davidfarmer

so I'm all set to run my 05' at the track this weekend, and I come across a thread in the C6 Tech section. They say that if I run my track wheel (with no pressure sensors), the car will think I have a flat an either shut the car down, OR make extreme efforts to restrict my speed.

According to that thread also, if the TC is shut off, it will come back on.

The shop manual for 05 only mentions the warning lights, but does not tell me about actual performance restrictions.

I have LS2 edit on the way, and hopefully I can tune out any Torque Management (or disable the warning all together).

Anybody here (people I trust for track stuff) have any definitive info.

Dave

Oyishdog

make sure to disable the on star too!

AU N EGL

David the early '05s did not have that problem. Not sure what VIN was the change.

Try putting some track wheels on and drive down the road and back.

Z51_6SPD

Dave, I'm not one of your "trusted authorities" but here is what I know. Another autocrosser in our club bought a new C6 earlier in the year and has been autocrossing it without problems. He recently bought a second set of wheels (without pressure sensors)for a second set of aotucross tires. He was then unable to select"Competitive Driving" mode. The dash read out noted a flat tire with a caution to limit speed to 55mph. The computer did indeed limit his speed and handling characteristics. After consulting with our sponsor dealer they called GM Tech assistance for advice. GM said the computer requires input from all 4 pressure sensors in order to make "Competitive Driving" mode available. Without the 4 satisfactory pressure inputs the computer limits vehicle speed and enters a "safe" operating program until the (unsafe tire pressure) problem is repaired. GM also said there was no way to trick the system. Their suggestion was for him to install the 4 missing pressure sensors.
Tis all I know about this. I Hope it's useful.

Dale
North Florida Corvette Association

Kschwamy

Dave we had a brand new C6 Z06 come to the track this weekend and he broke the value stem and in replacing it the sensor was not replaced properly and the car believed it had a flat tire all the time and would compensate for that. He thought about the problem all night and duct taped the sensor to the rim and the car ran fine on Sunday and turned in some very impressive times.

RAFTRACER

David,
Yes this is very BIG problem with C6 and C6 ZO6. Haven't crossed this street yet , but I have been working on it. Myself and a certain gentleman who builds race wheels are thinking about putting all four sensors in a can that is sealed and pressurizing the can , then toss can in vehicle.
Or you could just install these sensors in track wheels, albeit expensive and needed "special" training equipment for new sensors.
I'm not looking forward to this crap on my new Z06 when I decide to buy.

davidfarmer

the whole point of my running the track wheels was to protect my stock wheels and tires. Even dismantling to get to the sensors risks damaging the wheels.

My 05' is a very early car, and I'll hope for the best. Tires just came in today, so I'll try and get them on the car tomorrow.

Dave

rbl

Wheel needs to be machined for the sensor ... not just a drop in issue.

RAFTRACER

I guess that would depend on if his track wheels were stock wheels or
not. If I remember correctly , you've been through this. What did you do ???? Is putting all of the sensors in a pressurized box inside the vehicle and viable option ?????

no spin

We had two C6's at Roebling last weekend, mine and a friend of mine. On the trip over one of his sensors quit on him. He was not able to enter Comp mode with the failed sensor. His vin was in the 1300's.

John Shiels

guess my C5 just went up in value

MattW_VA

Frankly, they all seem to behave differently.

Mine is a December build. If I drive 50 or so miles and the car can't see the pressure sensors it will turn on TC and keep your speed down. I can, however, still turn TC/AH off. Rex used to be able to do the same with his early C6 but he can't with his new one.

An additional note, I bring the stock rims/tires with me and the car is never the wiser. I don;t know the specifics on how/when it checks when the wheels with the sensors aren't in motion but I can say for sure that the car "sees" them.

Another interesting tidbit, with C5 Z06 rears and 285/35/18 Hoosier S04s and the stock C6 rims in front with 245/35/18 Hoosiers on it the car didn't balk at this setup if I left TC/AH on. With C5 Z06 rims and 305/30/18 GAC slicks all the way around the car almost immediately gets upset and turns on the TC. Strange beast.

davidfarmer

I'm bringing a square setup, 280 slicks all around. That's the best set of cheapos I could come up with quickly. I likely won't bring the stockers, as I'll be packed to the brim with 2 cars, a mule (kawasaki) and tools. If it works, I'll drive it, if not, I'll park it. Mine is an early car (Aug 04 production), so I've got my fingers crossed.

btw, LS2 edit can't write it out, as it is a BCM system, not PCM. However, I'm hoping maybe I can tweek the torque management if push comes to shove.

I wonder what would happen if I disconnect a wheel speed sensor? On a C5, this would shut down the entire TC and ABS system. I hate to lose ABS, but that's better than being artificially held back.

MattW_VA

Wow-August 04 is *early*. I think you should be good to go (I'm guessing you drive with TC/AH off-I don't think I even tried comp mode)

davidfarmer

the guy bought the car in September, so I'm guess August. Anyway, the car looks better than new, and I saved a good amount of money. I also liked the 05' as I can tune the engine myself, and their are lots of parts coming online. Supposedly, the 06' models have even more complex computer systems.

Honestly, so far, I do hate the electric door crap, and havn't figured out the memory seats/radio yet!

Mark VerMurlen

My way of dealing with this would be to buy an extra set of sensors and have them band mounted within the track wheels. You'll have to do the relearn each time you swap the wheels, but that won't take long once you've done it a few times. Its unfortunate that GM's software does what it does. Sometimes I think GM is trying to be "too smart".

- Mark

gonzalezfj

They are trying to protect themselves from sleazy product liability lawyers in any way they can.

MattW_VA

Unfortunately you can't train the C6 sensors with a magnet like you could with a C5, you have to have the RF tool (as far as I know)

acrace

From what I'm reading in this thread, without the sensors the car won't go into Competition Mode. Can you still turn everything (AH/TC) off without the sensors?

johninar

As was mentioned above, just carrying sensors would not do it. They would have to be pressurized or the computer would still report flat tires. Somehow the computer needs to be able to shut this feature off. I see a lot of unhappy campers with this problem.