[DIY] Created an inline fuel filter - Will that solve the injector issue?

[jvictormp]

Originally Posted by Veracity

Of course there will not be an issue upstream, it’s a low pressure sensor. If the filter get clogged it will never read low.

Also NRW uses Aeromotive fuel filters in their kit. Aeromotive releases all their tech data about their products online and free. There is a reason the filter has to be a certain size. I’d trust Aeromotive over someone trying to make something just because it fits better.

In theory, by keeping it upstream you can have a lean-mixture issue, without having any low pressure fault. That's the issue itself.

I'm certain that NRW/Aeromotive has the best option.

[Veracity]

Originally Posted by jvictormp

In theory, by keeping it upstream you can have a lean-mixture issue, without having any low pressure fault. That's the issue itself.

I'm certain that NRW/Aeromotive has the better option.

That sensor does not detect lean issues, only low pressure

[jvictormp]

Originally Posted by Veracity

That sensor does not detect lean issues, only low pressure

That's what I said.

[Assimilator1]

I'm not really understanding what either of you are saying about the fuel pressure sensor.

Originally Posted by Veracity

Of course there will not be an issue upstream, it’s a low pressure sensor. If the filter get clogged it will never read low.

.....

jvictormp on 10-1 said the sensor has been moved downstream (presumably after the filter, relative to flow), but you said upstream, I guess you mis-read his post?
If the sensor is after the fuel filter (downstream), and the filter were to get blocked, then the low pressure sensor will trigger a fault code.

Originally Posted by jvictormp

Great move!

Only observation I could make is: those "bolt/nut" style hose clamps (not the worm type, the other one).

You should inspect it often, because when I used it here, it tended to get loose overtime and begin dripping. Don't know why. It even disconnected the hose once . I ended up moving to PTFE AN Fittings. I could make a video of how to install the fitting in the hose if you want.

But I don't see a risk there because it's far from exhaust and you'll feel the smell before it gets severe.

The 'nut and bolt' clip is a proper fuel clip and will grip the hose evenly, it's more dubious to use jubilee clips (the worm drive ones), especially if they're wound to very near their minimum size.
What happens is that jubilee clips form an oval shape instead of a round shape when wound right in (or near to). This means the parts of the hose at the ends of the oval shape aren't clamped as tightly and could leak after a while.

With either type clip fitted to a new hose you are likely to need to tighten them again, say 6-12 months later if they weren't quite tightened enough in the 1st place. Especially in the 1st year the new rubber loses some of its 'springyness', hence what seemed tight enough, later isn't.
This is one reason why manufacturers like to use spring clips, as they keep a constant pressure on the hose as it shrinks and hardens.

Btw "feel the smell"? I think you meant smell the fuel , but either way, you don't want to find a leak by relying on smelling it, it'll be pretty bad by then!

[andrihallik]

After almost a year the inline e36 m3 filter has been tested.

Did one long trip to alps and 2 ~1h session track days in warm weather. And lots of backroad driving.
In total ~10k km.

Few months ago changed the filter and opened up the old one - no debris at all.
Few small black pits but probably came when opened the filter up.

For the clip experts, both clips were nice and tight No leaks at all

Also Inpa and Ista didnt give any codes.

[Assimilator1]

That old fuel filter appears to be pristine , no surprise given the low mileage.
You could likely triple the mileage until the next change, and I'd bet it'd still be fine.

Have you got that inline filter in addition to the tank one?

[Assimilator1]

Thought I'd mention here an idea I had about an alternative DIY fuel filter instal, but more like the OEM version fitted to Chinese M3s.

Firstly, has anyone got access to the Chinese BMW parts catalogue? That would make things a whole lot easier! I don't see it in realoem, but I don't have a Chinese VIN.
Anyway, after someone mentioned the OEM fuel filter for the Chinese M3's in the m3cutters forum, someone else mentioned it looked quite similar to the diesel version.
So I wonder if we can recreate the OEM fuel filter instal using the diesel's pipes connected to the Chinese OEM petrol filter? (assuming we can't find the part nos for the Chinese petrol pipes etc).
But lots of questions, like would the pipes fit? (to the filter, the tank, or the rail?). Also, where is the low pressure sensor fitted?

Here's a couple of pics of the fuel filter on e90 330d - https://photos.app.goo.gl/sw1tfbUG7jYnEAKu9 - https://photos.app.goo.gl/gfVbdxFDC7JrJ5n9A
At some point, I'll put my 330d and M3 on adjacent lifts and see if I can see what might fit. But if anyone knows something about that already, I'm all ears!

Btw, as for pre-made kits, I think EAE is the best looking, but that or the NRW are bloody expensive for what they are!

[andrihallik]

Originally Posted by Assimilator1

That old fuel filter appears to be pristine , no surprise given the low mileage.
You could likely triple the mileage until the next change, and I'd bet it'd still be fine.

Have you got that inline filter in addition to the tank one?

Yes still have the filter inside the tank.
Dont remember now but the one inside the tank is somewhere 50 microns and removing it will probably cause error codes

[Assimilator1]

Originally Posted by andrihallik

Yes still have the filter inside the tank.
Dont remember now but the one inside the tank is somewhere 50 microns and removing it will probably cause error codes

Thanks, btw I saw in your 1st post here you asked about the Chinese market OEM inline filter. I posted this message to the m3 cutters injector thread.

I've been looking into whether this is feasible to re-create.
As far as I can tell (using realoem and the above filter's part No), even in China this was not an option for the M3 (at least with this filter).
It was however fitted to the regular e9x's there and to the 1M (which shares much of the e9x M3's platform).

Here's the realoem links if anyone's interested :-

China 335i (M3s not listed for that filter) - https://www.realoem.com/bmw/enUS/sho...46#16127451424
China e82 1M inline fuel filter - https://www.realoem.com/bmw/enUS/sho...46#16127451424

Looking at the parts there (& the above diagram from kevinm) they have an extra fuel line (a return line), and it appears to return to the pump, a photo on realoem shows 2 pipe connections, presumably our M3's pumps don't? If so, replacing a pump to achieve this would just make it pointlessly expensive!

So next I'm going to look at a hybrid setup, a simple 2 outlet inline fuel filter underneath (in the same position as above, using that bracket) and splice in the fuel filter or get some fuel lines made up.

************************************************** ***************************

So it looks like I might well be doing a similar thing to you, although my plan is to use the OEM bracket, rather than making one. Hopefully the captive nut is there for the bracket's bolt, if not I'll buy a thread insert.

[Assimilator1]

Originally Posted by andrihallik

Recently installed e36 m3 inline filter on my 2008 dct e92 m3.
Have done 4-5 tanks now with some spirited backroad driving and with some high rpm winter fun.

Have not yet checked the fuel pressure or condition of spark plugs but overall cant see, feel or hear anything different - will update in few months when the weather is warm and track is dry.

As the filter is located before the fuel pressure sensor i doubt that there are any issues. Seems like the Chinese market e9x m3 has same kind of filter in same location.

Also was not feeling confident about installing fuel filter right above the veeery hot exhaust manifolds.

In total ~5cm of the original fuel line was cut off so that the original fuel line holder brackets can still be used. Also after cutting the line its not hard to clean lines from debris - can access the line from engine side and from tank side can just turn the ignition on and fuel pump blows the remaining debris out. Also flanged the fuel lines - that required hydraulic flange tool .. PITA.

Made simple aluminium bracket - didnt want to cut holes into the cars frame so used the original underside panel holder hole for one side (underside panel didnt have hole for it) and other is just aluminium sheet turned into U shape, added some rubber protection for the aluminium bracket and also fuel filter so there will be no metal to metal contact. The filter is fixed and super solid - no movement at all and with underside panel on cant see anything.

Todo: 3d printed bracket for fuel filter, replace rubber fuel line with braided and use AN fittings? or something more solid - nothing leaking but before going to track just want to be sure.
- does anyone have picture from underside of the Chinese markets car? There is probably part number for the original bracket

Sorry for ugly pics - car is extensively covered and filled with Dinitrol ML.

How did you flange plastic pipes?? lol
Btw, am I right in what I think I see, 1 of the OEM pipes is plastic, the other steel?

[Assimilator1]

andrihallik
As well as my above questions, do you (or anyone) know what size is the fuel line from the tank to rail? Item 1 here.

Btw, this is the OEM inline fuel filter bracket, it's not fitted to any M3 version I could see, but used on various e9x's, both petrol and diesel. Part No 13328513540
There's a better picture of it here.

Protection plate, for filter? 16127174891(e9x, petrols & most diesels except e90/91 N57)

[Assimilator1]

Answering my own questions, the fuel line is 8mm diameter and it is probably made from stainless steel (seemed too hard for aluminium), which probably explains why andrihallik had difficulty flaring it (could you confirm that?).

Btw, here are some part number for the fuel filter fitted to the M3 e36 (3 ltr euro, all US versions) - BMW 13321740985, Bosch (F5905) 0450905905, Mahle KL 66, Valeo 58714, Mann WK 516/1. 300mm long, 55mm diameter, 8mm pipes.
That is big enough btw, as the M3 F80 chinese version is fitted with a 250mm long, 55mm diameter fuel filter (Mann WK 6030).

Looks like I'll be nearly copying andrihallik's setup, except I'm going to try to use the OEM fuel filter bracket (BMW part no 13328513540).
The protection plate fitted to diesels and chinese petrol versions isn't need, nor can be fitted to our M3s.

[Assimilator1]

Originally Posted by andrihallik

Yes still have the filter inside the tank.
Don't remember now but the one inside the tank is somewhere 50 microns and removing it will probably cause error codes

Could you answer my question above?

[andrihallik]

Originally Posted by Assimilator1

Could you answer my question above?

Sorry! For some reason did not get any email notifications from m3post.
Did you already install it? How did the bracket fit?

25k km later now - after replacing the filter once i did not tighten the hose on the fuel filter enough and it was little bit wet - instantly smelled the petrol. So if it leaks even little bit u will smell it quickly Otherwise no issues at all!

I did not touch plastic lines at all. There is only one stainless steel fuel line from which i cut out like ~5cm. Flared both sides - bought some general brake line flaring tool which did not work, later rented bigger one. Flared both ends so the fuel hose would hold on stronger. As it is not high pressure i think it might work without flaring also. As i use 2 clamps on both sides i pushed the fuel hose on for quite a long way. The e36 m3 filter is turned another way around because that way the fuel hoses route better - no hard bends etc.

For the plastic line - do you mean fuel return line? The plastic line underneath should be fuel tank breather line that comes from the air intake plenum and goes to tank. This is irrelevant.

The m3 e36 filter is inline so there is no separate return line. I used 13321405092, BOSCH 0 450 905 942
The petrol models of e9x chassis has returnless fuel system, there is fuel pressure regulator inside the fuel pump additionally to the one in engine pay so no unused fuel is sent to the engine.

Thank you so much for the bracket code 13328513540
I think it will not mount to the hole that is meant for the underside plastic where i attached my diy bracket.
Might have to bend it little bit or diy some extension bracket. There is no other place where this might attach.

As i located the filter right next to the pinch weld/seam below the car i dont think any protection plate is needed.
The pinch seam is little bit higher than the fuel filter and the underside plastic is quite strong.
I think the protection plate wont help much.. unless you go offroading


Also heard from one race mechanic that has prepared few e9x chassis cars for BATCC does this same thing on all his e9x because he messes with fuel tanks and lines all the time and does not want any debris to get to the injectors.

BTW recently replaced injectors - they are 30% cheaper atm, instead of usual 65€ they are around 44€ atm. (not fake bosch, checked every one via the bosch keysecure)
They were pretty gunked up at 225k km but fuel consumption fell little bit - its an investment
Available here for example - https://www.ak24parts.com/en/sparepa...-0-280-158-164 (not sure if they ship outside of europe)

[PapaMurph]

It appears that you have a bit of an oil leak going on down there

[andrihallik]

Originally Posted by PapaMurph

It appears that you have a bit of an oil leak going on down there

You know that cars that leak oil dont rust?
Dinitrol ML - usually used for cavity but i do this on the underside aswell whenever i plan to drive in the winter. Looks nasty and makes working on the car dirty but next owner will be happy af

[Assimilator1]

I mentioned in my last post here that the protection plate couldn't be used on the M3s . They are fitted to the diesels though, up front of the floor, the M3s have a crossmember or part of the subframe there.

Yes I used an extension plate to attach the BMW bracket to the floor bracket, I also had to slightly straighten out the bracket to get the right angle.

I would strongly advise anyone against fitting hoses to unflared fuel pipes. From what I gathered they can creep off over time, additionally I don't recall ever seeing a manufacturer do that.

I was unable to hire a flarer capable of doing stainless steel pipe, nor did I want to remove the fuel pipe and take it to somewhere that could, lots of hassle and time! Compression fittings along with hosetail fittings did the job nicely . Several hundred miles on and it's holding just fine

The petrol models of e9x chassis has returnless fuel system, there is fuel pressure regulator inside the fuel pump....

This only applies to the M3, the other petrol versions have a regulator in the fuel filter(!), hence 3 pipe connections. This was where I was getting confused, and yea later I realised it was just a vapour line.

Also I've answered your other questions in my DIY fuel filter thread.

Thanks for eventually getting back to me anyway