dr_jekyll Posted November 8, 2008 Share Posted November 8, 2008 i have fitted a greddy emanage blue to my 4 jdm na-t the unit is adjusting the the afr as it should but it dosnt seem to stop the fuel cut . i have data logged the map sensor signal and the fuel cut occurs at 4.9v i tryed to set a volt clamp of 4.8v but still at WOT as soon as i move into possotive boost the car still hit fuel cut ? can anybody advise were i might be goin wrong , thanks Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted November 8, 2008 Share Posted November 8, 2008 First off are you using the greddy pressure sensor? and have you selected this to scale the maps by, including fuel cut? Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 8, 2008 Author Share Posted November 8, 2008 yes i am using the greddy 3 bar sensor i have ticked the box to say i am using it but i have not re scaled anything Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted November 8, 2008 Share Posted November 8, 2008 Ahh i think i see what you have done now, you say you have only clamped the voltage at WOT you should clamp it across the RPM range. Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 8, 2008 Author Share Posted November 8, 2008 i have clamped the voltage from 500 - 8000 rpm , its realy confusing me ??? Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted November 8, 2008 Share Posted November 8, 2008 Starting to sound like your fuel cut voltage is set to high then, have you tried it at a lower setting? Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 8, 2008 Author Share Posted November 8, 2008 yes , as i said earlyer i data logd the voltage and the cut occurs at 4.9v so initially i set it at 4.8 but even wen i set it at 3 jus tocheck it still happend. but the straige part was even with the limit set at 3v, wen i i looked back through the data the max voltage on the map signal still reached the 4.9 ?, the car was on a rolling road so we could adjust the setting as we were driving it. Quote Link to comment Share on other sites More sharing options...
Hermit Posted November 8, 2008 Share Posted November 8, 2008 I don't think the 'boost limiter cut setting' works when you're using the 'airflow output map'. So you end up doing it by hand in the airflow output map itself. This is the starting point I set up for my Soarer, which has fuel cut at 4.35V. There's three parts to it - 1) map greddy voltages to stock voltages, up to 0.9 bar (2.4V on the greddy) 2) clamp at 4.27V up to 1.3 bar 3) 5.0V out for higher pressures, which means I still have fuel cut protection at just over 1.3 bar. Note that I adjusted the scale on the left - it's not regular steps any more... If your fuel cut isn't at 4.35V you'd need to work out your own numbers, but hopefully that gives you the idea Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 8, 2008 Author Share Posted November 8, 2008 (edited) ok ill get the car back on the rollers on monday and see how we get on with that, thanks gents hermit wat engine code dose your soarer have ? Edited November 8, 2008 by dr_jekyll (see edit history) Quote Link to comment Share on other sites More sharing options...
Hermit Posted November 8, 2008 Share Posted November 8, 2008 hermit wat engine code dose your soarer have ? Engine code: 1JZ-GTE Airflow meter spec: TY_PR-1 Not sure how that helps you, but there you go Quote Link to comment Share on other sites More sharing options...
bromy Posted November 9, 2008 Share Posted November 9, 2008 IIRC you changed the standard map sensor for the tt item, I would revert back to the n/a item if you have not already and see how that goes. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted November 9, 2008 Share Posted November 9, 2008 I think it all hinges on what std sensor you're running, as thats the output you need to clamp, and then map higher using the Greddy sensor. Quote Link to comment Share on other sites More sharing options...
Ian C Posted November 9, 2008 Share Posted November 9, 2008 Mmmkay: 1) Just because you datalog 4.9v when fuel cut happens doesn't mean that's the threshold, that's just the maximum the sensor can spit out. The threshold is 1.0bar of boost, so clamping to a maximum of 0.99bar works nicely, and that's 4.40v 2) Don't try setting it to daft low numbers like 3v again Otherwise when you are at maximum boost your ECU will only be fuelling for about half that. 3) I'm assuming you have a stock TT ECU transplanted in? Would an NA have a fuel cut operation? Do the MAP sensor output voltages tally with the TT MAP sensor if indeed you have put one of those in? I assume you checked all that and didn't just drop one in and let god sort it out When you say the AFRs are right, how long does it roughly take to get back to stoich after a prod of the throttle - closed loop may be covering up a lot of sins... 4) The boost cut limiter table in the EMB only has one row, so you can't clamp it 'only for WOT'. And in fact you put the same voltage value in every cell anyway. 5) Your datalog will show different voltages for airflow depending on what part of the airflow system you are logging. The airflow *input* will show what the sensor is actually reading, the airflow *output* will show what you are sending to the stock ECU and that's the one you will be affecting. That value shows the adjustment value from your airflow map and will clamp at the fuel cut level if you reach it (which you shouldn't as then you'll be on 100% duty but thats another story). It doesn't, by the way, show any adjustments made by the global injector correction feature, so I'd avoid using that unless you want to confuse yourself. 6) I always thought the airflow output map was a really difficult way of doing things -Ian Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 9, 2008 Author Share Posted November 9, 2008 no i have the n/a ecu , and i am running the n/a map sensor again. the n/a ecu hits fuel cut as soon as i reconises the transition from vacume to posotive boost . so the i dea was to clamp the map signal before it hit the fuel cut and then usse the gredyy map sensor to tune the fuel after this point Quote Link to comment Share on other sites More sharing options...
Ian C Posted November 9, 2008 Share Posted November 9, 2008 Well in your datalog you need to find the voltage the sensor is putting out when you go first beyond atmospheric pressure and set the cut to just below that. -Ian Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 9, 2008 Author Share Posted November 9, 2008 that is exactly what we did , we ran the car on the rolling road an data logged all the voltages just before fuel cut , but even wen a clamp is set , the car still cuts, this is confusing me as i know of na-ts with the same hardware that have resolved the fuel cut issue . Quote Link to comment Share on other sites More sharing options...
Ian C Posted November 10, 2008 Share Posted November 10, 2008 Post up the datalog of that run and I'll have a look -Ian Quote Link to comment Share on other sites More sharing options...
bromy Posted November 10, 2008 Share Posted November 10, 2008 Ian, do you still have my datalogs to compare against? Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 10, 2008 Author Share Posted November 10, 2008 i will print them tomorrow and try and post them up , Quote Link to comment Share on other sites More sharing options...
Ian C Posted November 11, 2008 Share Posted November 11, 2008 Ian, do you still have my datalogs to compare against? Yep I've got them at home. Didn't you have the stock MAP sensor still? Quote Link to comment Share on other sites More sharing options...
bromy Posted November 11, 2008 Share Posted November 11, 2008 Yep I've got them at home. Didn't you have the stock MAP sensor still? Stock n/a map sensor and the greddy pressure sensor. Quote Link to comment Share on other sites More sharing options...
dr_jekyll Posted November 21, 2008 Author Share Posted November 21, 2008 (edited) just like to say a big thanks to all who gave me ther priceless info on how to get the na-t tuned and running properly , i passd on the info i gaind allong with the car to rollingmotion in cearphilly south wales , and i had it back today and it is fantastic , im verry pleased with the way it goes now , so one again , thanks for all the valuable info and experience , and a big thanks to rollingmotion , now im going to have some fun had fun , can anybody advise of a good quality well priced clutch:blink: Edited November 21, 2008 by dr_jekyll (see edit history) Quote Link to comment Share on other sites More sharing options...
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