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K
krunchi
Guest
Alrighty i think i know what is causing this now!
It is EGR related but thats only part of it.
Blocking of EGR stops the exhaust gas going into the intake but at that same time the ECU starts to close the butter fly to sheild the intake air so that the engine will consume the EGR air.
Its the movement of this Butterfly that causes the compressor surge/turbo flutter while on lite load.
This butterfly can be seen before the EGR port on the manifold.
Turns out som VW TDIs have the smae problem and thats the issue.
Some of the VW guys have fixed it with puggy back cpmuters that let them turn down the EGR.
Doing this via the ECU also turns down the function of the associated Butterfly in the intake.
No think i know the cause, the challenge now is how can i 'turn down' EGR so that the whole system is limited, Remember blocking it doesnt fix the associated Butterfly which is part of how the EGR works.
Cheers
It is EGR related but thats only part of it.
Blocking of EGR stops the exhaust gas going into the intake but at that same time the ECU starts to close the butter fly to sheild the intake air so that the engine will consume the EGR air.
Its the movement of this Butterfly that causes the compressor surge/turbo flutter while on lite load.
This butterfly can be seen before the EGR port on the manifold.
Turns out som VW TDIs have the smae problem and thats the issue.
Some of the VW guys have fixed it with puggy back cpmuters that let them turn down the EGR.
Doing this via the ECU also turns down the function of the associated Butterfly in the intake.
No think i know the cause, the challenge now is how can i 'turn down' EGR so that the whole system is limited, Remember blocking it doesnt fix the associated Butterfly which is part of how the EGR works.
Cheers
i would check the butterfly theory. hook a light or vac gauge on the actuator and see if it is used.
most of the variable turbo motors do not use a butterfly in the intake for the EGR. the variable turbo does the same job as the butterfly on a normal turbo motor.
most of the variable turbo motors do not use a butterfly in the intake for the EGR. the variable turbo does the same job as the butterfly on a normal turbo motor.
K
krunchi
Guest
Hey Tweak,
Thanks for the reply,
The D40 Nav has a Butter fly to limit air intake form the turbo.
After this Butterfly is the EGR Vavle, i had trouble explaining it in the above post.
Basically when teh EGR opens in light load the Intake Butter Fly closes to limit air intake from the turbo.
Now EGR and the butter fly dont initiate while in Neutral or Park so can be had to visually inspect it working.
Im thinking if i can limit the EGR and Buterfly working then maybe look at options of block EGR and keep that air intake Butterfly open.
Thanks for the reply,
The D40 Nav has a Butter fly to limit air intake form the turbo.
After this Butterfly is the EGR Vavle, i had trouble explaining it in the above post.
Basically when teh EGR opens in light load the Intake Butter Fly closes to limit air intake from the turbo.
Now EGR and the butter fly dont initiate while in Neutral or Park so can be had to visually inspect it working.
Im thinking if i can limit the EGR and Buterfly working then maybe look at options of block EGR and keep that air intake Butterfly open.
afaik the butterfly is only used for shutoff, not for egr purposes. so please check that it is actually used for EGR.
it may be the later ones have added that feature.
the other thing here is some engines close the butterfly when they overboost (ie to stop engine runaway), just another thing to check.
it may be the later ones have added that feature.
the other thing here is some engines close the butterfly when they overboost (ie to stop engine runaway), just another thing to check.
Chip Tuning
Member
Chip Tuning
Member
QUESTION
i think the butterfly that is meant here is NOT the main butterfly on the air intake but the butterfly on half of the EGR manifold.
CLICK HERE
Then, click on the Toyota EGR balnking guide thumbnail pic.
in the top right hand corner you will see the two butterflies I think is what is being referred to.
???
i think the butterfly that is meant here is NOT the main butterfly on the air intake but the butterfly on half of the EGR manifold.
CLICK HERE
Then, click on the Toyota EGR balnking guide thumbnail pic.
in the top right hand corner you will see the two butterflies I think is what is being referred to.
???
K
krunchi
Guest
Hey robert,
Thanks for the link, the Nav one works a bit different.
The actual Air intake butter fly is right where the pipe off the cooler conencts to the intake manifold. Thats the one that closes to slow down intake air when the ECU decides to swallow more EGR.
the actualy operation of that intake valve is yet to be confirmed however, i am told it is alwasy open and only closes when the engine is shut off. But another source tells me it varies its opening depending on EGR intake. So blocking EGR pipe will not have any effect on the movement/disruption this butterfly will cause.
As soon as i get that EGR block plate in post ill put it in and if it solves the flutter then its prob safe to assume that Butterfy in the intake has nothing to do with it
ChipIT
Does the ChipIt module give the ability to electronically limit or turn off the EGR operation?
Also if long term reliability is a top priority are there any ill effects of EGR block and the ChipIT install? Stuff like does it raise EGTs etc. Just trying to make a informed choise on it all. Cheers
Thanks for the link, the Nav one works a bit different.
The actual Air intake butter fly is right where the pipe off the cooler conencts to the intake manifold. Thats the one that closes to slow down intake air when the ECU decides to swallow more EGR.
the actualy operation of that intake valve is yet to be confirmed however, i am told it is alwasy open and only closes when the engine is shut off. But another source tells me it varies its opening depending on EGR intake. So blocking EGR pipe will not have any effect on the movement/disruption this butterfly will cause.
As soon as i get that EGR block plate in post ill put it in and if it solves the flutter then its prob safe to assume that Butterfy in the intake has nothing to do with it
ChipIT
Does the ChipIt module give the ability to electronically limit or turn off the EGR operation?
Also if long term reliability is a top priority are there any ill effects of EGR block and the ChipIT install? Stuff like does it raise EGTs etc. Just trying to make a informed choise on it all. Cheers
Hey Rob,
I have to sucomb to the fact it may be a cable, be it accelerrtor or clutch. Been busy so have not havd a chnce to take another look.
thats is an egr bypass valve. that lets egr bypass the egr cooler. i'm not sure but i think they open the bypass in very cold weather to help keep motor warm.
anyway navaras don't use a system like that.
actually easy way to check if intake butterfly is egr related, simply get someone to put vehicle in gear (foot on clutch!) and give it a few revs. if its EGR related you will see it partly shut when you rev it (use part throttle NOT full throttle).
K
krunchi
Guest
Tweak
I have a Auto, cant seem to replicate the fullter noise while in D with foot ont he brake and slight accelerator.
The VW TDI guys have piggy back modules that allow the detuneing of the EGR activity.
Sounds like a great way around it, but not currently avail for Navs.
All of this has sparked me to just get rid of all the crap i dont like so looking at possibly removing the DPF. That may also mean cheaper oil changes as i dont have to use that Enviro plus expensive oil as i dont have a DPF to clog.
I have a Auto, cant seem to replicate the fullter noise while in D with foot ont he brake and slight accelerator.
The VW TDI guys have piggy back modules that allow the detuneing of the EGR activity.
Sounds like a great way around it, but not currently avail for Navs.
All of this has sparked me to just get rid of all the crap i dont like so looking at possibly removing the DPF. That may also mean cheaper oil changes as i dont have to use that Enviro plus expensive oil as i dont have a DPF to clog.
don't listen for the noise, look for the butterfly closing. obviously you will need a helper.
afaik the UK guys can reprogram the D40 ecu's. what makes it tricky is nissan can update the programming, in which case you need to get it reprogrammed $$$$$.
fairly sure they can turn off the egr via programming.
Chip Tuning
Member
Hey robert,
Thanks for the link, the Nav one works a bit different.
The actual Air intake butter fly is right where the pipe off the cooler conencts to the intake manifold. Thats the one that closes to slow down intake air when the ECU decides to swallow more EGR.
the actualy operation of that intake valve is yet to be confirmed however, i am told it is alwasy open and only closes when the engine is shut off. But another source tells me it varies its opening depending on EGR intake. So blocking EGR pipe will not have any effect on the movement/disruption this butterfly will cause.
As soon as i get that EGR block plate in post ill put it in and if it solves the flutter then its prob safe to assume that Butterfy in the intake has nothing to do with it
ChipIT
Does the ChipIt module give the ability to electronically limit or turn off the EGR operation?
Also if long term reliability is a top priority are there any ill effects of EGR block and the ChipIT install? Stuff like does it raise EGTs etc. Just trying to make a informed choise on it all. Cheers
when you add a chip and its tuned correctly you actually bring the power on MUCH lower in the rev range.
by doing this your engine is not under more stress. if you can bring in the power earlier you wont have to rev the crap out of the engine to get it to go. Revs and heat kill engines. You can get HUGE numbers from an engine but don't increase the red line and it will last longer than engines that have their red line increased to get horsepower.
Chips can actually make your engine last longer because you are off the loud pedel when the revs are at the higher end. basically you get off the throttle early ... which also allows better fuel economy.
hope this helps
K
krunchi
Guest
Hey Guys,
Well EGR plate from ChipIT tested and guess what!!
No more flutter noise and no more jerking when the flutter noise comes in.
So why could i diagnose this with the assistance of forum members but nissan australia and the dealer could not!?
Must have something to do with either shit warranty or the fact it was a known issue with emmision control that they could not fix and still eb in line with the regulations?
Any way back to the ChipIT plate, it improved drivability and made the car much much smoother to drive, slightly more bottom end as well.
Thanks ChipIT and to all those who contributed in this thread.
Before we close of the thread all together i will test it for flutter and jerking on the highway this weekend
Well EGR plate from ChipIT tested and guess what!!
No more flutter noise and no more jerking when the flutter noise comes in.
So why could i diagnose this with the assistance of forum members but nissan australia and the dealer could not!?
Must have something to do with either shit warranty or the fact it was a known issue with emmision control that they could not fix and still eb in line with the regulations?
Any way back to the ChipIT plate, it improved drivability and made the car much much smoother to drive, slightly more bottom end as well.
Thanks ChipIT and to all those who contributed in this thread.
Before we close of the thread all together i will test it for flutter and jerking on the highway this weekend
Chip Tuning
Member
Hi Krunchi ... thanks for the positive feed back
and ... leave the thread open I say. There will be many with questions etc
and ... leave the thread open I say. There will be many with questions etc
I think there might still be an issue with the turbo - some others reported that it was a faulty unit and replacing that fixed it completely. If you still get some flutter, make sure you get back to Nissan and have the thing replaced - it's not supposed to do that!
K
krunchi
Guest
Hey Tony,
I have no idea how i am going to get nissan to fix it when they flatly deny there is an issue. Even with data log information indicating the issue and video recording, the nissan tech and general manager are on my side but their hands are tied as nissan australia will not come to the party.
Id love to have the root cause fixed but Nissan so called warranty is useless.
e.g. look at the faulty bonnet catch fix they had for the Nav or even worse still the so called fixes they had for the 3.0l patrol motor that was an issue :S
I've got one of the D40s with a "fixed" bonnet catch. It resembles a poor taste joke, maybe like something by a white American in the 60s.
It's worth pursuing. If it dies completely when you need the thing most you won't be happy about it.
It's worth pursuing. If it dies completely when you need the thing most you won't be happy about it.
K
krunchi
Guest
Lol at the bonnet 'fix'
I know what your saying, i just did a highway test 30 mins ago and could not replicate the flutter/surge or jerk at all, not even a hint where previously it was hard not to experience it!
Id say the turbo is fine, the whoel problem would have been turbulence in the inlet caused by the EGR operation.
Tony how long have you had EGR blocked for now? any down sides besides possible slightly higher EGTs?
I'd say about a month now, and I might leave it in for another month just to get some more towing in with the thing in place so I can see how it performs under constant load.
The down sides: I'm technically breaking the law, the applicable fine is $13,200. I don't know if my EGT is higher - I don't have a means of measuring that.
I notice no smoke at all, at night, in the headlights of the cars behind me. I may have a small amount of extra power right across the range, I definitely THINK there is a little more power below boost range and I'm fairly sure she's boosting a little earlier.
It's all perceptual and may be half wishful thinking - I haven't dyno'd it. But my fuel economy figures seem to have improved - no guarantee that it's not just less lead in the foot, or just the diesel reaching towards 30,000km and loosening up some more.
The down sides: I'm technically breaking the law, the applicable fine is $13,200. I don't know if my EGT is higher - I don't have a means of measuring that.
I notice no smoke at all, at night, in the headlights of the cars behind me. I may have a small amount of extra power right across the range, I definitely THINK there is a little more power below boost range and I'm fairly sure she's boosting a little earlier.
It's all perceptual and may be half wishful thinking - I haven't dyno'd it. But my fuel economy figures seem to have improved - no guarantee that it's not just less lead in the foot, or just the diesel reaching towards 30,000km and loosening up some more.
