at night, then go ahead... i dont have a problem with it. i just wont be changing mine when i get my 5.5gen.
Like I said, to me that is a filter and I wanted to change it and I did... Judging by the response in this thread it seems that many people share my opinion and it is meant to help them change it with least trouble... If you don't want to change it - then don't, no one is asking you to...
08-12-2005, 07:18 PM
#100
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Originally Posted by igzy
Oh, so you don't even have a 5th gen... How would you have a problem with it then? ;-)
Like I said, to me that is a filter and I wanted to change it and I did... Judging by the response in this thread it seems that many people share my opinion
and also consider... a filter that 'looks dirty', isnt necessarily causing a restriction.
08-12-2005, 07:44 PM
#101
Originally Posted by BewstAdd1ct
being an ASE master technician, i HAVE to provide sound advice to those seeking it
yes, either that or they were misinformed/misguided, but well meaning. when you say 'fuel filter', everyone thinks 'maintenance item', but in this case its not. so as soon as you provide a 'how-to' on changing the fuel filter, EVERYONE thinks 'jeez... i can remember ever doing that. it must be about time'
and also consider... a filter that 'looks dirty', isnt necessarily causing a restriction.
yes, either that or they were misinformed/misguided, but well meaning. when you say 'fuel filter', everyone thinks 'maintenance item', but in this case its not. so as soon as you provide a 'how-to' on changing the fuel filter, EVERYONE thinks 'jeez... i can remember ever doing that. it must be about time'
and also consider... a filter that 'looks dirty', isnt necessarily causing a restriction.
08-12-2005, 08:04 PM
#102
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im not saying a filter cant cause a restriction, and im not saying that your fuel filter is immune to being clogged. im just saying it shouldnt be replaced unless you have a measured fuel pressure drop under accel and that the filter should outlast the pump.
if you want to hold someone responsible, take it to nissan, ask them if it needs to be changed, when they say it doesnt, get it in writing
in fact, if something messes up from you not changing your filter, and the nissan svc manual says you dont have to change the filter, and your OWNERS manual mentions no fuel filter change interval, then if something breaks, its probably not the fuel filter at fault
if you want to hold someone responsible, take it to nissan, ask them if it needs to be changed, when they say it doesnt, get it in writing
in fact, if something messes up from you not changing your filter, and the nissan svc manual says you dont have to change the filter, and your OWNERS manual mentions no fuel filter change interval, then if something breaks, its probably not the fuel filter at fault
08-13-2005, 09:24 AM
#103
Filter most likely won't cause problems in the filter itself, fuel will get through one way or the other... But, the crap will get through and polute the injectors and may cause the lower pressure at the engine which most people cannot measure anyway... Or will blow the pump due to back pressure caused by the clogged filter... So either way I think it is a good preventative to save the pump or the injectors... I noticed a better response from the car when I changed it so something was clogged along the way...
08-13-2005, 10:02 AM
#105
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Originally Posted by igzy
Filter most likely won't cause problems in the filter itself, fuel will get through one way or the other... But, the crap will get through and polute the injectors and may cause the lower pressure at the engine which most people cannot measure anyway
nothing larger than what was designed to get through the filter will get through, unless the filter is torn, not sealing or otherwise damaged. nothing is going to get through. normal properties of the fuel causes clogged injectors, and thats fixed with an injector flush, not replacing the fuel filter
oh, and the pressure is regulated before the filter, AFAIK, so a clogged filter cant blow the pump
08-13-2005, 05:41 PM
#106
Do you know how long do you think a filter can last before it gets torn? Do you know how long it will last before fuel supply becomes a problem (or the lack of thereof)? I had a problem at 70K... I do not believe in "good for life filters"...
Could you explain these "normal properties of fuel" that clogg the injectors other than crap in fuel that is supposed to be taken out by filter?
Whatever, look I am not going to get into a p-ing contest here with you... I wanted to change my filter and I did with the help of this thread... I am just trying to assist other people who want to change it too and I am not here to convince people like you to change it... I have my beliefs and you have yours... Peace...
Could you explain these "normal properties of fuel" that clogg the injectors other than crap in fuel that is supposed to be taken out by filter?
Whatever, look I am not going to get into a p-ing contest here with you... I wanted to change my filter and I did with the help of this thread... I am just trying to assist other people who want to change it too and I am not here to convince people like you to change it... I have my beliefs and you have yours... Peace...
08-13-2005, 06:06 PM
#107
Originally Posted by BewstAdd1ct
in returnless systems, only the fuel that gets to the engine goes through the filter, which makes the filter life usually longer than the pump itself.
if you douchebags wanna tell me i dont know what im talking about, then feel free to replace you fuel filters, spend the extra money, waste your time. its a rare occasion that a filter in a returnless system causes a problem.
if you douchebags wanna tell me i dont know what im talking about, then feel free to replace you fuel filters, spend the extra money, waste your time. its a rare occasion that a filter in a returnless system causes a problem.
Besides, engineers aren't always good at practicality and every day use. Just because they designed the system to last the life of the car doesn't mean it really does. If you don't want to change out a filter that is your business and the problem of your customers because you forced them to drive around with dirty filters.
08-13-2005, 06:11 PM
#108
Originally Posted by BewstAdd1ct
oh, and the pressure is regulated before the filter, AFAIK, so a clogged filter cant blow the pump
Wrong, the pressure is reguated AFTER the filter. And a clogged filter can kill a pump by causing it to spin faster, overheat and wear out the brushes faster.
Perhaps if you had ever taken the time to look at one for yourself you would know this.
Page FE-6 in the 2002 Maxima ESM clearly shows the FPR as being mounted on the exit of the filter.
08-14-2005, 08:59 AM
#109
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Originally Posted by igzy
Do you know how long do you think a filter can last before it gets torn?
Do you know how long it will last before fuel supply becomes a problem (or the lack of thereof)?
I had a problem at 70K... I do not believe in "good for life filters"...
Could you explain these "normal properties of fuel" that clogg the injectors other than crap in fuel that is supposed to be taken out by filter?
Whatever, look I am not going to get into a p-ing contest here with you...
..you didnt think this was a pissing contest, did you?
I wanted to change my filter and I did with the help of this thread... I am just trying to assist other people who want to change it too and I am not here to convince people like you to change it...
08-14-2005, 09:11 AM
#110
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Originally Posted by SR20DEN
uhh ok... You don't know what you're talking about. ALL of the fuel that exits the fuel pump goes through the fuel filter. It DOES get recirculated dozens of times because the integrated FPR only vents AFTER the fuel has aready been filtered.
Besides, engineers aren't always good at practicality and every day use. Just because they designed the system to last the life of the car doesn't mean it really does.
If you don't want to change out a filter that is your business and the problem of your customers because you forced them to drive around with dirty filters.
...and im not forcing anyone to drive around like anything. if someone brought me a maxima, asked me to change the fuel filter, id explain the system to them. if the still insisted on having it changed, id do it for them... no problem.
08-14-2005, 09:17 AM
#111
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Originally Posted by SR20DEN
Page FE-6 in the 2002 Maxima ESM clearly shows the FPR as being mounted on the exit of the filter.
lol... post a pic. if its the same pic from the same manual that i have in front of me, then yeah... it appears that its on the exit of the filter.
but if that were the case, they could have mounted on the single output nipple.
hmm... tell me, why DO they have two nipples on the exit of that filter?
ill tell you. one of them is for the fpr. it bypasses the filter, the correctly pressurized fuel exits the other side.
if its not like that, then its a BLATANT oversight on nissans part.
08-14-2005, 09:33 AM
#112
Originally Posted by BewstAdd1ct
that doesnt make sense, it goes against the entire concept of returnless fuel. one of the major ideas is to only filter the fuel that will be used immediately, and any given volum of fuel will onyl be filtered ONCE.
i wont be a problem until it causes a problem, and im okay with that because im following the MFGs instructions
...and im not forcing anyone to drive around like anything. if someone brought me a maxima, asked me to change the fuel filter, id explain the system to them. if the still insisted on having it changed, id do it for them... no problem.
08-14-2005, 09:35 AM
#113
Originally Posted by BewstAdd1ct
lol... post a pic. if its the same pic from the same manual that i have in front of me, then yeah... it appears that its on the exit of the filter.
but if that were the case, they could have mounted on the single output nipple.
hmm... tell me, why DO they have two nipples on the exit of that filter?
ill tell you. one of them is for the fpr. it bypasses the filter, the correctly pressurized fuel exits the other side.
if its not like that, then its a BLATANT oversight on nissans part.
but if that were the case, they could have mounted on the single output nipple.
hmm... tell me, why DO they have two nipples on the exit of that filter?
ill tell you. one of them is for the fpr. it bypasses the filter, the correctly pressurized fuel exits the other side.
if its not like that, then its a BLATANT oversight on nissans part.
08-14-2005, 10:48 AM
#114
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meh... maybe youre right. toss a used filter in a sealed bag and send it to me. PM me and ill give you my addy
right, some systems are mechanical, others are electrical. some cars with returnless systems do use a servicable filter.
this is true. this also applies to a few fords, explorers for example. the regulator is actually inside the filter, and sends the excess volume back to the tank before filtering it.
the regulator is close to the engine because BMW still uses a vacuum signal for load to the variable fuel pressure regulator.
yes, in order to use a conventional vacumm based fuel pressure regulator.
what page of the BMW service manual is this stuff on, more specifically about the fuel being filtered and THEN sent back to the tank.
it pays 1 hour. as easy as everone whos done it makes it seem, ill take the gravy, IF the customer insists.
again, a filter that appears dirty doesnt indicate that its creating a restriction.
and regardless, the owners manual doesnt specify a change interval, svc info says it doesnt need to be replaced as a maintenance issue.
Originally Posted by SR20DEN
The concept of a returnless fuel system is not that complicated. It's only supposed to mean that fuel does not circulate through the fuel rail and back to the fuel tank.
Other manufacturers, such as BMW, don't use the Nissan model of having the FPR in the fuel tank.
BMW puts the fuel filter and attached FPR under the vehicle and pretty close to the firewall. Their system, like Nissans, does not return fuel to the tank that hasn't been filtered.
But like any 'returnless' system it does not circulate fuel through the fuel rail. Their design has certain fuel supply advantages that the Nissan design doesn't have.
what page of the BMW service manual is this stuff on, more specifically about the fuel being filtered and THEN sent back to the tank.
Only because the flatrate probably isn't worth your time. If you weren't on flatrate you would take this cakewalk job and be happy.
If you don't fully understand the system then you're giving them bad info. Find a A33x that has 50-60k miles on it and crack one open for yourself. It should become pretty clear at that point, Dirty **** filter = put in a clean filter. And FYI, I kinda thought the changing this part was a waste of time too. Untill sloppymax hired me to change his.
and regardless, the owners manual doesnt specify a change interval, svc info says it doesnt need to be replaced as a maintenance issue.
08-14-2005, 10:52 AM
#115
The BMW returnless systems I have referenced are not vacuum operated. I have never seen any factory returnless systems that were.
I don't have access to the BMW TIS that would show this. I only know it from personal experience. A good example to look at is the X5.
I don't have access to the BMW TIS that would show this. I only know it from personal experience. A good example to look at is the X5.
08-14-2005, 10:56 AM
#117
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heres an excerpt:
again, 03 330Ci
Disconnect vacuum hose from fuel pressure regulator and measure fuel pressure.
The measured value must increase by 0.4 to 0.7 bar depending on the engine. Note down measured value.
If the measured value does not increase: Replace vacuum hose and measure fuel pressure again
If the measured value still does not increase; Replace pressure regulator
Measure fuel pressure again and note down measured value.
Compare the measured value with the nominal value stamped in the pressure regulator housing.
If the specified measured value is still not achieved, you must carry out the following checks depending on the measured value.
...
The measured value must increase by 0.4 to 0.7 bar depending on the engine. Note down measured value.
If the measured value does not increase: Replace vacuum hose and measure fuel pressure again
If the measured value still does not increase; Replace pressure regulator
Measure fuel pressure again and note down measured value.
Compare the measured value with the nominal value stamped in the pressure regulator housing.
If the specified measured value is still not achieved, you must carry out the following checks depending on the measured value.
...
08-14-2005, 10:56 AM
#118
Originally Posted by BewstAdd1ct
you didnt specifically point out a make or model, so lets start there.
i was referring to the 330ci
i was referring to the 330ci
