Fuel consumption up after fitting EGR blanking kit

[Roverlord off road spares]

L322 3.0
I noticed that my fuel consumption has gone up slightly since removing my EGR and fitting the blanking unit.
I used to return 10.8-10.9 litres per 100kms not it's 11.4 litres per 100 kms.
I ran diagnostics on her and got this code
P0401-20 extended fault path exhaust gas recirculation governor deviation - negative deviation.

After having a chat with GAP, I was informed the likely cause of the fault would probably be an air leak.
Today I had to removed the intake inter-cooler hose to access the radiator bleed screw to do a coolant change. Whilst I had the inter cooler hose off , I pulled the EGR blanking replacement unit off and ran a small bead of RTV around the mating to intake surfaces. Just to eliminate that. I don't think that was the cause though.
I checked the inter cooler hose no evidence of a leak there.
I did notice the bottom hose was pretty soft at the bend. so will replace that on Friday.
( Just be the way what a stupid setup up on the hose connection, a jubilee clamp to fit hose to a tin connector and then that tin connector connects to the inter cooler with some rubber seal lip inside and a spring clip to retain it. Why didn't they just put a lip on the outlet of the inter cooler and the hose just clamp directly to that , but oh no, over engineering, complicating things unnecessarily. And you can't buy that tin connector separately, it only comes with the hose, which now can't be bought separately, it supersedes to an assembly with hose /pipe and upper hose connected. I am replacing it with original as the tin connector is not firm when connected, the inner seals are worn. some leak of oil apparent, so not sealing well. Otherwise I would have put a silicon hose on and used the existing connector .)

I now wonder if a partially collapsing inter cooler hose restricting air intake has slightly increased the fuel usage?
Eliminate a dirty air filter as I recently replaced it.

Any suggestions? Cheers, Mario

[peter g]

Hi Mario,
On one of my regular journeys (in now sold TD6) I would consistently get 10.5 L/100 before fitting the EGR Blanking, after fitting this went to 10.1-10.2. so economy improved.
cheers, Peter

[Roverlord off road spares]

Hi Mario,
On one of my regular journeys (in now sold TD6) I would consistently get 10.5 L/100 before fitting the EGR Blanking, after fitting this went to 10.1-10.2. so economy improved.
cheers, Peter Hmm interesting, so there is something causing it. it's only .5 of a litre more , but it equates to nearly 5 litres over a tank.
I did some more googling and it brought up an old post on AULRO, http://www.aulro.com/afvb/technical-chatter/238599-fault-code-p0401-20-a.html
Cause: a leak from a split vacuum hose from the EGR ( the Grey one with the Blue strip ) had a split. I have examined this hose on mine at the EGR end and it looks ok, but cant seem to find the other end of it as it disappears on the side of the passenger side of engine, it's pretty hard to get to, so it might be removing the top engine cover to give some more light to it. It is the only hose that was disturbed when I pulled it off the EGR, maybe the removing caused the hose to split somewhere along it's length.
Cheers, Mario

[Roverlord off road spares]

I tried something today, I disconnected the battery for 10 mins , then joined the disconnected POS & NEG leads together for 10 mins, I read that doing this resets the ECU .
So after 10mions I reconnected the battery and and took her fro a drive.
Immediately I got a fuel consumption reading of 26.1 litres per 100 kms.! :o but as I drove it started to come down, it got as low as 7.5 litres per 100 kph. I drove for 40 kms and it strated to move to 8.5 then to 9 and settled at 9.5 - 9.9 for most of the journey, acceleration up steep hills increased it to 10.1 litres per 100kms, so I was very happy. but now it's creeping back up to and sitting 11.1 litres per 100 kms, so I'm at a loss.
I can't find a suspected vacuum leak anywhere, so at a loss.


The only error code is that P0401-20 extended fault path exhaust gas recirculation governor deviation - negative deviation. which has me stumped.

Interccooler to intake hoses are replaced so no leak there. Vacuum hoses all hold suction so no leaks there.

PS, just went for another drive and fuel consumption has dropped again., it's now around 10.3 around town, I noticed this relates to lower ambient temperature, temp was 17.5C, earlier on when the Ambient temp was up around 26c the fuel consumption was higher. co incidence?

[rar110]

It might be time to flush out the intercooler.

[Roverlord off road spares]

It might be time to flush out the inter cooler.
Would a gunked up inter cooler cause these symptoms?

[rar110]

If it's running better cold then maybe. I presume on the td6 oil vapour enters the turbo intake and then travels with clean air through the intercooler. If the crank case ventilation filter isn't working well there could be extra oil in the ventilated air.

[Graeme]

Fuel consumption will always go higher as ambient temperature increases providing the engine is at operating temperature, ie has warmed-up. Cooler air is denser so provides more oxygen for more efficient combustion.

[Roverlord off road spares]

If the crank case ventilation filter isn't working well there could be extra oil in the ventilated air.
The Crank case filter has replaced by the later modified cyclonic filter, so clogged filters are out of the equasion

[rar110]

Maybe try an induction cleaner such as Revive. It's to clean build up in the turbo, intercooler, and intake manifold to some extent. I've used it on the tdv8. The motor ran noticeably smoother after, not that it was running rough. My L322 had about 240,000 on it when I had the Revive treatment done.

[Roverlord off road spares]

Maybe try an induction cleaner such as Revive. It's to clean build up in the turbo, intercooler, and intake manifold to some extent. I've used it on the tdv8. The motor ran noticeably smoother after, not that it was running rough. My L322 had about 240,000 on it when I had the Revive treatment done. When I removed the egr ir was suprisingly clean in there, The turbo had been replace by previous owner and I assume other work done.

I was just thinking , I put the later modified crank case filter in, around the same time I put the EGR blanker in, I might remove it and refit the original filter type one back in and see if it makes any difference.
As the code that comes up might have something to do with the breathing?
It wasn't a genuine BMW part but one I purchased from a seller in the UK, so probably a Chinese copy maybe these copies aren't up to spec and is causing the code I got?

[RangieBit]

G'day,

The fault code (P0401) you are getting is most likely due to the fact that you no longer have a vacuum regulator valve to control the flow of exhaust gasses. This means no feedback to indicate how much or little deflection, and thus how much exhaust gas, is being fed into the induction system. Is the loom connector from the EGR attached to anything anymore? Is the vacuum line connected to a valve? If not, this is the most likely source of your fault code.

Good to hear that the induction path was clean, this will definitely help.

I gained about 0.5-1 l/100km around town and about 2l/100km average highway after fitting the blanking kit. Like all things automotive your consumption may vary.

Cheers,
Iain

[Roverlord off road spares]

G'day,

The fault code (P0401) you are getting is most likely due to the fact that you no longer have a vacuum regulator valve to control the flow of exhaust gasses. This means no feedback to indicate how much or little deflection, and thus how much exhaust gas, is being fed into the induction system. Is the loom connector from the EGR attached to anything anymore? Is the vacuum line connected to a valve? If not, this is the most likely source of your fault code.

Good to hear that the induction path was clean, this will definitely help.

I gained about 0.5-1 l/100km around town and about 2l/100km average highway after fitting the blanking kit. Like all things automotive your consumption may vary.

Cheers,
Iain
Hi Ian, this is the blanking kit.
you will see I have marked where things connect.
The thin rod is solid, and is welded onto the blanker just so you have somewhere to attached the existing vacuum hose from the Vacuum modulator to. ( the Vacuum modulator is situated about 1/2 way along the passenger side of the engine, it has a wiring connector attached to it, none of this has been touched.

So when removing the factory EGR all you do pull off the vacuum hose and then fit it to the rod on the side of the EGR blanker, nothing else is touched. you then hook up the inter cooler hose and the existing exhaust hose is clamped on to the blanker, which is solid, so that blanks it off.
117611

So the whole system is still as it was except the vacuum hose is plugged so it just applies vacuum to the blank rod and has nothing to suck anymore.

[DiscoMick]

I could be wrong about this, but I think I read somewhere that the blank needs to have a small hole in the centre to allow air pressure to equalise. Not sure if that applies to yours. Just a thought...

Sent from my A1601 using AULRO mobile app

[Roverlord off road spares]

I could be wrong about this, but I think I read somewhere that the blank needs to have a small hole in the centre to allow air pressure to equalise. Not sure if that applies to yours. Just a thought...

Sent from my A1601 using AULRO mobile app
I think I saw that somewhere also. I put the iitool on it again yesterday, and another code came up.
P0314-01 Cylinder balance control - I-component deviation outside limit - General failure information - general electrical failure

I notice at idle the dash gauge needle slightly bounces ever so slightly, the iidtool shows idle bounces 20 -30 rpms , so not as smooth as before , so maybe one of the injectors is over fueling ?
No smoke out the exhaust though . I did replace the injector loom so it cant be the loom causing electrical problems. I have been using chemtech diesel additive over a few tank fulls. I wonder if this is gunking up the injectors with what it supposed to clean?
Maybe all this intial stuff was a co incidence and it is the injector fueling causing this.
I don't know how to decipher the CYL Compensation info from the ID tool.

[Judo]

Hi Mario, I had the same cylinder balance fault when I first did a read with my IID. I cleared all faults and I've done a few hundred kms since then and it hasn't come back. I had a lot of other faults that haven't come back too - a lot of them were low voltage faults so possibly battery/power related?

[Roverlord off road spares]

Hi Mario, I had the same cylinder balance fault when I first did a read with my IID. I cleared all faults and I've done a few hundred kms since then and it hasn't come back. I had a lot of other faults that haven't come back too - a lot of them were low voltage faults so possibly battery/power related?
Hi Justin, it has a brand new battery.
I have attached graph from iidtool, number number 1 is up and down and 6 cylinder is not running very smooth according to graph
117655

Fuel Comp readings are as follows.
Cyl 1 655 mm3
Cyl 2 654 mm3
Cyl 3 655 mm3
Cyl 4 653 mm3
Cyl 5 653 mm3
Cyl 6 6 mm3

I took the plug off injector 1 and 6cyl individually and the engine stumbles, I can also feel them actuating with the wire reconnected.

As I said I don't know how to interpret this info, but something is wrong.
Cheers, Mario

[chaybra]

Hi Justin, it has a brand new battery.
I have attached graph from iidtool, number number 1 is up and down and 6 cylinder is not running very smooth according to graph
117655

Fuel Comp readings are as follows.
Cyl 1 655 mm3
Cyl 2 654 mm3
Cyl 3 655 mm3
Cyl 4 653 mm3
Cyl 5 653 mm3
Cyl 6 6 mm3

I took the plug off injector 1 and 6cyl individually and the engine stumbles, I can also feel them actuating with the wire reconnected.

As I said I don't know how to interpret this info, but something is wrong.
Cheers, Mario


This recently happened to mine,however no fault was thrown. just a pulsing idle that i could feel at crawling speeds.
changed the injector with a second hand one and back to normal. my numbers still move around a bit.

[BigJon]

QUOTE=Roverlord off road spares;2616945]L322 3.0


( Just be the way what a stupid setup up on the hose connection, a jubilee clamp to fit hose to a tin connector and then that tin connector connects to the inter cooler with some rubber seal lip inside and a spring clip to retain it. Why didn't they just put a lip on the outlet of the inter cooler and the hose just clamp directly to that , but oh no, over engineering, complicating things unnecessarily. And you can't buy that tin connector separately, it only comes with the hose, which now can't be bought separately, it supersedes to an assembly with hose /pipe and upper hose connected. I am replacing it with original as the tin connector is not firm when connected, the inner seals are worn. some leak of oil apparent, so not sealing well. Otherwise I would have put a silicon hose on and used the existing connector .)

[/QUOTE]

This is one of the major L322 draw backs. Engineering by BMW. I have long stated that when it comes to car design there is the easy way, the hard way and the BMW way. The BMW way makes the hard way look easy!

[Roverlord off road spares]

Lastest update, I poured a can of Liqui-Moly diesel fuel injector cleaner in, drove to the airport and back and my fuel consumption has dropped from 11.9 litre per 100kms down to 10.6, so it must be a dirty injector. Also the idle is getting smoother, so touch wood this stuff is the answer.

[MRMEENER]

If you think injector 6 is iffy why not swap 5 and 6 to see if the problem moves. You can also take the Injector nozzle off easily and if you squirt brake cleaner through it at aerosol can pressure there should be 5 clear spray patterns, less will mean blockages. The holes are microscopic but they will clear if you are lucky by soaking in brake cleaner.https://www.aulro.com/afvb/images/imported/2016/12/219.jpg