fiestacosworth Posted December 21, 2018 Report Share Posted December 21, 2018 Hi guys we have a evo 4 at work that has a weird issue that i just cant seem to find. the car has a link g4 plugin ecu. its a built motor etc gt45 turbo. loaded up base map and just checking basics ie injectors and coils boost solenoid valve etc all working ok. car starts and runs ok good idle. run it on the dyno to set up the fueling all fine. until it hits 4000rpm. and then the car just splutters like its hitting a limit of some sort. if i attempt a power run it starts fine then as soon as it hits 4000 the power just drops off does the splutter business and then builds up again. its not missfiring at all. i have logged it and uploaded the file. if you look you can see 100% throttle and 4000 you see the map goes up and down and this is the point its doing it. have also tried at lower throttle but as soon as it hits the 4000rpm it does it.. i have checked map limit. all correction tables etc. it sounds like antilag/launch is the best way i can describe it. it isnt mapped yet as want to find out what this is before anything else. as cant even get a run out of it with it doing this. i have also uploaded the map incase i am missing something. i am using a plex knock monitor and am not getting any knock either. have also disconected the boost solenoid and run direct from the turbo to the external waste gate to eleminate this and it still does the exact same thing. also has brand new plugs in gapped correctly. has an uprated fuel pump and injectors. the customer doesnt want massive power out of this so its not like we are ringing its neck. if you have a look at the log we are only get at around 0.7 bar of boost. any ideas guys ? as i said scratching my head evo base map.pclr Log 2018-12-20 11;38;58 am.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted December 21, 2018 Report Share Posted December 21, 2018 I dont see any obvious signs of trigger error, but the first thing I would try (assuming it is still an evo4 engine) is change the trigger mode to Evo1-6, rather than the evo7-9 mode you are presently on. Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted December 21, 2018 Author Report Share Posted December 21, 2018 Hi Adam. Sorry forgot to mention that. The engine fitted is an evo 8 “block and head” have tried the trigger settings on both 1-6 and 7-9 and it’s exactly the same. Quote Link to comment Share on other sites More sharing options...
jonnyt80 Posted December 21, 2018 Report Share Posted December 21, 2018 have you tested the fuel pump? i had the very same issue on an impreza GC8 this week Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted December 21, 2018 Author Report Share Posted December 21, 2018 Hi thanks for your reply. So you was receiving low fuel pressure at this point due to the pump ? I have not removed the pump to check it what was the issue with your pump ? Quote Link to comment Share on other sites More sharing options...
jonnyt80 Posted December 22, 2018 Report Share Posted December 22, 2018 the pump was failing to provide enough fuel as to why i have not tested it yet. when boost started to climb it was like fuel cut / boost cut. on removal it looked like the original. replaced it with an uprated version and the problem went away. the car started fine and ran ok off boost just would accept higher rpm/boost Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted December 22, 2018 Author Report Share Posted December 22, 2018 Ok so fuel starvation. I will hook up a fuel pressure gauge and check it. Customer told me it has a walbro unrated pump in there. But needs checking. I also read somewhere last night that the evos have a restrictor on the return line in the tank and it messes up the fuel pressure. So will have to check that also. Quote Link to comment Share on other sites More sharing options...
goddess7 Posted December 22, 2018 Report Share Posted December 22, 2018 boost gear wastegate trim table is -100% Evo4-8 default base map is -100% I'd like to fix this in the next update fiestacosworth 1 Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted December 22, 2018 Author Report Share Posted December 22, 2018 Ahh ok! So it’s applying 100% wastegate duty cycle all the time. Regardless of wastgate table! This could well be the issue! Why the hell would it be set to that as standard. We don’t have the gears wired in. So I can set this to 0 and just use the wastgate table. Quote Link to comment Share on other sites More sharing options...
JMP Posted December 22, 2018 Report Share Posted December 22, 2018 -100 wastegate trim wont cause it to break up like that, will just operate at wastegate pressure instead of higher boost. When you're tuning boost control you should be going through all the tables, I can imagine the -100 trim in there is more of a safety net so those that are blindly going about tuning don't grenade an engine Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted December 22, 2018 Author Report Share Posted December 22, 2018 I understand that. However this makes sense as to why we have no boost control. Any ideas yourself of what it could be causing the issue ? Quote Link to comment Share on other sites More sharing options...
JMP Posted December 22, 2018 Report Share Posted December 22, 2018 Nothing obvious in the log to me, it would be nice to see a log with AFR and fuel pressure. From the ECU statistics page it looks like this ECU has been in use for quite some time, so I'd be leaning towards more of a mechanical type issue, going back and checking the basics. I had a similar issue with a turbocharged 1zz many years ago, where it would hit what seemed to be a premature revlimit around the 4000rpm mark. For that one it was a trigger issue and I had to use the 1NZ trigger setting for it to work correctly Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted December 22, 2018 Author Report Share Posted December 22, 2018 The guy bought the car with the ecu fitted. And a blown engine. He supplied a new engine turbo etc and we installed in. It is annoying that lambda isn’t on there or fuel pressure. However when on the dyno we are running a wideband so can see what it’s doing and it’s ok. I do agree I need to perform a fuel pressure test to be sure it’s ok. When it happens the lambda reading goes rich - lean - rich - lean and then carry’s on smooth. Also we have 0 trigger errors so I ruled that out. Quote Link to comment Share on other sites More sharing options...
Phil Melvin Posted December 30, 2018 Report Share Posted December 30, 2018 tried checking on your Plugs buddy? mine last time, evrytime the boost climbs up, or hard step on the accel, would trigger the problem. some sort , a Boost cut? or fuel cut sounds alike. my pump also change to unrated walbro pump. , i change the settings to Open loop on the fuelpumpcontrol. Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted January 4, 2019 Author Report Share Posted January 4, 2019 Ok. So had some time on this evo today. And done a few changes. Changed the dwell of the coils to 2.5ms. Set the gearchange duty cycle table to 0. Checked the fuel pressure and fitted new plugs gapped to 0.5mm. All ok and running well.... however. Now if we try and adjust the boost up the car has the same problem that it had before of that bogging down and cutting. We cannot get it to run anymore than 1.1 bar or boost. It made good power at this. However cannot work out why we cannot run anymore boost. Fuel and ignition are good. Why can we not run anymore boost ? I have attached a photo of the run we managed to achieve. Any ideas as to what’s causing the issue guys ? Quote Link to comment Share on other sites More sharing options...
jonnyt80 Posted January 5, 2019 Report Share Posted January 5, 2019 have you tried using a manual boost controller to rule out the ecu contolled boost Quote Link to comment Share on other sites More sharing options...
neil brown Posted January 5, 2019 Report Share Posted January 5, 2019 What’s the map limit set to for overboost and what map sensor are you running ? Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted January 5, 2019 Author Report Share Posted January 5, 2019 Map limit is set to 320kpa. Map sensor is built in on board 4 bar that comes on the link xtream ecu. Not tried a manual controller no as we have control. Just can’t go over 1.1 bar of boost or it’s like there is a cut. But there are no limits set that low. Quote Link to comment Share on other sites More sharing options...
neil brown Posted January 5, 2019 Report Share Posted January 5, 2019 On your statistics max rpm is 11446 rpm Do you have a trigger issue ? also max map pressure is 280kpa so it has seen 1.8 bar of posistive pressure max Air temp input is 100’C that will pull boost Quote Link to comment Share on other sites More sharing options...
fiestacosworth Posted January 5, 2019 Author Report Share Posted January 5, 2019 The ecu has been fitted to the car for a wile and had another engine previous. This statistics are old. It hasn’t made that rpm or air temp or map with us running it. No trigger errors at all. Very confusing. Quote Link to comment Share on other sites More sharing options...
neil brown Posted January 5, 2019 Report Share Posted January 5, 2019 Reset the stats and then retest would the gear ratio table have anything to do with it if not using it, should it be all set to zero Quote Link to comment Share on other sites More sharing options...
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