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3uz throttle map


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Hi there

I have some throttle map issues i would like looking an by an expert to see if they look correct. My car got mapped around 3 months ago, its a 3uzfe 4.3L Lexus V8 on Link G4+ extreme using factory lexus e-throttle controlled by the Link. I've never been entirely happy with happy the throttle was mapped as for example, if i wanted to go wide open throttle, i never felt like the pedal needed to go past 75% as it already felt like wide open throttle, but i persevered and learned to use it that way. 3 days ago i had my first drift day, and i kept getting throttle faults and my e throttle relay would shut down all together, unfortunately being stranded in the middle of the track i didn't save / memorise the codes, and didn't take a data log either!

I took my car back to my tuner yesterday and asked him to have a look through my throttle map as i presumed something was wrong, he made a few changes and made it 100times worse, so i've sort of lost my faith with his throttle mapping capabilities.. So, long story short, i took the car away, got my laptop out, went down a long country lane and played with my PIDS and throttle map tables until i felt like i had the pedal i should have, and so far no faults either which is good

The first map i've attached is my tuners throttle map (MGT map, agg throttle) , the second is my own throttle map (MGT map, self tuned throttle target good)  Can someone look at the 10% AP and 20%AP range and tell me if what hes done is stupid or am i not reading it correctly.. It progressively opens the actually throttle body as RPM increases, but not as AP position increases... basically meaning the car would accelerate without actually adding any more throttle pedal position?! that seems daft.. so the second map is my own attempt at a throttle target table and the pedal feels how you would expect when driving a car


Many thanks for looking, any feedback would be great!


MGT map, agg throttle.pclr

MGT map, self tuned throttle target good.pclr

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For Throttle target there is not really any right or wrong - it purely comes down to driver preference.  Some like lethargic movement for the first 50%, others prefer the more snappy feel as soon as they touch the pedal.  


On 5/19/2018 at 9:33 PM, BulletFactory said:

Can someone look at the 10% AP and 20%AP range and tell me if what hes done is stupid or am i not reading it correctly.. It progressively opens the actually throttle body as RPM increases, but not as AP position increases... basically meaning the car would accelerate without actually adding any more throttle pedal position?! that seems daft..

Yeah I agree, that is a bit of a weird setup and it could cause a fairly odd driving feel. 


However the target table is unlikely to have caused any errors.  The PID's in your self tuned map are no different than the original map.  TP calibration looks a bit odd too as both Sub and main voltages are identical, unless both inputs are wired to the same sensor, that is too much of a coincidence to be correct.  Can you do a PC log of a short drive, that should give us some clues to what is causing your error.

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There are a few weird things in this map, and not all of them relate to throttle control. 

Firstly, as Adam pointed out your APS and TPS are both configured to what looks like the same sensor. The upper and lower limits for both main and sub values are the same, and the last running info that ECU saw before you saved the log showed that both the main and sub values were identical (for both APS and TPS). This isnt going to instantly break anything but it means you have no way of catching a failed APS or TPS, or a way to filter out odd inputs from electrical noise as you have nothing to compare to. You should really be running main and sub to separate ECU inputs. You could re-run the APS and TPS calibrations as a starting point and check you get the same high and low values. This is a likely candidate for you throttle faults.


Regarding the values in the ethrottle target table, both tables should perform well enough but I guess its personal preference. What could be making it a bit odd is that your ethrottle idle control is set to kick in at anything under 5% throttle/1300rpm (give or take, temperature dependent). This may make it feel like you need to give it quite a bit of gas to get it to respond, especially when combined with the slow ramp up of throttle target postition. You could try dropping the AP% lockout to 2% or so and see if you like the feel of it. If it wants to stall when returning to idle after this then bump it up a bit. Your ignition idle control is also set to the same 5%AP and 1500rpm, and the ignition values from your main table at idle vs those in your ignition idle table are a long way apart (28ish main table vs 15 idle table), again this means there will be a lot less power just off idle and the suddenly have it come on when it drops out of idle control at 5% throttle. There is also a bug floating around in the current ECU code around idle control when you dont have a speed source selected (which you dont).

You've also got VVT targets that are TPS based and are 0 below 10% TPS, then jump to 30 deg. Sharp transitions like this can be noticeable depending on the engine, and while having this TPS referenced instead of MAP will still work, its going to make the engine be constantly changing its target vvt angle which isnt instant so you may be "off target" quite a lot of the time.


Your main fuel table is referenced to AP% and I'm not sure why. TP% is a reasonable config on some engines, but relatively rare on on cars with a normal throttle plenum. AP% as a fuel reference is asking for trouble given that your AP vs TP table isnt 1:1. It also means that normally harmless changes like you've been making to the AP vs TP target table actually affect your fuel numbers! If you change this to TPS it will still be roughly correct (and will be closer to correct at high load), but it will throw your whole tune off a bit. If you dont "fix" this though, I'm not sure you will be able to make much in the way of ethrottle changes though without screwing your tune anyway.

You also have some strange engine protection config. Fuel pressure appears to be configured but is reporting 0kpa in the last runtime values window, and its not referenced in any safety RPM limits etc (maybe its not acutally connected?). Oil pressure is configured on an input and is used as part of the GP RPM limit to protect against oil pressure loss (good), but both sensors have the  "error condition" value set to ~1000kpa though - ie if the sensor goes out of range (disconncted, fails, etc), the ecu behaves like its got really high fuel/oil pressure so it wont limit RPM from this.

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Wow that's alot of information to take in and try and get my head around! I took my car for tuning and i've left everything as is until i had this throttle fault which i tried to rectify myself, i had to else i'd lose the whole day!

My throttle Main and Sub are connected to one track as i was having issues trying to run my throttle calibration, i bridged them together and it worked fine, and was told that it should be fine like this? Trying to source another throttle body for this engine in the UK isn't easy and it's super expensive, so tried to make do.

Regarding VVTI targets, i will have to talk to my tuner, who i seem to have lost some faith with after reading your comment. My problem is, is that i have a drift day on Monday and my tuner is now on holiday for 2 weeks..

For failsafes, i planned to wire in fuel pressure but the fittings i got sent were wrong and i ran out of time before tuning so had to do without it. Oil pressure is actually wired in and reads, and i asked for the oil pressure to be set as a failsafe, but clearly he has not done this correctly. 

I have attached 2 driving data logs, i tried to squeeze in as much different throttle, gear, driving conditions as i could, and i'm still not getting any throttle faults and it does feel better, one thing i have noticed is that i'm running ever so slightly richer now, hovering around the low 14's, almost into 13AFR on cruising throttle, which backs up what you said about my throttle and fuel tables, and obviously me playing with the throttle table has now effected my fueling and effectively my whole map!

I really appreciate the feedback and help on this guys, i've been waiting to drift this car for years and now my first big drift day is coming up i'm not feeling so confident!



driving log.llg

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Just had a thought about the TPS vs APS fuel map. If you feel like playing with excel for a bit, you should be able to take the fuel map you have, and the original APS>target table, and with some calculations work out what the equivalent TPS should be for every cell, and use this to generate a new Fuel map that is TPS based. This will be a lot of excel tweaking but means you can keep your tune and move to TPS based fuel map.

Regarding the oil pressure safety - there is a GP RPM limit table set using oil pressure so as long as the sensor is working, your tuner has set up a safety for low oil pressure. The bit that isnt right is that if the sensor itself fails, it will fail to a high oil pressure number rather than low. This is simple enough to fix by changing the error condition in the oil pressure input to 0kpa. (same for fuel).

You have both TPS and APS set to single track. If you just have a flaky TPS, you can still run APS with both main+sub sensors so you still get some level of protection against noise/sensor issues.

I guess the good bit here is that most of the issues i've pointed out are around near idle performance rather than full throttle, so you should actually be ok to drift it. (once you fix the oil pressure failure condition).


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I don't feel confident enough with being able to change the map like that as tuning isn't my strong point, i've literally tried to learn what i can in the space of a couple of weeks to try understand whats going wrong. I understand about changing the fuel map to TPS instead of APS, but don't feel confident enough doing it myself, although i might sit down one night this week and try get my head around it and see if i can work it out. I've saved all my previous maps including the one from the tuner so i can always resort back anyway. 

Regarding VVTI table, would you say it's "safe" as it is, with it jumping to 30degrees at 20% APS? 

All i'm hoping for is that the map is currently safe and usable for my drift day, as i've been waiting a long time to do this day, and i guess a bonus is that i'm still naturally aspirated so running a tad richer shouldn't have too much of an impact. I will change my oil pressure failsafe so it works, and after my drift day i'm re-doing my fuel system anyway so will have fuel pressure monitored too.

When you say about APS with both sub and main, that is what i'm current running, the sub and main is wired into separate inputs, it's only my TPS that is wired into one input as one of my sensors in my throttle is faulty and until a decent second hand throttle body comes up for sale there isn't much i can do about it as Toyota will want around £600 for a new throttle body!

Thanks for your help and support!


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Are you sure the APS wiring is being fed from 2 different outputs on the throttle pedal? both AN6 and AN7 (APS main and sub) track EXACTLY the same voltage for your entire log. It would be odd for a pedal to output the same voltage on main and sub sensors, and also odd for them to track 100% perfectly. You'd normally expect fractions of a volt differences between the sensors. Its not immediately urgent though as the numbers from it look normal enough (it goes from 0 to 100 and doesnt look to jump around randomly). Just a slight risk running it this way if the sensor fails to 100%.

As a drift car that spends most of its time at high rpm, the good news is that whatever is in your fuel table, it ends up around 0.84 lambda at full throttle which is pretty much right where you want it on an n/a. maybe a little lower if its getting too hot at the end of a run but its a perfectly safe number to start with. Your throttle feel issues mostly seem to be at lower rpm so if its a pure track car you could just ignore them and be safe, even if its not optimal. It goes really rich on throttle tip in - 0.65 ish - but it doesnt stay there so unless you get stutter on acceleration this probably isnt worth trying to fix if you're not comfortable doing it.

the VVT table is safe (typically OEM's put mechnical stops in the VVT mechanisms so you cant cause piston>valve interference even if the cams go uncontrolled), it just might feel jumpy around that point. Its low in the rev range though and for a drift car shouldnt really be noticed as I doubt you spend much time at 2000rpm. What is a little more concerning is what looks like PID overshoot causing VVT target oscilations in your log (the wavy line at the bottom between 0:58 and 1:00). the target here is 35 for that whole range but you can see it repeatedly goes over/under target and corrects itself. You can then see one bank (green line) settles quicker than the other, but neither should do this at all. On a factory valve train and pistons you arent likely to have interference from this but its not ideal for power and TBH ive never run a car doing this for long enough to know if it puts added strain on anything, gut feel is its not something you want to leave though. 

I'm not sure if the 3uz and 1uz VVT solenoids are the same but i'd guess they are slightly different and the default PID settings arent sufficient to control VVT accurately. There are ways to tweak these settings a bit using custom PID values but tuning these is risky and best bet would be see if the link guys can advise if any of their internal docs mention what VVT PID settings work on a 3uz. Maybe you can just select the VVT control algorithm for a similar engine if the link guys can figure out which pre-deifined setting will be best.


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12 minutes ago, cj said:

I'm not sure if the 3uz and 1uz VVT solenoids are the same but i'd guess they are slightly different and the default PID settings arent sufficient to control VVT accurately. There are ways to tweak these settings a bit using custom PID values but tuning these is risky and best bet would be see if the link guys can advise if any of their internal docs mention what VVT PID settings work on a 3uz. Maybe you can just select the VVT control algorithm for a similar engine if the link guys can figure out which pre-deifined setting will be best.

The 1U default PID's usually work fine on the 3U assuming oil press and viscosity is close to factory specs.  The problem in this case I think is he has 70psi oil pressure at 1900RPM in that region of wonky cam control you show above.  By 5000RPM it is showing 110psi if we can believe the oil press sensor...  I would be worried about racing this car if this is true, the oil filter wont be far off exploding.

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Hi Adam,

I'm running factory oil viscosity, and i have 2 oil pressure sensors, one for the link and one for a gauge, and on full throttle i usually show around 7bar / 100psi of pressure when hot on my gauge. I know early 1uz factory oil pressure should be around 85psi when hot, so figured that 100-110psi might be standard for the later 3uz, but cannot find factory pressure specifications to confirm this. So you think my VVT oscillation is being caused by excessive oil pressure? I've put around 500 road miles and gave the engine some good abuse at my last drift day and everything seemed okay other than my throttle fault.

I will double check my APS wiring tonight. I think after my drift day monday i'm going to have to have a serious re-think about a few things, one being my tuner, and two investing more into better sensors and more of them, including speed, fuel and oil pressure



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28 minutes ago, BulletFactory said:

I know early 1uz factory oil pressure should be around 85psi when hot, so figured that 100-110psi might be standard for the later 3uz, but cannot find factory pressure specifications to confirm this

You could be right, it seems higher than I expect at hot but they may run an especially high oil pressure for some reason (or there could be something wrong with the relief valve).  In a previous life I used to build dry sump systems and the common ford oil filter that we had on the test bench would blow up like a balloon at about 130psi, so that is where my worry came from.  If you have 110psi when hot I would expect it is quite a bit higher when cold.


37 minutes ago, BulletFactory said:

So you think my VVT oscillation is being caused by excessive oil pressure?

Yes that was my original thought but I was assuming these things had a more typical OP, like say 50psi.  Now I dont really know.  If your current oil pressure is normal then it looks like you will need to use the custom PID setting to get the cam control better.  



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So i managed to find factory 3uz oil pressure figures: At operating temperature it should be 43-85psi at 3000rpm. So it appears i have a possible oil restriction issue causing high oil pressure. I have remote oil filter housing, and oil cooler using AN12 lines and OEM Toyota oil filter. The engine is standard with factory oil pump etc. And seems as both gauges read the same high oil pressure, i would be fairly certain that i do actually have high oil pressure for whatever reason.

Do you think the vvti oscillation could cause what would feel like a throttle fluctuation? Because when i was drifting at higher load (3rd gear around 3500rpm) it felt like the throttle was juddering, and then if i didn't change my throttle input and kept trying to drift under that condition, the ecu would eventually shut down the e throttle relay, i wish i could have got a data log of this but i can't get it to replicate on the public roads. 




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if normal range is 85psi @3000 then you are right on the edge of it but still just on normal. Couple of places in your log you go through 3000rpm under throttle and oil pressure is mid-high 80's.

Was that stutter+throttle cutout before or after you removed the effectively removed the tps sub connection? Some/most of the methods of failure that will trigger an ethrottle cutout will cause the ecu to log a fault code (which are not lost until manually cleared). I take it you did not see any codes when you connected to it afterwards? What troubleshooting did you do to conclude that the tps sub sensor was faulty - ie is it possible this was misdiagnosed and the same fault is still present and affecting the throttle control now?

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59 minutes ago, BulletFactory said:

Do you think the vvti oscillation could cause what would feel like a throttle fluctuation?

In that screenshot above the cam is bouncing between about 35 & 40deg.  The target was 35deg so you could say 5deg either side of target.  So that would definitely make a measurable difference to torque output but Im not sure how noticeable that would be to "seat of the pants".  I dont see any evidence in your log that the throttle is oscillating so the VVT is a possible explanation.


Looking at your log I think the reason for your original "throttle error" complaint is probably the E-throttle PID is too conservative so the throttle is too slow to react to small errors.  In the example below you can see in the area where my yellow cursor is, the E-throttle 1 target is 2% but the TP main is sitting at 6% and kind of sits at 6% for a while before it finally corrects.  If there is more than a couple of % difference betwwen the Target and TP main, for some short time period (sorry I dont know the time period of the top of my head) then the ECU will will increment the TP/Target error accumulator by 1, if the error persists it will continue to count upwards.  In this log you can see it counted up to 5 before the error was small enough that the ECU was happy again so it start counting down again.  If that error accumulator gets up to 100 then it will go into safety mode and shut down the throttle.  The highest accumulator we see in that log is 5 so you are a long way off safety mode with normal driving but is possible with much more on/off throttle action in a race situation that could count up much faster.

You could try the 1UZ PID settings from the help file and see if they help.



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So my initial throttle fault was before i got the vehicle mapped and it was when i was initially wiring everything up and getting things to work before mapping. I had my TPS sub and main to different inputs, and my AP sub and main to different inputs, but whenever i tried the auto calibration of both it would always fail on the TPS calibration when comparing sub and mains, i played around with the PIDS for around 4 hours to try get it to calibrate but it wouldn't, so i wired both inputs into just the one sensor on the throttle body sensor and it calibrated straight away, so i left it this way as i presumed i had a faulty sub or main sensor in the throttle body.

When my throttle faulted it left me stranded in the middle of the track, so i quickly reset the ecu with ignition and it cleared the fault, but then it happened again next run aswell, and it always did this in 3rd gear under heavier load at lower rpm, if i changed to second and stuck it higher in the rev range, say 5000+rpm, it would be fine. I only presumed it was a throttle fault as i had a throttle fault code show up and e throttle relay shut down, but due to my panic i didn't look into the code (wishing i would have checked the codes and just red flagged the session now) but it definitely came up with a throttle fault aswell as the e throttle relay shut down as i saw it in the little fault preview bar at the top of my tablet but i didnt register what fault code it stored (running one as a dashboard)

I guess that throttle target error accumilator might make sense, as it would build up errors until 100 where it would shut down. I will try inputting the 1uz basemap throttle PIDS and maybe go for another run and take another log and see if the target errors stop accumilating. I would also like to try putting my sub and mains back to separate inputs and try re-calibrating, i'm just worried it will completely mess the map up all together seems as my main tables seem to be tuned to APS

Either way i will try the 1uz basemap PIDS tonight and take it for a run and take a data log. With the throttle PIDS, i take it higher numbers mean more aggression to reach target if that makes sense? So if i increase the propertional gain to a higher number, this will effectively make the throttle react quicker to the target its trying to achieve?

 I will try review the data and see if i can see the throttle accumilator faults build up and if the 1uz basemap PIDS has helped, although i can't see to be able to navigate the data log very well at the moment but i will try learn how to use it.

I've also just remembered that i started taking a data log from my tablet on one of my drift runs, and the throttle didn't fault or shut down, but the throttle was definitely fluctuating, you can physically hear it in my gopro footage too, so i will find this data log and upload it

Sorry for the essays and questions, i really appreciate all the help and advice!



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look up the wikipedia article for PID tuning. There is a gif on the page about half way down that changes to show the effect of increasing P, I and D values. Very roughly, P is how quickly it reacts (how quickly it applies motor current), I is the aggressiveness (how much current it applies), and D is like a smoothing filter. None of these descriptions is technically correct but it can be a lot easier to understand to this way than fully understanding the maths behind it.

I had noticed that your TPS response was a bit slow in general compared to your AP - about 200-250ms, which has got to be noticeable when driving. Here's the process i've used to tweak ethrottle PID's in the past (in case the 1uz settings dont give you the feel you want, or you just want to understand "why" a bit better):

without the engine running, set "run mode when stalled" to "run throttle"

set your ethrottle target table so AP0% = TPS20%, then interpolate up to AP100% = TPS80%. ie your TPS will only span between 20% and 80% open with full accel pedal travel. 

probably store the ECU config at this point. It gives you a safe point to return to if you have to cut power a abort testing later on.

go to the logging window in pclink, start a log, and make APS main and TPS main the only 2 parameters visible (or at least the only 2 in one of the groups)

press the accel pedal slowly a few times then quickly a few times, then quickly but only to 1/2 or 1/4 pedal travel and notice how much delay you see between the AP line and the TP line. 

now go to the ethrottle PID numbers and bump up P by 1 and repeat the tests. What you are looking for is minimal delay between the AP line moving and the TP line starting to follow it. At this stage dont worry about overshoot too much, just bump it up towards 8 or 9 until you stop seeing much improvement. dont go past 9 though.

Make some notes as you go about what numbers you are testing. If you get the throttle to the point its just oscillating and wont stop after a second or 2, turn the ignition off, start again at slightly less aggressive numbers. 

Now you basically play D off against I. D you increase or decrease by 1 or 2 points at a time. I by 0.02 or so. If the TP response looks "lazy" - ie its heading towards the AP line but starts to taper off before catching up to it (so TP gets to within 1-2% of AP and the takes a second to get the last bit), lower D until that tapering off point is really close to the AP line. If you see the TP line overshoot the AP line and oscilate a few times before settling down or if it doesnt stop oscillating at all, increase D until you only have no overshoot or maybe a single small overshoot then it stablises at the AP line. 

To evaluate I, looks at whether the angle of the TP line matches that of the AP line when you press the pedal. If TP isnt a sharp enough angle, ie its heading in the right direction but not steeply enough, increase I (by a tiny bit). If TP likes to overshoot the target/AP by more than a couple percentage points, then lower I a bit. Note: this is why you tweaked the throttle target table to between 20 and 80 - you cant normally see overshoot below 0 or above 100. 

You'll likely see overshoot worst when making large quick changes, and you'll see lazy response worse when making small slow changes. 

When you have numbers you are happy with, put the throttle target table back to its normal values and save everything.

Regarding the APS and TPS calibration failures, you can do this manually by hooking up all 4x sensors but leaving your existing voltage values in place, setting ethtrottle to "quiet mode" mode, and pull off your intake pipe so you can manually move the throttle blade. start a log, then press the pedal all the way down, hold it for a couple seconds, then release for a couple seconds. repeat 2 or 3 times. Now push the throttl blade all the way open and hold it, then all the way shut (you need to press it shut, they like to sit at 3-4% when left alone), repeat a couple times. Now add parameters to your log view for AN 1, 5, 6, 7 - these are the raw voltages from the APS and TPS sensors. have a look at the min and max values for each sensor and enter these manually into the APS and TPS calibration screens. Also note if either of the SUB sensors doesnt have a full range of travel (ie it flatlines above 70% or something), you need to enter the main% value when the sub% stops increasing if this happens too.

You should now be able to switch to "run when stalled" throttle mode and run another log, but this time look at APS main, sub, TPS main, sub, and you should see all 4 tracking between 0 and 100% together (subject to a littel bit of latency in the TP numbers depending on how well your PID's are tuned).

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Many thanks for all the replies!

Just one last quick question, how do i setup logging so i can see it live on a graph like CJ said so i can see TP main and APS main voltages? I've managed to set it up so i can take a log, then have to open it and can view it afterwards, is there any way i can log it on a window so i can view it live, then obviously i can make changes to the PIDs and see the changes taking effect?

I tweaked the PIDs and my throttle target table last night, i started by doing the auto calibration on the APS and TPS, then played with the PIDs until the APS main and TPS main looked more even when put on a graph together, and also tweaked my throttle target table so my AFR was around 15AFR on hot idle, but didn't get the chance to take the car out to test as obviously all my APS changes effect my fuel table too. I'm going to get my friend to sit passenger and take some logs and post them up this weekend. At least i have a basic understanding of what i can change if i do get any throttle issues on my drift day on monday. I will also try setting my throttle settings to the same as Adam posted in that image and take a log of that too. I think as long as i can tune it so my throttle target errors don't build up, i should be okay for monday, but i'm going to find a different tuner and get my map looked at afterwards anyway.

I've also set my oil pressure engine protection settings to similar as what is in the GP LIMIT description in the help settings, and populated the table so that the engine will shut off at say 5000rpm if oil pressure drops below 10psi etc

Thankyou for all the help and advice, makes buying a Link ecu worthwhile when i get support like this!

Kind regards

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click on the logging tab in pclink. Now when you go to logging > record you can see the log in real time. 

right click the graphs and select properties, then add/remove/move paramters until you get what you want on the graph. Heaps of things are recorded in the background, you're just choosing what to display at the time.

You can click the config or tuning tabs to get back to the default screen at any time without impacting the log capture. It will carry on in the background while you do other things. Just a note that no where in the log file will it show that you changed settings in the middle of the log, the car behaviour will just suddenly be different, so name the log something sensible when/if you save it so that there is some hint that the settings changed in the middle. Not helpful when you're looking for something a week later and your log has unexplained changes in the middle of it.


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