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NISSAN PATROL Y61 3.0 Di (ZD30) 09/2000
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The simple answer to your question is that your app makes use of the MAF voltage value to compute grams of air per second, and uses a standard AFR value to turn that into grams of fuel per second.
blocking the EGR increases the MAF voltage value. Hence your App now provides a different eco.
I suspect other apps ask your ECM different data to get the real fuel usage.
in other terms, change app.

Attached is the kind of software which leads to wrong results for eco.
 

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Y2KGUII ZD Wgn
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To me nothing beats filling up and doing a calc, No app required and just a small amount of mental skill will give an accurate number each and every time.
 

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'14 Y61 ZD30 CRD M/T ST
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I can see how that would be better, but my concern is why has the app gone from reporting 16.5L to now 21L (as of today), the only change had been the swirl disconnect & egr block..
I agree. 16.5 to 21 is a massive jump so something else is going on. That’s a 27% increase. Fill up your tank, go for a drive and fill it up again. With such a big difference you won’t have to go much further than 50km to see if your actual consumption is closer to either 16.5 or 21.
 

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'14 Y61 ZD30 CRD M/T ST
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The simple answer to your question is that your app makes use of the MAF voltage value to compute grams of air per second, and uses a standard AFR value to turn that into grams of fuel per second.
blocking the EGR increases the MAF voltage value. Hence your App now provides a different eco.
I suspect other apps ask your ECM different data to get the real fuel usage.
in other terms, change app.

Attached is the kind of software which leads to wrong results for eco.
Very true! Years ago I owned a MkII VW Jetta with Bosch K-Jetronic fuel injection that had a fuel consumption gauge in the instrument cluster. It used inlet manifold vacuum to calculate fuel consumption. I swapped the head for one off a MkIV Golf GTI with a turbo. You can imagine what the fuel consumption gauge did when vacuum all of a sudden turned into 0.7bar boost. :ROFLMAO:
 

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Discussion Starter · #225 · (Edited)
The simple answer to your question is that your app makes use of the MAF voltage value to compute grams of air per second, and uses a standard AFR value to turn that into grams of fuel per second.
blocking the EGR increases the MAF voltage value. Hence your App now provides a different eco.
I suspect other apps ask your ECM different data to get the real fuel usage.
in other terms, change app.

Attached is the kind of software which leads to wrong results for eco.
Okay that's a really good answer hahaha that makes alot more sense.
I agree. 16.5 to 21 is a massive jump so something else is going on. That’s a 27% increase. Fill up your tank, go for a drive and fill it up again. With such a big difference you won’t have to go much further than 50km to see if your actual consumption is closer to either 16.5 or 21.
Agreed. I have driven 90kms since filling up & will have to drive another 150ish tomorrow, after that i'll fill up & post back here. So far the fuel gauge itself is moving a little bit faster down to E so I worry..

Could blocking egr with an exhaust manifold leak cause any issues? boost was alot higher crusing at 100 yesterday too, almost maxing out at 16.5 psi when it would usually hover between 12 & 14 psi (courtesy of geeyou's tillix instructions).

Also, is it possible because I have no gaskets between the EGR pipe that it is improperly sealed? should I buy 1 or 2 gaskets to put either side of the shim?
 

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Discussion Starter · #227 ·
Maybe your neighbor put potatoes in the muffler?))

View attachment 548078
Thats a doozy.
I agree. 16.5 to 21 is a massive jump so something else is going on. That’s a 27% increase. Fill up your tank, go for a drive and fill it up again. With such a big difference you won’t have to go much further than 50km to see if your actual consumption is closer to either 16.5 or 21.
Did the test, came out at 16.3L per 100km so no worries there now, simply an misreading in the app like Phdv61 stated. Though I am still unsure of the EGR block, the car definitely has more torque, but drives different and has a little less to give in higher rpm? does that get corrected with a 3" exhaust?
 

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Thats a doozy.

Did the test, came out at 16.3L per 100km so no worries there now, simply an misreading in the app like Phdv61 stated. Though I am still unsure of the EGR block, the car definitely has more torque, but drives different and has a little less to give in higher rpm? does that get corrected with a 3" exhaust?
ZDs, like most big 4-cyl diesels, don’t like revving. Most of us aim to have more torque at lower rpms, because that is where you actually drive the thing.

Saying that, without reading through 12 pages and 227 posts again, you started off by saying your Patrol is stock, apart from a 2” lift and 33s. I take it you now also have the EGR blocked and the swirl valves disconnected, but nothing else. If that’s the case then you are pretty much where I was with mine, prior to installing the MagicBox, but I still have my swirl valves connected. (Still waiting for someone to provide facts backed up by evidence that it actually makes a difference.)

I havenoticed any difference in performance with and without the EGR blocked. The only difference I do notice is a slightly different engine “tone” at low throttle and low rpm (which is where the EGR operates most of the time). At 16, your fuel eco is a bit high, but not entirely off the chart. (Mine is between 11 and 12 atm.)

A 3” exhaust (or the more commonly recommended 2.75” for a CRD) won’t make much difference without a tune, or if you’re willing to put in the effort, at least some other form of boost control e.g. needle valves or MB.

I don’t trust seat of the pants dynos. You’d have to convince me with a dyno chart that you have more torque after blocking the EGR.
 

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Discussion Starter · #229 ·
ZDs, like most big 4-cyl diesels, don’t like revving. Most of us aim to have more torque at lower rpms, because that is where you actually drive the thing.

Saying that, without reading through 12 pages and 227 posts again, you started off by saying your Patrol is stock, apart from a 2” lift and 33s. I take it you now also have the EGR blocked and the swirl valves disconnected, but nothing else. If that’s the case then you are pretty much where I was with mine, prior to installing the MagicBox, but I still have my swirl valves connected. (Still waiting for someone to provide facts backed up by evidence that it actually makes a difference.)

I havenoticed any difference in performance with and without the EGR blocked. The only difference I do notice is a slightly different engine “tone” at low throttle and low rpm (which is where the EGR operates most of the time). At 16, your fuel eco is a bit high, but not entirely off the chart. (Mine is between 11 and 12 atm.)

A 3” exhaust (or the more commonly recommended 2.75” for a CRD) won’t make much difference without a tune, or if you’re willing to put in the effort, at least some other form of boost control e.g. needle valves or MB.

I don’t trust seat of the pants dynos. You’d have to convince me with a dyno chart that you have more torque after blocking the EGR.
Yep, thats right she is stock with no tune. I definitely have noticed a difference in the way it sounds & drives with EGR blocked, which worries me but people far more educated than myself regarding patrols have had positive results in doing so. Yeah im OK with 16 though as it was higher but I fixed the car bit by bit and it came down, so hopefully with a few more repairs i'll be close to you!

I do already have a tillix installed, and i've read new 3" exhaust can make up to 10% difference in power if the right conditions are met, not sure how true that is though.

If I had the money I would! I'm very good when it comes to feeling a difference when making changes to the car which is why every little thing keeps me up at night hahaha. If I could id let you test drive mine with & without EGR blocked, you would definitely see what I mean.. (its not a HUGE difference either, just more torque early on and less later in rpms)
 

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Y2KGUII ZD Wgn
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ZDs, like most big 4-cyl diesels, don’t like revving. Most of us aim to have more torque at lower rpms, because that is where you actually drive the thing.

Saying that, without reading through 12 pages and 227 posts again, you started off by saying your Patrol is stock, apart from a 2” lift and 33s. I take it you now also have the EGR blocked and the swirl valves disconnected, but nothing else. If that’s the case then you are pretty much where I was with mine, prior to installing the MagicBox, but I still have my swirl valves connected. (Still waiting for someone to provide facts backed up by evidence that it actually makes a difference.)

I havenoticed any difference in performance with and without the EGR blocked. The only difference I do notice is a slightly different engine “tone” at low throttle and low rpm (which is where the EGR operates most of the time). At 16, your fuel eco is a bit high, but not entirely off the chart. (Mine is between 11 and 12 atm.)

A 3” exhaust (or the more commonly recommended 2.75” for a CRD) won’t make much difference without a tune, or if you’re willing to put in the effort, at least some other form of boost control e.g. needle valves or MB.

I don’t trust seat of the pants dynos. You’d have to convince me with a dyno chart that you have more torque after blocking the EGR.
I do understand where your coming from. I've lost count of the number of dyno's I've had over the years, many years ago I knew a guy with a dyno, I had an agreement with him that after I did a mod I got a power run at bargain basement price so that I knew what I had done added to performance, I cannot remember a backward step yet, I did get a surprise when the CCIC I fitted only produced 4hp, but the torque went up and came in lower, so it was a win.

Secondly the good thing about an ECUTalk is engine info is right there in front of you, so if you see MAFv go up for a setpoint after a mod you know it is working better.

Dyno's can be misleading, but if you have the same operator on the same dyno then that is a good start, but, a dyno does not measure driveability, ie, my old girl also spent a lot of time on another dyno with the same operator while a turbo was being developed, on the dyno we had it running at 28psi then 30psi then back to 25psi (now 24psi), sure the dyno charts showed improvement as boost went up, test drives were also done on road at 30psi then at a lower 25psi, you would be hard pressed to pick a damned difference, but I'm not driving around anywhere with 30psi and as said it now sits at 24psi and it feels great.

I have two dynos I use in my quest for improved driveability, my seat of the pants dyno which does work well and a stop watch dyno to time 60-80k then 80-100k then an overall 60-100k in 4th gear on the same stretch of flat road, that one tells a story completely.
 

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a stop watch dyno to time 60-80k then 80-100k then an overall 60-100k in 4th gear on the same stretch of flat road, that one tells a story completely.
I was going to say, this is probably the best way to check for small changes if you don’t have access to a reputable dyno and operator.

Just for reference, here’s an extract from the ESM on the Swirl valve function.
Font Rectangle Parallel Number Pattern
 

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NISSAN PATROL Y61 3.0 Di (ZD30) 09/2000
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@AndrieK, you will notice that the swirl is open when … the EGR is not supposed to be operating (cold temp, very high temp, high RPM / load demand).

if your EGR is blocked, it can be left open all the time.

Last point, if your EGR is blocked, and the swirl valve does not work as it should, idle is rough.

These are the reasons why I believe the swirl valve is needed only if your EGR is not blocked or disactivated. Otherwise, it tends to reduce a bit the flow of air (MAF voltage) and the turbulences needed to better mix the exhaust gaz and fresh air are no longer required.
 

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Y2KGUII ZD Wgn
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I spent a lot of time gathering data on the swirl valve function through the ECU before disabling it, I know the CRD is a little more efficient but that is to be expected.
I also know the EGR block and swirl valve disconnect plus my later removal of shafts and bearing housing 'lumps' in the throttle body all made a small contribution.
We often here about 1percenters, I embrace those as if I do 10 of them I've made a 10% improvement.
 

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I have two dynos I use in my quest for improved driveability, my seat of the pants dyno which does work well and a stop watch dyno to time 60-80k then 80-100k then an overall 60-100k in 4th gear on the same stretch of flat road, that one tells a story completely.
What are your current times for these runs?
I don't think I've seen a thread on this.
Sounds like a great way to compare the many different engines and mods we are all running.
 

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Y2KGUII ZD Wgn
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From what I read in the translation this device measures speed and time achieved from zero, if I'm reading it correctly. This doesn't interest me in the slightest, what I'm after with my test is driveability, hence the testing in 4th gear, 60-80, 80-100 and then an overall 60-100 on the same bit of road. My ECU talk can tell me 0-60, 0-100 and standing 400m, but the test I do reveals more about torque than it does about Hp and that is what I'm interested in.
 

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Discussion Starter · #238 ·
Howdy fellas, did some more testing over the weekend/yesterday. drove 250kms (200kms on freeway) and got a result of 16.2L per 100km. Now that figure was in line with my out and about in town eco but definitely not my freeway kms prior to EGR block. I double checked my work & can only assume the EGR block was the cause so will be taking it out. Unfortunately the mod does not sit well with my car & it already has rubbish fuel eco so will keep chasing my tail to figure this out.

Cheers
 

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2013 GU Patrol Wagon ZD30 Auto
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Howdy fellas, did some more testing over the weekend/yesterday. drove 250kms (200kms on freeway) and got a result of 16.2L per 100km. Now that figure was in line with my out and about in town eco but definitely not my freeway kms prior to EGR block. I double checked my work & can only assume the EGR block was the cause so will be taking it out. Unfortunately the mod does not sit well with my car & it already has rubbish fuel eco so will keep chasing my tail to figure this out.

Cheers
regardless of EGR, when calculating fuel consumption, don’t forget to adjust for your bigger than standard tyre size. My real distance is more (and fuel consumption is less) than what odo shows by exactly 7% with 33s.
 

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Discussion Starter · #240 ·
regardless of EGR, when calculating fuel consumption, don’t forget to adjust for your bigger than standard tyre size. My real distance is more (and fuel consumption is less) than what odo shows by exactly 7% with 33s.
I was lucky enough to have it bang on with 33" boots on the car. Did testing with gps on maps and it came out exact every time, not sure if thats the correct way to gauge how out the odo reads or not?
 
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