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12 7 9 miles left when cornering at track speeds.

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Old Aug 7, 2009 | 06:38 PM
  #1  
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Legion5
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Default 12 7 9 miles left when cornering at track speeds.

This has never annoyed me in the past but I just reminded myself to post about this to investigate the issue.

Under very hard cornering (I forget which direction) the car sometimes reads no fuel in the tank on the fuel indicator and displays under 15 miles of fuel left in the message center.

I've replicated this at least a few hundred times. It only happens when I have less than a 3/4 tank and I corner very close to the limit.

The message center and fuel guage will read empty for 10 minutes after aswell before going back to normal which creates the issue of not knowing when i'm about to run out of gas.

Is this indicative of a potential problem for the car in the future?

Can the issue be eliminated?

It is a problem if I can't find out how much gas I have at the track, is there any way to get the guage to update better?

Has anyone had their fuel read empty while cornering.

Appreciate some discussion. I've been having a lot of fun with the car lately, I can regularly hit peak grip with it on asphalt back roads and it's all a blast. After work when I drive home I turn on the accelerometer and I can get 1.08 peak on every single of the 8 corners on my route. That's 9/10 and it's beautifully consistent.

Last edited by Legion5; Aug 7, 2009 at 10:36 PM.
Old Aug 8, 2009 | 09:17 AM
  #2  
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Taking a relatively long time to "recover" does not surprise me much. You get sort of the same thing if you fill the tank up while leaving the key in the 'run' position. If you want immediate update when the refueling is finished, you have to turn the key to 'off'.

Yeah, I know - that's not much of an option when you're between closely-spaced high-g corners.

I don't have my FSM handy, else I might know which direction was more susceptible to this fuel slosh problem. I can tell you from experience in a different car that it'll stumble before it'll quit, and the forward movement will keep the motor turning over (and the PS and PB operational) so don't declutch or toss it into neutral.


What you need to do is develop some feel for rates of fuel usage, i.e. how many laps or minutes per gallon when you're running it hard. As you have found out, while electronics are really good at some tasks (such as fuel and spark control) they aren't nearly so good at others. GIGO still rules.


Edit - as to the cause, bad or loose tank baffling? I don't have this problem in my '08. True, on the OE BFG 235/50 tires I'm not running all that close to 1g (probably 0.7-ish). But at under 1/4 tank I wasn't seeing this happen yesterday during an impromptu rear shock tuning session.


Norm

Last edited by Norm Peterson; Aug 8, 2009 at 09:25 AM.
Old Aug 8, 2009 | 11:53 AM
  #3  
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This has happened to me from hard cornering on the street a handful of times since purchasing the car new 3 years ago. I don't worry about it, it always corrects itself within a few minutes anyway.
Old Aug 8, 2009 | 12:19 PM
  #4  
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I like to throw my car into corners and I experience this frequently as well. It clears for me after a few min, or until it "reaches zero", or when I shut the car off.

A few months ago my dealer changed my fuel pump under warranty and the issue still did not resolve.
Old Aug 8, 2009 | 02:50 PM
  #5  
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the fuel level sensor does act weird. typically when I get gas I'm pretty low, I wait until the 50 miles left warning. so I pull up to the pump, shut the car off, fill up, drive off and the gauge climbs to full and no problem.

the other day I needed gas and my dog was in the car so I left it running with the AC cranking while I filled up. the car took the usual amount of gas it takes when it's empty but when I got in the car it only showed a little less than 3/4 tank. I reset all the things I usually reset like the trip counter and gallons of fuel used and the gauge never caught up. I even restarted the car and the needle just went back to where it was. it wasn't until the next day that it worked correctly.

the only thing I can think of is that it's not happy with sudden level changes while the car is running. similar to what you experience while cornering hard. it's dumb and shouldn't happen but at least it came back to normal and I didn't have to take it to the dealer. could be worse, three weeks after a guy I work with bought a Mini Cooper S he ran out of gas because the fuel sender got stuck at half a tank. finally he ran out of gas completely and it still showed half a tank, apparently that's a common issue on those.

Last edited by candymanjl; Aug 8, 2009 at 02:54 PM.
Old Aug 9, 2009 | 06:03 PM
  #6  
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That's just part of the fuel tank design, your experience is hardly unique. Half tank or less while autocrossing causes this to happen every time.
Old Aug 10, 2009 | 09:41 AM
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Originally Posted by Vapour Trails
That's just part of the fuel tank design, your experience is hardly unique. Half tank or less while autocrossing causes this to happen every time.
+1, I run my car with less then 1/4 tank while autocrossing. It never fuel starves but does give the warning sensor of low or no fuel left. I am surprised with all of your track experience and research you have yet to experience this.
Old Aug 10, 2009 | 05:35 PM
  #8  
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I agree. Happened to me at Pocono. On that clockwise track we ran, it would beep incessantly. I just gunned the throttle to drown out the beep It did however, clear at each subsequent ignition re-start.

As for consumption, I was using about 1/4 tank per 20-25 min session.
Old Aug 10, 2009 | 05:36 PM
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Happens to me all the time as well...annoying, yes, but part of the price to pay for playing.

At the track I make sure to reset the Fuel Used indicator when you fuel up. Despite wildly fluctuating needle indications the Fuel Used indicator is pretty much spot on.

And +1 to Norm's suggestion that you just get a feel for how much fuel you used and when it's time to pull her in for more.

Best,
-j
Old Aug 10, 2009 | 06:07 PM
  #10  
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After readng this thread I'm glad I ordered mine with the "plain jane" instrument panel. The guage works just fine.

I do try to keep the tanl at least 1/4 full when out "playing" to avoid risk of the fuel pump starving.



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