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unfortunately its not feasible for me to mount a laptop in the car and do a full ecu log with verastuner while on track. the Aim can log Load, AFR, RPM, Timing, ect. i'll check ecu voltage on Aim
you can see in this video, that the 35:42 mark, the rpm signal drops completely and the TPS signal also drop. coolant and AFR signal didn't drop tho. my foot was still flat on the throttle at that point.
i dont remember and never really pay attention because i'm more concern with not crashing on track. does yours happen on track or on street? also mine seems to happen under WOT.
Almost identical. Happenes a lot at WOT.
Mine happenes on the street.
And I found fuel system status is 16, which is closed loop with fault, don't what that means
I'll uninstall Versatuner from my car. Just happened twice when Wot, first the tacho drops dramatically, and oil coolant light came on, which means ECU has lost power. Second time comes right after the first one revovers, but there's no dash light came on.
Check out this thread at floor 13 https://www.rx8club.com/series-i-eng...7/#post4900612
Last edited by Shaozhou Zhang; 10-01-2019 at 08:19 PM.
I don't understand how that would cause the RPM signal to drop to zero when the car is moving and in gear.
yeah i dont get that either, unless the ecu complete shot off or something, which is what it feels like some times. like the ignition key is turned off and turned back on really quick.
Maybe the TB/TPS switch is flaking out? I have a new TB that I can send you to try.
interesting thought, maybe it's the throttle sensor in the pedal, since it lost signal at the pedal also? FYI when i use obd2 protocol with AiM, the throttle meter on the video use TPS signal at the throttle body. but in the video above, i used rx8 gen2 protocol and that throttle meter on the video use TP signal at the pedal.
i'll take you up on that offer to borrow the TB if i can't figure out anything else.
i think there's a good chance it's battery related now. i have an odyssey pc680 battery. i was at track event this weekend, it was 37 degree in the morning and it took a few tries to start the car on e85, so that drained the battery a bit. through out the day i was getting engine cut off and it got more frequent with each session. then finally one session, it got so bad the engine died completely on track. i thought the motor was blown, checked the mirrors and didnt see any smoke and pulled over on the side of the track. tried to start the car but nothing happened, engine wouldn't even turn over. the key light on the dash was blinking rapidly, i didnt know what that means. while getting towed back into the pit, i decided to turn the ignition on and pump start it, and it ran. i was so relived the engine wasn't blown. after getting back in the pit and figured that the battery was so low and the alternator couldn't keep up with the voltage demand. i tested the alternator by disconnecting the battery completely and drive the car around the pit and it drove fine, but i think the power demand at WOT is too high for alternator to keep up on its own. so i took my buddys huge battery jump pack and strap it in the car and clamp the wires to the my battery in the car, basically running two batteries. went out on track and wow the car has never ran that good in a long time, not a single hickup. even the misfire CEL blink was a lot less. i ran the next day with the jump pack and the car ran awesome. the one time the clamp cam off when my helmet pumped it on the floor, the engine was cutting off on track. even though battery meter on the Aim said voltage as 14.
my friend Matt (HufflePuff) also had engine cut off a few times with VersaTuner, and i know he's running a mini battery also, but he as a good Lithium one, which might be why he experience less cut off than me.
Shaozhou Zhang do you happen to run a mini battery also?
Last edited by trackjunkie; 10-07-2019 at 01:13 PM.
i think there's a good chance it's battery related now. i have an odyssey pc680 battery. i was at track event this weekend, it was 37 degree in the morning and it took a few tries to start the car on e85, so that drained the battery a bit. through out the day i was getting engine cut off and it got more frequent with each session. then finally one session, it got so bad the engine died completely on track. i thought the motor was blown, checked the mirrors and didnt see any smoke and pulled over on the side of the track. tried to start the car but nothing happened, engine wouldn't even turn over. the key light on the dash was blinking rapidly, i didnt know what that means. while getting towed back into the pit, i decided to turn the ignition on and pump start it, and it ran. i was so relived the engine wasn't blown. after getting back in the pit and figured that the battery was so low and the alternator couldn't keep up with the voltage demand. i tested the alternator by disconnecting the battery completely and drive the car around the pit and it drove fine, but i think the power demand at WOT is too high for alternator to keep up on its own. so i took my buddys huge battery jump pack and strap it in the car and clamp the wires to the my battery in the car, basically running two batteries. went out on track and wow the car has never ran that good in a long time, not a single hickup. even the misfire CEL blink was a lot less. i ran the next day with the jump pack and the car ran awesome. the one time the clamp cam off when my helmet pumped it on the floor, the engine was cutting off on track. even though battery meter on the Aim said voltage as 14.
my friend Matt (HufflePuff) also had engine cut off a few times with VersaTuner, and i know he's running a mini battery also, but he as a good Lithium one, which might be why he experience less cut off than me.
Shaozhou Zhang do you happen to run a mini battery also?
The flashing red KEY light should be the immobolizer, but ended up to be a died battery.
That's interesting, I do notice that my altenator voltage drop after the car has warm up, from 14.0 to 13.5 or 13.6, and when the radiator fan turn on the voltage drop to 12.4 for a second, then return to 13.4. When the fan turns off the voltage will suddenly increase to 14+, max I have ever seen is 14.9, but also only for a second.
I have my altenator tested and it is fine.
My battery was replaced by Mazda Dealer. Has a CCA of 640.
Last edited by Shaozhou Zhang; 10-07-2019 at 06:10 PM.
looks like you have standard size battery. Matt and I have small mini battery. but maybe the batter could be going out. it should be 14 ish at idle and slightly higher when reved up 14.2-.3 ish
i also have a 3 piece underdrive pulley kit, smaller main pulley, same size water pump and smaller alternator pulley. so effectively slow down the water pump but keeps the alternator speed the same.
looks like you have standard size battery. Matt and I have small mini battery. but maybe the batter could be going out. it should be 14 ish at idle and slightly higher when reved up 14.2-.3 ish
i also have a 3 piece underdrive pulley kit, smaller main pulley, same size water pump and smaller alternator pulley. so effectively slow down the water pump but keeps the alternator speed the same.
I think my battery should be ok as it was replaced Feb this year.
I had some serious engine failures that didn't make sense. We would tune the car on the dyno and do 40+ dyno runs beating the crap put of it. Then we would go to the track and 20 -30 minutes into a session the car would randomly ping and break.
The only thing that was different on track is the electrical loading was way higher. With the tranny and diff cooler pumps and fans... and the high steering rack loads in twisty corners the battery voltage would drop and either cause an ignition miss or a lean out that would lead to a ping.
Going back to a full size battery and upping the cable sizes from the alternator to fuse box and from the battery to the fuse box helped and haven't had the problem since. I also rewired the crank trigger wires and moved them away from the other wiring and the coils to make sure there wasn't any interference.
What kind of voltage you got when the engine is fully warmed up? I think it has something to do with my alternator only put out 13 ish after warm up. But it is also weird that after delete VT from my car everything was back to normal, I’ll try to look for a bigger battery
voltage should be dependent on engine rpm, and rpm is lower when engine is warmed up. my volt at idle is around 14, any rpm higher than idle and volt is around 14.1-14.3
if you recently got a new OE size battery, then it's probably not battery related, could be alternator. while the engine is running, unplug the battery terminal and test the volt the alternator is putting out.
Last edited by trackjunkie; 10-09-2019 at 10:07 AM.
voltage should be dependent on engine rpm, and rpm is lower when engine is warmed up. my volt at idle is around 14, any rpm higher than idle and volt is around 14.1-14.3
if you recently got a new OE size battery, then it's probably not battery related, could be alternator. while the engine is running, unplug the battery terminal and test the volt the alternator is putting out.
Damn my alternator must be going out. I do not notice any noticable increase when reving up, if 13.6 at idel, revving it up might be 13.7 or no change. When I turn on full load (lights, speaker, AC, both fans, power seats and power windows, the voltage will drop to 11.9 ish,but battery light will not come on (power window is a huge drain of power). I'll think about upgrade to a higher output alternator.
But still, why has VT trigger this is still unknown, I did not do any performance related tune, just increase OMP output and changed fan trigger temp, waiting for reply from them, since I heared that the voltage is PCM controlled instead a voltage regulator (heard, may not be true.), they may have messed up with sth.
Lastly, won't unplug battery while the engine running cause any damage? I heard that you might blown fuse or fry the PCM.
Last edited by Shaozhou Zhang; 10-09-2019 at 10:26 AM.
all that definitely sounds like alternator, especially when you recently got a new battery. Autozone will do alternator test for free.
what are the options for better alternators out there? S2 alternator any better?
Autozone tested said it was fine, but it actually might not be.
I did some research, there's a brand called Iraggi, trying to dig more information about it, several people installed it and seemed happy.
Emailed VT about this issue, they say it might be their launch control, their original word is
"Perhaps our placement of launch control code in the memory conflicts with some existing functionality."
I also heard back from Iraggi, here's the quote
Hey There! Thanks for reaching out! We can build a 220 Amp direct bolt-on for you!.
Direct Bolt On - Just plug it up and enjoy!
180-220 Output @ Idle - Idle output highly dependent on your vehicles idle rpm & crank pulley diameter
Produces maximum output by 1200 engine rpm (some vehicles can be as low as 1000)
OEM Compliant Regulator
13.7v-15.5v - Voltage Range - Temperature compensation in the regulator will lower the voltage as the temperature increases
Includes Lifetime Warranty, Trade-In Program and your choice of any colors/designs!
Just let me know if have any questions or are ready to place an order and I can send you an invoice
ON SALE RIGHT NOW FOR $459 + shipping! (Normally $559)
I made a quick bracket last night to mount a bigger batter for now. It looks big but its only 5 lbs heavier than the smaller battery because it's lithium and has 1010 crank amp, lol. I have a race next weekend, so will see how well it will work. I have high hopes since the car ran great when I strapped the jumper pack in the car.
Emailed VT about this issue, they say it might be their launch control, their original word is
"Perhaps our placement of launch control code in the memory conflicts with some existing functionality."
I also heard back from Iraggi, here's the quote
Hey There! Thanks for reaching out! We can build a 220 Amp direct bolt-on for you!.
Direct Bolt On - Just plug it up and enjoy!
180-220 Output @ Idle - Idle output highly dependent on your vehicles idle rpm & crank pulley diameter
Produces maximum output by 1200 engine rpm (some vehicles can be as low as 1000)
OEM Compliant Regulator
13.7v-15.5v - Voltage Range - Temperature compensation in the regulator will lower the voltage as the temperature increases
Includes Lifetime Warranty, Trade-In Program and your choice of any colors/designs!
Just let me know if have any questions or are ready to place an order and I can send you an invoice
ON SALE RIGHT NOW FOR $459 + shipping! (Normally $559)
You might want to just try swapping to another oem alternator. Unless you are running additional cooling fans or other accessories... I have not had an issue with my stock s1 alternator on track, until it started to die, then replaced it and it is fine again.
btw, used oem is better than a cheap rebuild.
If you want, you can get the original parts to rebuild the oem one for about the price (or less than the price) of a generic reman, although I have not attempted that to see how difficult it is.
a HO alternator is going to saddle down a low torque engine, no way would I pay that much regardless
Pretty straightforward, new bearings (514/503), rectifier assy (520), and V regulator (510) should do it, about $290 if you have an active Motorsports account, but they also have an S1 reman listed there for only $152 (Part# N3H1-18-300R-0B). Think I’d take my chances on it instead. New is $392.
10-01-2019, 01:23 PM
