Toliski Posted September 30, 2018 Report Share Posted September 30, 2018 Hello guys the question here is, Can a voltage drop from 13.8v to 12v at WOT make a pistol to fail? No lean AFR spot at log Quote Link to comment Share on other sites More sharing options...
cj Posted September 30, 2018 Report Share Posted September 30, 2018 sounds VERY unlikely. Are you sure you have cause and effect the right way around? several things failing in an engine cause cause the alternator to stop, or an electrical fault may have caused a voltage drop and something that led to engine failure. Do you know why you had a voltage drop in the first place? What type of engine failure, what type of engine, and what RPM were you at when it failed? Quote Link to comment Share on other sites More sharing options...
Toliski Posted September 30, 2018 Author Report Share Posted September 30, 2018 1 hour ago, cj said: sounds VERY unlikely. Are you sure you have cause and effect the right way around? several things failing in an engine cause cause the alternator to stop, or an electrical fault may have caused a voltage drop and something that led to engine failure. Do you know why you had a voltage drop in the first place? What type of engine failure, what type of engine, and what RPM were you at when it failed? Well I tune it at dyno before a week clean of knocks. Yesterday I make a pull 4rth gear WOT, the alternator belt came off because was old at about 6000rpm (I saw it at logs) I keep WOT until 7500 then I left the throttle. Black smoke from exhaust, oil from vents. No lean afr spots no ignition changes. Dwell: 1zz coils 2.8 at 13.8v 3.2 at 12v Quote Link to comment Share on other sites More sharing options...
Ducie54 Posted September 30, 2018 Report Share Posted September 30, 2018 Do u have a log of that run that it blew? Quote Link to comment Share on other sites More sharing options...
cj Posted September 30, 2018 Report Share Posted September 30, 2018 it would make sense for it to run lean if it dropped to ~12v and your injector dead times were badly off for that voltage, and that might cause knock, but you would see the whole log go lean, and at high RPM dead times dont make that much difference. Knock control probably would have seen it too. If the log shows good AFR, and it also shows the timing to be sensible values, then i'd be looking at a mechanical failure in the engine. Oil and coolant level ok? head gasket maybe? Quote Link to comment Share on other sites More sharing options...
Toliski Posted September 30, 2018 Author Report Share Posted September 30, 2018 37 minutes ago, Ducie54 said: Do u have a log of that run that it blew? I have a log from ECU. 3 minutes ago, cj said: it would make sense for it to run lean if it dropped to ~12v and your injector dead times were badly off for that voltage, and that might cause knock, but you would see the whole log go lean, and at high RPM dead times dont make that much difference. Knock control probably would have seen it too. If the log shows good AFR, and it also shows the timing to be sensible values, then i'd be looking at a mechanical failure in the engine. Oil and coolant level ok? head gasket maybe? I was about to tune the knock control yesterday but I haven't that chance now. If the injector cut was very minimal just one or two injector events, the wideband can see that? Quote Link to comment Share on other sites More sharing options...
cj Posted September 30, 2018 Report Share Posted September 30, 2018 Can you post that log here so we can take a look? The injector wouldnt cut out from a voltage drop. it *might* run marginally leaner while the voltage was lower. If the dead times were set even close to correct you wouldnt see much change at 6000rpm. eg if your injector open time ms is at 20ms, and you have 1ms dead time @ 14v, and you drop to 12v where you have should have 2ms dead time , but you still only have 1ms because of incorrect settings, your fuelling would drop by around 5%. This should be noticeable in the logs. Quote Link to comment Share on other sites More sharing options...
Toliski Posted October 1, 2018 Author Report Share Posted October 1, 2018 https://drive.google.com/open?id=1CZWPJ8-BxtO6t8VlzCbw7OLfVKMR3ra- Here it is. The last run that i wot the 3rd and 4rth gear As I said before I was in the middle to tune the knock gain value so it's wrong for that log Quote Link to comment Share on other sites More sharing options...
Toliski Posted October 1, 2018 Author Report Share Posted October 1, 2018 And a guy said me a theory that I believe it, maybe the voltage drop affect my 1zz coils so there is no enough energy to produce good spark. Quote Link to comment Share on other sites More sharing options...
Ducie54 Posted October 1, 2018 Report Share Posted October 1, 2018 Are you running a methanol spray? Your IAT is all over the place. Can you post a map? Quote Link to comment Share on other sites More sharing options...
Toliski Posted October 1, 2018 Author Report Share Posted October 1, 2018 24 minutes ago, Ducie54 said: Are you running a methanol spray? Your IAT is all over the place. Can you post a map? No I don't have methanol my friend. I have an open element link IAT sensor I will send a map later. Quote Link to comment Share on other sites More sharing options...
Toliski Posted October 1, 2018 Author Report Share Posted October 1, 2018 5 hours ago, Ducie54 said: Are you running a methanol spray? Your IAT is all over the place. Can you post a map? https://drive.google.com/open?id=15vkv25q32uqt5YXLH9FEa3w2oC6eQi_n Quote Link to comment Share on other sites More sharing options...
iceman_n Posted October 1, 2018 Report Share Posted October 1, 2018 according to the log file IAT at 220kpa 7600 rpm is around 30 degrees quite ok in my opinion so i think advance timing blew the engine as the ignition degrees in my experience are high for turbo engine.... and obviously there is a problem with alternator and battery charging Quote Link to comment Share on other sites More sharing options...
Ducie54 Posted October 1, 2018 Report Share Posted October 1, 2018 39 minutes ago, iceman_n said: according to the log file IAT at 220kpa 7600 rpm is around 30 degrees quite ok in my opinion so i think advance timing blew the engine as the ignition degrees in my experience are high for turbo engine.... At 7.31 IAT is at 11 Deg, 7500 rpm, 216 KPA Almost looks like electrical noise. Quote Link to comment Share on other sites More sharing options...
iceman_n Posted October 1, 2018 Report Share Posted October 1, 2018 only at 7.31 has that temperature drop on intake and really suddenly Quote Link to comment Share on other sites More sharing options...
Ducie54 Posted October 1, 2018 Report Share Posted October 1, 2018 1 minute ago, iceman_n said: only at 7.31 has that temperature drop on intake and really suddenly Reason why? Quote Link to comment Share on other sites More sharing options...
iceman_n Posted October 1, 2018 Report Share Posted October 1, 2018 really i dont know, also it was under full boost, it start from around 50 degrees IAT and drop to 11 degrees really suddenly and i think it was the last full boost attempt as after that tps is at really low values propably it was the point the blew the engine that why you ask about methanol spray...its a reasonable reason for low IAT so suddenly Quote Link to comment Share on other sites More sharing options...
Ducie54 Posted October 1, 2018 Report Share Posted October 1, 2018 Yeah very strange that one. I reckon this hasn't seen a dyno or a knock listening device. Quote Link to comment Share on other sites More sharing options...
iceman_n Posted October 1, 2018 Report Share Posted October 1, 2018 if it sprays before IAT sensor....but he said he doesnt use methanos spray also what d you mean " Almost looks like electrical noise " Quote Link to comment Share on other sites More sharing options...
Ducie54 Posted October 2, 2018 Report Share Posted October 2, 2018 I would assume IAT would follow this trend. You can get electrical noise/interference when you run sensor wiring beside items like coils and alternators. At around the 6600rpm mark the IAT drops randomly. Not the reason why the engine blew but IAT should follow the trend like the pic. Quote Link to comment Share on other sites More sharing options...
iecku.tavea racing Posted October 2, 2018 Report Share Posted October 2, 2018 Some strange settings, but fuel seems to be fine. IAT´s are strange unconstant. Knock control isn´t setup as it should be! Can´t see, if it was knock related failure. However i think ignition timing is 3-4 degrees off, what i have seen to other high power 3sgte´s. Is the ignition timing matched between engine and ecu? Could you let us know more about the setup? Early Gen3 3sgte tend to blow the cylinder wall with forged internals. Quote Link to comment Share on other sites More sharing options...
Toliski Posted October 2, 2018 Author Report Share Posted October 2, 2018 8 hours ago, iceman_n said: if it sprays before IAT sensor....but he said he doesnt use methanos spray also what d you mean " Almost looks like electrical noise " 5 hours ago, Ducie54 said: I would assume IAT would follow this trend. You can get electrical noise/interference when you run sensor wiring beside items like coils and alternators. At around the 6600rpm mark the IAT drops randomly. Not the reason why the engine blew but IAT should follow the trend like the pic. 19 minutes ago, iecku said: Some strange settings, but fuel seems to be fine. IAT´s are strange unconstant. Knock control isn´t setup as it should be! Can´t see, if it was knock related failure. However i think ignition timing is 3-4 degrees off, what i have seen to other high power 3sgte´s. Is the ignition timing matched between engine and ecu? Could you let us know more about the setup? Early Gen3 3sgte tend to blow the cylinder wall with forged internals. Well guys, today I strip the engine to see the damage! About spray no I don't spray. About the IAT maybe was of the poor connection but if I remember it doesn't affect the timing at that point. Before a week I was on dyno and the fine is knock free. The timing is synced yes. I believe that the COP setup maybe run out of durable spark at 12v. What do you think about this? Quote Link to comment Share on other sites More sharing options...
Adamw Posted October 2, 2018 Report Share Posted October 2, 2018 55 minutes ago, Toliski said: I believe that the COP setup maybe run out of durable spark at 12v. What do you think about this? Coils running low on energy is just going to cause a misfire, it is not going to harm the engine. Toliski and iecku.tavea racing 1 1 Quote Link to comment Share on other sites More sharing options...
Sutkale Posted October 2, 2018 Report Share Posted October 2, 2018 According to the log files I see no reason for bad tune as reason for blown engine. What actually happen to the engine - no info on that. Is reference ignition ok? Quote Link to comment Share on other sites More sharing options...
iceman_n Posted October 2, 2018 Report Share Posted October 2, 2018 2 hours ago, Toliski said: Well guys, today I strip the engine to see the damage! does the piston have ignition marks on it or a bent rod ?? Quote Link to comment Share on other sites More sharing options...
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