Ok, before anyone slaps my hand, I searched, found, and thoroughly read:tongue::
http://www.nsxprime.com/forums/showthread.php?t=48505&highlight=overheating+track
http://www.nsxprime.com/forums/showthread.php?t=125245&highlight=overheating+track
http://www.nsxprime.com/forums/showthread.php?t=124601&highlight=overheating+track
http://www.nsxprime.com/forums/showthread.php?t=122405&highlight=overheating+track
and
http://www.nsxprime.com/forums/showthread.php?t=35953&highlight=overheating+track&page=1
That said, I didn't see an exact analog for my situation, and I'm frankly not entirely convinced they are related, but I wanted to get opinions none-the-less.
The Car:
Material to the problem:
-1992 NSX w/226,000 miles
-Stock C30A
-Stock milk-jug (recently replaced due to crack in previous stock milk-jug)
-Stock radiator/thermostat/pressure cap
(radiator could be original, as I have no receipt for replacement, thermostat, & pressure cap are new within a couple of years).
Mods (HIGHLY unlikely to be material to the problem)
-ARK cat-back
-baffled oil pan
-Dunlop Direzza Z1
-KW V3
-Dali "type Q" bars
-HP+ pads
The Track / Track Conditions
-Talladega Grand Prix (aka Little Talladega) www.tgprace.com
-I generally drive it in 2nd & third gear, although I discovered that driving it entirely in 3rd is no slower (Stock 5-speed).
-Vmax was ~110 in a couple of places running anti-clockwise. It's not a fast track.
-Dry/Sunny/windy conditions
-Ambient temperatures ranged between 50F & 70F (track temps unknown)
The situation:
In Session #1 (8:30am, pretty cool outside, 20 minute sessions)
-Following a warm-up lap, after 6-7 (~15 min or so) additional hot laps the car threw CEL 2 (Rear O2 sensor circuit).
-Seeing a CEL, I immediately pitted and parked the car while listening for any shenanigans from the engine. I did not check to see if it was in limp mode.
Session #2
-After about the same number of hot laps I again got the CEL.
-Knowing it was just an O2 code, I kept going for a couple of turns.
-At this time, the car began to get a bit hot. The stock water temp gauge would began to creep up fairly quickly.
-The temp gauge dropped back to normal after ~1/2 lap or less of 4th gear cruising ~3-4k RPM.
Session #3 (about noon-ish now, and measurably warmer)
-After clearing the code again and talking to my engineer (aka my dad on the phone ...automotive engineer), I went out again to see if I could run a session in warmer temps without throwing a code.
-I ran the entire session in 3rd gear, got about the same number of laps before the temp started creeping up, but this time NO CEL ?
Other notes
After this I just began running ~7 laps hard and then taking an early cool-down lap to avoid any over-heating condition, but I never saw a CEL again. The car was fine for the ~4 hour drive home as well.
-The kicker for me is that I was at this same track with the same car (on stock-size rubber and stock suspension) back in August when it was 90+ ambient and I had no issues at all unless I came off the track and let it sit for too long before turning it off.
-I'll occasionally catch a whif of coolant when I start the car and back out of the garage, but it leaves no puddle and the coolant level never changes. I understand this may be normal though as a result of the dump-tube location?
-I read in the other threads that a stock car will tend to overheat when pushed hard for a long period of time. While I was able to push harder (and maintain higher average RPM) since I was less held-back by too-small tires than on my previous trip, the percentage increase in overall average engine speed was probably minimal (especially running the whole track in 3rd).
http://www.nsxprime.com/forums/showthread.php?t=48505&highlight=overheating+track
http://www.nsxprime.com/forums/showthread.php?t=125245&highlight=overheating+track
http://www.nsxprime.com/forums/showthread.php?t=124601&highlight=overheating+track
http://www.nsxprime.com/forums/showthread.php?t=122405&highlight=overheating+track
and
http://www.nsxprime.com/forums/showthread.php?t=35953&highlight=overheating+track&page=1
That said, I didn't see an exact analog for my situation, and I'm frankly not entirely convinced they are related, but I wanted to get opinions none-the-less.
The Car:
Material to the problem:
-1992 NSX w/226,000 miles
-Stock C30A
-Stock milk-jug (recently replaced due to crack in previous stock milk-jug)
-Stock radiator/thermostat/pressure cap
(radiator could be original, as I have no receipt for replacement, thermostat, & pressure cap are new within a couple of years).
Mods (HIGHLY unlikely to be material to the problem)
-ARK cat-back
-baffled oil pan
-Dunlop Direzza Z1
-KW V3
-Dali "type Q" bars
-HP+ pads
The Track / Track Conditions
-Talladega Grand Prix (aka Little Talladega) www.tgprace.com
-I generally drive it in 2nd & third gear, although I discovered that driving it entirely in 3rd is no slower (Stock 5-speed).
-Vmax was ~110 in a couple of places running anti-clockwise. It's not a fast track.
-Dry/Sunny/windy conditions
-Ambient temperatures ranged between 50F & 70F (track temps unknown)
The situation:
In Session #1 (8:30am, pretty cool outside, 20 minute sessions)
-Following a warm-up lap, after 6-7 (~15 min or so) additional hot laps the car threw CEL 2 (Rear O2 sensor circuit).
-Seeing a CEL, I immediately pitted and parked the car while listening for any shenanigans from the engine. I did not check to see if it was in limp mode.
Session #2
-After about the same number of hot laps I again got the CEL.
-Knowing it was just an O2 code, I kept going for a couple of turns.
-At this time, the car began to get a bit hot. The stock water temp gauge would began to creep up fairly quickly.
-The temp gauge dropped back to normal after ~1/2 lap or less of 4th gear cruising ~3-4k RPM.
Session #3 (about noon-ish now, and measurably warmer)
-After clearing the code again and talking to my engineer (aka my dad on the phone ...automotive engineer), I went out again to see if I could run a session in warmer temps without throwing a code.
-I ran the entire session in 3rd gear, got about the same number of laps before the temp started creeping up, but this time NO CEL ?
Other notes
After this I just began running ~7 laps hard and then taking an early cool-down lap to avoid any over-heating condition, but I never saw a CEL again. The car was fine for the ~4 hour drive home as well.
-The kicker for me is that I was at this same track with the same car (on stock-size rubber and stock suspension) back in August when it was 90+ ambient and I had no issues at all unless I came off the track and let it sit for too long before turning it off.
-I'll occasionally catch a whif of coolant when I start the car and back out of the garage, but it leaves no puddle and the coolant level never changes. I understand this may be normal though as a result of the dump-tube location?
-I read in the other threads that a stock car will tend to overheat when pushed hard for a long period of time. While I was able to push harder (and maintain higher average RPM) since I was less held-back by too-small tires than on my previous trip, the percentage increase in overall average engine speed was probably minimal (especially running the whole track in 3rd).