lepich Posted January 2, 2009 Share Posted January 2, 2009 Doing WOT, on 3rd , from very low speed, I've noticed this: Throttle Opening Angle , after being 100% for a couple seconds, dropping to 46-47% (I did not lift a pedal!), then goes back to 100%, in about 1 sec.. Car behaves exactly like it should if i really lift the throttle, and then push back again. This is happening only when I do WOT from a very low speed for given gear. Not every time though.. Running WOT from at least 2500 rpm works fine, no problems. I've attached a datalog screenshot.. Something wrong with throttle by wire, guess? Is this a common issue? can this be form a tune? There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
PeterJMC Posted January 2, 2009 Share Posted January 2, 2009 Probably your automatic transmission downshifting to 2nd gear and then back up to third. But I really don't know just trying to throw out an idea. Link to comment Share on other sites More sharing options...
Spec B Posted January 2, 2009 Share Posted January 2, 2009 Did you change the drive by wire map? MickeyD tuned my DBW map to to start closing above 6600 RPM (right before the shift). I have never seen what you posted above...but again, I am just a noob. Good luck and let us know what the cause is..I too think it is tranny related. Link to comment Share on other sites More sharing options...
mickeyd2005 Posted January 2, 2009 Share Posted January 2, 2009 Datalog both accelerator pedal position and throttle position sensor. It's not common but sometimes the DBW throttle does go bad. It can also be a bad tune if the DBW map was modified. Link to comment Share on other sites More sharing options...
lepich Posted January 2, 2009 Author Share Posted January 2, 2009 Thanks, accelerator pedal position will be logged as well. I've just received 1.0 mm pill, now busy with re-mapping WD.. BTW, what may help to spool turbo faster? I still getting full boot around 3400 rpm.. It could be earlier for a VF40, right? Any hints how to tune to spool it faster? There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
Gire Posted January 2, 2009 Share Posted January 2, 2009 sounds like the goddamn studder to me.... he does have an 05 after all. Link to comment Share on other sites More sharing options...
lepich Posted January 3, 2009 Author Share Posted January 3, 2009 studder? I was thinking this is something with a turbo hesitation.. In my situation, it is not. Correct me if I am wrong. Spec B, I did not change that map.. Bacically I use stage 2 map modified from Mickey'd stage 1. changed MAF, timing, boost, avcs, wd.. the rest is the same. There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
lepich Posted January 3, 2009 Author Share Posted January 3, 2009 Probably your automatic transmission downshifting to 2nd gear and then back up to third. But I really don't know just trying to throw out an idea. I never drive in auto or sport mode:-) only manumatic. There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
Infamous1 Posted January 3, 2009 Share Posted January 3, 2009 That is most likely the reason why your spool is slighty slower as well. Look at your WGDC's they are reflective of the low throttle input as well. You are definately not getting 100% throttle input/performance, more than likely you just can't feel it since the TC isn't locked up anyways. Link to comment Share on other sites More sharing options...
lepich Posted January 3, 2009 Author Share Posted January 3, 2009 That is most likely the reason why your spool is slighty slower as well. Can you tell what is "that" reason? The fact I drive in a manumatic mode? sorry, not sure I understand what you mean. As for a spool, I think with AT turbo does not have enough time to spool on low RPM. If I hit 100% throttle at 1.5-2K RPM, in one second RPM jumps to 3K because of TQ, and boost start to come. Do you think it is enough time for a turbo to hit full boost from a vacuum? Actually, I have not seen logs of 5EAT car with full boost at 2900, did you? As for a WGDC, here what it looks like now, after I've installed 1.0 mm pill. However, it is not completed yet. Mickeyd, speaking of DBW map, which one from these two? (see second attachment) There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
Infamous1 Posted January 3, 2009 Share Posted January 3, 2009 "That" Is your Throttle Opening Angle%. Stg2 5eat's I have tuned (in normal 70 degree temps) usually see full boost (17ish psi) at 3100-3200 rpms in third with a run started at 2K. However look at you boost built just shy of 3K it is also lower than it should be. Link to comment Share on other sites More sharing options...
lepich Posted January 3, 2009 Author Share Posted January 3, 2009 Oh, I see now. this strange throttle flutter happens not often, usually it stays 100% all the time I am pressing a pedal. Here is my usual log: (see attachment) Now , after I've got 1.0 mm pill, it boost earler.. Still overboost a little , working on WGDC . As for a throtle,will log accelerator pedal position , will see. There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
lepich Posted January 6, 2009 Author Share Posted January 6, 2009 Ok here is the update:I was able to catch it again, logging Pedal angle this time. Again, I've started from 1500 RPM, on 3rd.. As you'll see on a screenshot, 100% pedal, throttle jumps from 100 to 47 then to 100 again.. WTF??? There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
Guest Posted January 6, 2009 Share Posted January 6, 2009 Maybe you found thr stutter culprit. There was speculation, and at least one confirmed case where replacement of TB cured stutter. Link to comment Share on other sites More sharing options...
mickeyd2005 Posted January 6, 2009 Share Posted January 6, 2009 Ok here is the update:I was able to catch it again, logging Pedal angle this time. Again, I've started from 1500 RPM, on 3rd.. As you'll see on a screenshot, 100% pedal, throttle jumps from 100 to 47 then to 100 again.. WTF??? I don't own a 5EAT but I've never seen this happen in any of the 5EAT logs. I think your DBW throttle is going out. BTW, I forgot to add that you should log requested torque as well. That would rule out the ecu trying to change it on purpose. Link to comment Share on other sites More sharing options...
merchgod Posted January 6, 2009 Share Posted January 6, 2009 I would log "target throttle plate position". If this remains at 100% when throttle plate show 4x%, then there may be something mechanically wrong with your DBW. If it drops to match, then it is likely something funky in the throttle mapping of the tune. Link to comment Share on other sites More sharing options...
lepich Posted January 6, 2009 Author Share Posted January 6, 2009 BTW, I forgot to add that you should log requested torque as well. That would rule out the ecu trying to change it on purpose. Thanks to pointing on this. It should be something with ECU doing, as it happens only on WOT and on very low RPM, only on 3rd. And it start happening after I've moved to OP maps... There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
lepich Posted January 6, 2009 Author Share Posted January 6, 2009 Ok, "target throttle plate position" + "requested torque " will be logged from now. Will see soon. There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
NSFW Posted January 6, 2009 Share Posted January 6, 2009 Holy crap. That's nuts. Subscribed for explanation. There are a few more things you can log that might be interesting: "Fuel cut signal from AT" - might be indirectly related? "Request torque down VDC" - does your car have VDC? "Ban of Torque Down" - I have no idea WTF this is "Retard signal from AT" - If my transmission signaled this, I'd be insulted "Torque control signal #1" - sounds relevant "Torque control signal #2" - sounds relevant "Torque permission signal" - did something revoke your torque privileges? Consider removing all of the other tuning-related parameters while you focus on figuring this stuff out (timing, knock stuff, load, boost, WGDC, etc). Keep accelerator pedal position, throttle opening angle, RPM, and the stuff listed above (plus target throttle position and requested torque, those are very promising too). I have said more than once that logging would help find the cause of the "studder" problem and yet nobody has actually taken that idea seriously until now. You, sir, are the only hope. Link to comment Share on other sites More sharing options...
merchgod Posted January 6, 2009 Share Posted January 6, 2009 Why don't you post your throttle maps (requested torque and target throttle plate position) in the current tune that exhibits this behavior? Link to comment Share on other sites More sharing options...
lepich Posted January 6, 2009 Author Share Posted January 6, 2009 Why don't you post your throttle maps (requested torque and target throttle plate position) in the current tune that exhibits this behavior? I did.. See my #10 post. This is a screenshoot, but you can see the values.. NSFW, I'll try to do my best:-) This morning was not abvle to catch it, everything was normal.. Keep trying. There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
merchgod Posted January 6, 2009 Share Posted January 6, 2009 I did.. See my #10 post. This is a screenshoot, but you can see the values.. Well, those tables look OK, so it isn't tune related. I would find it hard to believe that it is something related to the factory tune (like the wgdc "freeze") as someone else would have already noticed this long ago. Are you tuning the original factory ROM or did you flash to a newer revision? Either way, what cal id did the original have and what is the cal id of the new ROM? Link to comment Share on other sites More sharing options...
lepich Posted January 6, 2009 Author Share Posted January 6, 2009 I do not know what the original cal Id was, as I had cobb AP v1 before, and , as i remember, it uses some generic stock map when you unmarry it. I'll look at my current cal ID, will post it here . BTW, just looked.. cal id? what is that? I see ECU ID on a learning view, see attached. I use mickeyd-> smitty69 modified stage 2 map. There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
LittleBlueGT Posted January 6, 2009 Share Posted January 6, 2009 "Retard signal from AT" - If my transmission signaled this, I'd be insulted Full tune of 68HTA, KSTech 73 MAF, Racer X FMIC and ID1000s................by the DataLog Mafia!!! Link to comment Share on other sites More sharing options...
lepich Posted January 6, 2009 Author Share Posted January 6, 2009 Actually, I can't find most of this coulmns on roamraider.. last definitions updated. NSFW, where did you get them? There are no bad people, just differeent. Link to comment Share on other sites More sharing options...
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