Help with my evoscan data logs.

[Davezj]

yes a boost gauge is useful, just connect it to the smaller of the two vacuum/boost pipes that are coming of the back of the plenum chamber by the throttle body. the larger one is vacuum assist for the brake servro the pipe for that has a one way valve inside the pipe don't bin this pipe and replace it, unless you replce the one way valve in the new pipe. the smaller pipe goes to the front of the car and down to the recirc vent valve for the turbo. put the T piece in this pipe and run it to the gauge. don't use the pipe coming off the front of the throttle body as this goes to the fuel pressure regulator solenoid and you don't want to disrupt this vac/pressure.

just thought i would pass this on to you

[nos monkeys]

Thanks for that. when it stops raining ill take the boost gauge from my legnum and put in my 300 to double check its the gauge broken, im only going by what the mitis mechanic told me so not 100% sure its the gauge, but i did do a boost leak myself and it was good.

Will go out now warm my car up and take as many videos as i can befor ei run out of memory and get some better data logs ending as it runs rough.

[Davezj]

look forward to seeing the videos and logs, and it make perfect sense to test the boost gauge, before forking out for a new one.

when doing a boost leak test there are lots of areas of the boost pipe system which can get missed out and not checked when they are done. did you spray all the pipework with soapy water to show up the leaks or did you just listen for leaks. you can still have some major leaks and not know about it if you don't spray all the connections with soapy water.

[nos monkeys]

i didnt actually spray it with soapy water but it held 5psi without dropping and i couldnt hear any noises. where as the same day i done a boost leak on my 300zx it lost all pressure pretty quick and that had a few leaks and some small ones and the vr4 defiantly was better than my 300, and my 300 still holds 9psi boost and drives without problems and since this problem is so tempermental i dont think it would be a boost leak unless its only leaking on occasion somehow.

some reason my logs i done before were all weird but have just been out and redone them with some videos havent looked at them yet but will edit this and post them on here, out of the runs i done twice it ran fine, not sure which logs they were though i forgot but it would be in the first half, but otherwise it didnt really run 100% though out all the logs and videos.

1.zip
2.zip
3.zip
4.zip
5.zip

[nos monkeys]

6.zip

here is a link to the video, will update this soon with particular times to look as sometimes it runs ok then it doesnt so you can hear the difference in engine noise.

https://www.youtube.com/watch?v=8m_4...ature=youtu.be

start of video first pull it ran okish then skip to 1:05 and listen to the difference also again at 1:40 at 2:00 from 4k till 5k it done it but the power came back at 5k just as i changed gear, you might be able to hear the tone of the engine go from good bad good. 2:15 it kept going on off on off on off but hard to tell on video. i think the last pull was also when it was running semi normal but its really hard to tell what is normal now . . . .

it acts up sound different and this is my problem, this is only a minor bit it does get worse but its very tempermental and i havent managed to get it doing it bad on camera or log.

if the logs are ok and you have no idea by the video, would coils/plugs/leads breaking down show on the log in any way? i was thinking of replacing the rear 3 plugs but thats really all i can afford $60 for 3 plugs is like a week and a half of my spending money lol and at least then i can change the front ones later one. but not sure if i should try get some leads to replace while im at it although no idea how expensive they are. i dont really have any idea what it is


iv just been and checked that boost gauge on my 300 and its reading what it should, well my gf said it was about 8-9psi and its running 9.5 so its close enough and showing over 5psi which is the max in the legnum. now why did the mitsi dealership tell me there is no boost leaks its running 7psi and my gauge is broken, and how and where did they even pull the 7psi figure. . .my boost gauge is hooked up to behind the plenum where it is meant to be there are no kinks in the vacuum line or splits. even when i pulled the wastegate lines off so it was free boosting it still never read over 5 psi. . . not sure what is going on with this car. . . i defiantly brought that guys problems and i really want to go rip his face off. i have 2 months before the baby is due the amount of money i have spent on this to get it all ready now iv got no move savings and still not a reliable trust worthy car which i dont like driving incase it blows. so far this has costed me 8,000 nzd and still nothing special.

[Davezj]

sorry, it is a bit pointless listening to the videw as that rattling masks the sound of the engine.
can you stop what ever is rattling for rattling and do the video again.
are you videoing it with a video camera or a phone, it sounds like and old video camera as these often had problems with internal noise due to the mechanical image stablisation methed they used. if you shook the camera too much you would get parts hitting eachother inside the camera and this noise would be added to the recording. my camera does the same thing on track days.
sorry but i can't hear anything different, all i can hear is the rattling.

as for your boost gauge, i think the issue is the way it has been connected to the vac/boost line on the plenum, i have see some boost gauges come with a T piece that has a wide freee flow of air throum the straight part of the T piece and then a very small pipe coming off this which goes to the gauge. the pipe is just not big enough and restict the pressure getting to the gauge. check yous and replace it for and equal size T piece on all entry/exits.
i have seen also just bad installs where the worng size pipe has been used and tape has been wrapped round the T piece to build up the diameter of the T piece to make the oversized pipe fit on to it, but the tape has been applied very badly and partially blocked the opening in the T piece.

buy the way the smaller exit on the T piece was used to try and smooth out the response of the gauge so it does not bounce around and overshoot the correct reading. which is understandable but the exit is just to small.

fixing other people mistakes (by this i mean the previous owner) is never a nice thing to do, you just have to make yourself think like the person that made the mistake originally and try and make as many bad decisions as you can to try and get into the mind set of the person that made the mistake in the first place, to see if you can find the issue.

[nos monkeys]

the boost gauge isnt t-d in anywhere it has its own vacuum line ill grab a photo of the vacuum port its on tomorrow, it was probably the camera hitting on the plastic on my dash ill try get better videos.

[Davezj]

i have been having a look at you logs and i have realised the 1 byte load does not seem to work on at all in evo scan but you do have the ECUload logged and this reaches about 140 load so if this value is correct then you should be boosting to about 0.7-0.8 bar i is a little tricky to say for sure as i don't use the ecu load figure i use the load 2 byte mod and i don't know if these two figure match up.

i can't see any obvious issues with the logs to be perfectly honest wth you.
however first gear logs are not the best to do, it is much better t do a third gear log jst from the point of view everything happens so much slower and more data points can be recorded as things change.
in your logs, you only have about 4 data point over the 4K-5K rev range where you say the issue is, this is not enough data the rpm point are about 3900, 4250, 4500, and 5000, it is like watching a film and only seeing one fromae of the movie every second, you don't get the full picture.

[TAR]

I would put my money on the spring in the dump valve being weak. I think the dump valve may be letting by air at high boost.
Do you have another dump valve you could try?

[Davezj]

tim have you got your cable yet?
the offer of the mmcflash dongle still stands when ever you want it.

[nos monkeys]

i have been having a look at you logs and i have realised the 1 byte load does not seem to work on at all in evo scan but you do have the ECUload logged and this reaches about 140 load so if this value is correct then you should be boosting to about 0.7-0.8 bar i is a little tricky to say for sure as i don't use the ecu load figure i use the load 2 byte mod and i don't know if these two figure match up.

i can't see any obvious issues with the logs to be perfectly honest wth you.
however first gear logs are not the best to do, it is much better t do a third gear log jst from the point of view everything happens so much slower and more data points can be recorded as things change.
in your logs, you only have about 4 data point over the 4K-5K rev range where you say the issue is, this is not enough data the rpm point are about 3900, 4250, 4500, and 5000, it is like watching a film and only seeing one fromae of the movie every second, you don't get the full picture.

I'll grab some 3rd gear pull logs later this week although i dont think iv ever had a problem in any of those gears its just 1st and sometimes 2nd but i could be wrong.

[nos monkeys]

I would put my money on the spring in the dump valve being weak. I think the dump valve may be letting by air at high boost.
Do you have another dump valve you could try?

you mean blow off valve? i only have my stock ones on my 300zx, the one on my vr4 is a blitz one and this could be the problem but don't have money to switch it over and check, although this valve is adjustable i might try tighten it. the only problem i noticed with my blow off valve is im not sure if its normal since iv never had one before but if i rev the car and it goes pshhh the blow off valve doesnt close fully after untill i hit the gas again, its done this since forever i did pull it apart and lube it up but still done it, it shuts fully as soon as i touch the gas pedal though not sure if this is normal.

here are pictures of where my boost gauge is connected to, and also where my blow off valve is connected to. please let me know if i should reroute any.

oj9q.jpg this is my blow off valve
o5qp.jpg this is where the vacuum line for it goes to.
9jyj.jpg this is my boost gauge line

[Davezj]

odd that it should only do it in the lower gears.

do you have an origional recirc turbo valve, it really should have a recirc type on there. it is well work checking, or even just swap the one you have on you other car to do a test, it could well be an issue with the spring rate as it is an after market BOV.

[nos monkeys]

yeah thats what i thought, but then again since its noticable in the lower gears im not actually sure its running 100% in the higher gears it might just be less noticeable, but i can get off the clock from 3rd-4th -5th without any noticeable problems yet if i pull over and try from first all hell breaks loose.

Also it seems to do it more if im cruising for awhile and then decide to give it gas in first, like if iv just done 10kms sitting at 100km cruising nicely then pull up and try take off in first thats when it seems to be worse, but if im going around corners putting my foot down heaps in 3rd and just having some fun it doesnt do it as bad when i take off in first. which is why i thought maybe a stuck regulator where it gets use to sitting at cruising speed then cant adjust fast enough when it hits boost. and because it had been disconnected for 8months because the previous owners had no idea about nothing.

il go out now and tightening the spring in my blow off valve and see if it makes a difference i might try find a recirc valve also, mine has one on there but the vacuum line port on it is snapped off flush so wouldnt be able to use it. they never took it out and blocked it off, although i dont think it leaked during the boost leak test

[Davezj]

deleted post

[Davezj]

you mean blow off valve? i only have my stock ones on my 300zx, the one on my vr4 is a blitz one and this could be the problem but don't have money to switch it over and check, although this valve is adjustable i might try tighten it. the only problem i noticed with my blow off valve is im not sure if its normal since iv never had one before but if i rev the car and it goes pshhh the blow off valve doesnt close fully after untill i hit the gas again, its done this since forever i did pull it apart and lube it up but still done it, it shuts fully as soon as i touch the gas pedal though not sure if this is normal.

here are pictures of where my boost gauge is connected to, and also where my blow off valve is connected to. please let me know if i should reroute any.

oj9q.jpg this is my blow off valve
o5qp.jpg this is where the vacuum line for it goes to.
9jyj.jpg this is my boost gauge line

your bov is connected to the wrong place, it needs to be connected to the plenum chanber where your boost gauge is connected to.
when you lift off the throttle the bov vac line is not seeing a propper vacuum as it is connected to the turbo side of the throttle body. when the throttle body closes it is supposed to create imediate vacuum to the BOV and release the pressure in the turbo pipes. but when you lift off the accelerator and the throttle body closes the bov is still seeing the pressure in the turbo pipes. you need to get this plumbed in correctly before doing anything else.
this is why it is not working propperly, nothing to do with a faulty valve.

[Davezj]

il go out now and tightening the spring in my blow off valve and see if it makes a difference i might try find a recirc valve also, mine has one on there but the vacuum line port on it is snapped off flush so wouldnt be able to use it. they never took it out and blocked it off, although i dont think it leaked during the boost leak test

i am not sure what you mean be this statement.
please tell me you don't mean you have two valves fitted one BOV and one broken Recir original with no vac line going to it.

[fassi1]

Regarding fuel trims.
I would recommend to get some basic knowladge which will massively help to understand and read any kind of logs.
"Open loop, closed loop, cut off, long term fuel trim, short term fuel trim" are definitely the ones must know.
Our ECUs switch from closed loop to open loop very often and that's when fuel trims start changing.
Parameters like duty cycle or injector pulse width and oxygen sensor sygnal (voltage) are very handy too when logging.

[nos monkeys]

i am not sure what you mean be this statement.
please tell me you don't mean you have two valves fitted one BOV and one broken Recir original with no vac line going to it.

the top of the bov has a bolt and allen key bit which adjusts the spring inside so it either becomes easier to open or harder, and i thought that's where its meant to go yesterday i actually put the bov line on where the boost gauge is as well and t-d it there but it didnt work at all i think the vacuum line i had was to small though, ill get some bigger vacuum line and redo it there and while im at it ill replace the vacuum line going to my boost gauge for some bigger stuff and see if that fixes it. what size vacuum line should i be using for the boost gauge and bov? i think the stuff which is connected to it is 4mm

and yes thats what im saying lol it has the blitz bov fitted how it is now and then it still has the stock recirc valve that has a broken vacuum line but its still plumbed in. it is on my list to find some blanking plugs to take the stock recirc valve out. and just to remind you this was all fitted before i brought the car lol you should of seen how the boost controller was connected this car was a mess and i didnt even know how bad since it was my first turbo so fitting all this stuff is new. i did the best to bring it back to how it is stock, will get the bov fixed this week and try find some blanking plugs and remove the stock valve

[TAR]

The 2 dump valves will definitely be causing an issue. You must get rid of the old recirc one and blank off the pipes. No amount of evoscn logs will help fix a car which is not plumbed up right!