Trackday Datalog - Hello Limpmode
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Trackday Datalog - Hello Limpmode
The G37 has one really aggravating flaw. It can't be driven on a track. If you run this car hard for more than 10min, it will go into some sort of transparent limp mode. No codes logged, no messages on the dash, just less power and a lower redline.
I've hit this on two separate track days now. One at about 80 degrees, the other at 65. Yesterday I took along my friend's ELM327 OBD interface and had my laptop logging data while I drove a session. Here's a link to the full chart of everything I was monitoring. (I also had it logging fuel trim, but those never changed)
http://gogogo.speakeasy.net/thrill/g...8/trackday.jpg
Video of a different session:
http://www.youtube.com/watch?v=Z1CKRVR3fmk&fmt=18
The whole chart looks pretty normal, and fits with what Chamelion logged on his. You get 88% throttle, and nothing more. You can tell when I'm on a straight because the orange line will go flat at 88%.
The interesting bit is towards the end:
You can see how the ECU all of a sudden cuts my throttle out and only gives me about 40%. Half of what you normally get. And for the rest of the run I never get back to that full 88%. Trust me, I'm still flooring it, it just won't give me full power.
I really want to know what causes this. To me its ridiculous that a car like the G37, which is sold for it's sporting pedigree, can't be driven hard on a track. Hell the brochure came with reprints of magazine track tests in it that actually talked about how the 335 overheated it's oil on the track, but the G37 was fine.
Clearly something is getting too hot. If I let the car sit for a while, it comes back to normal. It's not coolant, as you can see in the graph it stays right around 190 the entire time. Intake air temps stay around 150. My guess is that it must be oil temperature. But I don't have the hardware/software to read the oil temp sensor, if we even have one.
I've asked the dealership about this, but they want nothing to do with it. I wonder if I'd have any chance at getting infiniti corporate to do something. Maybe we need another oil cooler, maybe they can just fix it with a software update, I have no idea. I can say that I will sell this car next summer if I can't find a way to fix it.
Anyone else have any ideas, or know what it takes to measure oil temp?
I've hit this on two separate track days now. One at about 80 degrees, the other at 65. Yesterday I took along my friend's ELM327 OBD interface and had my laptop logging data while I drove a session. Here's a link to the full chart of everything I was monitoring. (I also had it logging fuel trim, but those never changed)
http://gogogo.speakeasy.net/thrill/g...8/trackday.jpg
Video of a different session:
http://www.youtube.com/watch?v=Z1CKRVR3fmk&fmt=18
The whole chart looks pretty normal, and fits with what Chamelion logged on his. You get 88% throttle, and nothing more. You can tell when I'm on a straight because the orange line will go flat at 88%.
The interesting bit is towards the end:
You can see how the ECU all of a sudden cuts my throttle out and only gives me about 40%. Half of what you normally get. And for the rest of the run I never get back to that full 88%. Trust me, I'm still flooring it, it just won't give me full power.
I really want to know what causes this. To me its ridiculous that a car like the G37, which is sold for it's sporting pedigree, can't be driven hard on a track. Hell the brochure came with reprints of magazine track tests in it that actually talked about how the 335 overheated it's oil on the track, but the G37 was fine.
Clearly something is getting too hot. If I let the car sit for a while, it comes back to normal. It's not coolant, as you can see in the graph it stays right around 190 the entire time. Intake air temps stay around 150. My guess is that it must be oil temperature. But I don't have the hardware/software to read the oil temp sensor, if we even have one.
I've asked the dealership about this, but they want nothing to do with it. I wonder if I'd have any chance at getting infiniti corporate to do something. Maybe we need another oil cooler, maybe they can just fix it with a software update, I have no idea. I can say that I will sell this car next summer if I can't find a way to fix it.
Anyone else have any ideas, or know what it takes to measure oil temp?
Last edited by Thrillhouse; 10-01-2008 at 05:16 PM. Reason: fixed link
#2
Sam Rothstein
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Hit limp mode last night while doing a canyon run... Totally a WTF?! moment... Revs were limited to 6000 rpms and didn't have full throttle til the car sat for about ten minutes after the run... Fricken sucks...
#3
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I track here in taiwan regularly but never had such problem. Our time attack sessions are about 20-25 minutes each run. (about 10-12 laps).. strange.. maybe we have a different ECU setup here in taiwan?
#4
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i took a G37 at streets of willow last year...it fared fine (the brakes stared to really heat up and fade as the day went on). of couse I only ran at 20 min intervals
#7
i think the braking problem will be resolved once some aftermarket pads start appearing.
the limp home thing though.. starting to sound like the 335i all over again lol. let's hope it's an easy fix.
the limp home thing though.. starting to sound like the 335i all over again lol. let's hope it's an easy fix.
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#9
Every Nissan car I've owned has a limp home mode. It says in the manual it is activated after a period of "aggressive acceleration and braking". It doesn't throw a code but it says that the "event is logged and can be retrieved by your authorized Nissan dealer for assistance when assessing warranty claims"
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I've tracked my car on 3-different days and each day I hit the limp home mode. I hit it earliest in the day when it was hot, later when it was cooler. I posted on this under "Engine cut-off at 6200 RPM" (actually the cutoff was around 6500). Thrillhouse, thanks for going the extra mile and getting the data. I hope it will help to finding a solution. I feel the same way about keeping the car. If it can't be fixed.... I'll take the loss and get something else. Does anyone know how we could get Infiniti to look at this??
#12
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I called Tadashi from Technosquare today. He said he had never heard of this issue before. He may be able to fix it if somebody is willing to bring their car in for a hard run on the dyno. He needs to induce the limp mode. Technosquare is in Torrance...310-787-0847. I dont have time to make it down there anytime soon or I would do it.
#14
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I called Tadashi from Technosquare today. He said he had never heard of this issue before. He may be able to fix it if somebody is willing to bring their car in for a hard run on the dyno. He needs to induce the limp mode. Technosquare is in Torrance...310-787-0847. I dont have time to make it down there anytime soon or I would do it.