Help!my C6 Accelerated By Itself!!!!
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Joined: Aug 2006
Posts: 57
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From: Las Vegas NV
Help!my C6 Accelerated By Itself!!!!
Okay I just got my car back recently, motors nice and broken in. (Forged Stroker 402 APS Twin Turbo) Today while I was getting on the freeway I gave it some gas in 2nd gear, just for a moment to get up to speed and then let OFF the gas and while I was checking my blind spot the car surged forward for about 1.5 seconds. It scared the hell out of me, although i had enough time to look down at the DIC and it said "ENGAGE DRAG CONTROL ACTIVE" So I continue to drive with no issues. I stop the car turn it off and get something to eat. Get back in the car, I THINK I forgot to put the car in competitive driving mode. When I pulled out same thing, and in the same gear, 2nd gear. This time I got into 2nd gear, accelerated to about 4k rpm, let off the gas almost completely and it accelerated by itself for about 1 second, let off itself and then within about 1/2 of a second surged forward again for about 1 second. I noticed again the same message on the DIC. After this happened I turned the traction control back to competitive driving. I tried to get it to do it again today to see if I could try and see exactly when it is doing it but no luck, didn't do it again YET. So thank you all for your help with this matter. WHAT IS GOING ON??????????
Safety Car
Joined: Dec 2004
Posts: 3,565
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From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
i found this to be interesting, i may help with the "engine drag control active' message.
"This paper describes the development and implementation of an Engine Drag Control algorithm to improve vehicle stability performance. Engine drag can occur on low and high coefficient surfaces when the driver suddenly releases the throttle. If the engine drag force becomes larger than the frictional force between the tire and the road, the tires will break loose from the surface and slip. This could induce vehicle instability especially with rear drive vehicles on low-coefficient surfaces. The EDC algorithm has been developed to provide accurate control of the wheels. EDC will help reduce the yaw rate of the vehicle and thus achieve greater vehicle stability."
http://www.delphi.com/pdf/techpapers/2002-01-1217.pdf
"This paper describes the development and implementation of an Engine Drag Control algorithm to improve vehicle stability performance. Engine drag can occur on low and high coefficient surfaces when the driver suddenly releases the throttle. If the engine drag force becomes larger than the frictional force between the tire and the road, the tires will break loose from the surface and slip. This could induce vehicle instability especially with rear drive vehicles on low-coefficient surfaces. The EDC algorithm has been developed to provide accurate control of the wheels. EDC will help reduce the yaw rate of the vehicle and thus achieve greater vehicle stability."
http://www.delphi.com/pdf/techpapers/2002-01-1217.pdf
Race Director
Joined: Jan 2006
Posts: 18,396
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I don't think the EDC program is designed to accelerated the car under any condition, just maintain sufficient engine speed to keep the rear tires from compression braking into a slipping situation. Take the car to the dealer. This could be a symptom to a throttle motor or TP sensor issue.
Safety Car
Joined: Dec 2004
Posts: 3,565
Likes: 5
From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
I don't think the EDC program is designed to accelerated the car under any condition, just maintain sufficient engine speed to keep the rear tires from compression braking into a slipping situation. Take the car to the dealer. This could be a symptom to a throttle motor or TP sensor issue.
would it be possible that you are lifting right as the turbos have spun up ?
Team Owner
Joined: Jun 2001
Posts: 26,714
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From: Houston, TX
I don't think the EDC program is designed to accelerated the car under any condition, just maintain sufficient engine speed to keep the rear tires from compression braking into a slipping situation. Take the car to the dealer. This could be a symptom to a throttle motor or TP sensor issue.
Melting Slicks
Joined: May 2005
Posts: 2,231
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From: Brownsville Tx
Thread Starter
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Joined: Aug 2006
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From: Las Vegas NV
Drifting
Joined: Nov 2004
Posts: 1,923
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From: California
Its always nice to know someone at the dealer which are willing to help you in those situtations. Most Joe Blow service writer would void your drivetrain warranty in a heart beat, good luck with your car
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Team Owner
Joined: Jun 2001
Posts: 26,714
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From: Houston, TX
Safety Car
Joined: Jul 2004
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From: Wantagh,L.I. New York
Pro
Joined: Nov 2005
Posts: 672
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From: Sapulpa Oklahoma
I would doubt that the warranty is even an issue seeing the investment in the vehicle. Just sounds like some tuning issue with the turbos/wastegate/boost control and throttle position. Installer should be able to tune it out.
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
I don't know of any dealerships that will provide warranty service on a non-stock motor (at least if they want to keep a good working relationship with GM). If you have one that does...PM me.
Drifting
Joined: Nov 2004
Posts: 1,923
Likes: 62
From: California
He said he was taking it to a dealer....not that they would fix it under warranty.
I don't know of any dealerships that will provide warranty service on a non-stock motor (at least if they want to keep a good working relationship with GM). If you have one that does...PM me.
I don't know of any dealerships that will provide warranty service on a non-stock motor (at least if they want to keep a good working relationship with GM). If you have one that does...PM me.
Le Mans Master
Joined: Aug 2004
Posts: 5,259
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From: Monroe Township New Jersey
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
St. Jude donor in memory of jpee '14
The dealer can run a scan and look for a code relating to the throttle position sensor or drive by wire motor. He can also do a visual check of the motor. Most likely there will be a line of techs waiting for a test drive
The dealer can not trouble shoot the turbo installation & tune. Whereas, the tuner can check for normal codes as well as fix any problem relating to the turbos. Just to throw in another item ...... what are the specs of the cam in the motor? In any event good luck
Safety Car
Joined: Apr 2005
Posts: 4,769
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From: SFV CA
Pete, call me wen you figure this out. My car goes in the shop on Monday for the actuator swap...I'll let you know how that goes, keeping my fingers cross!
I sent Les a PM over at LS1GT0, just to get his feedback on the Forged units.
I sent Les a PM over at LS1GT0, just to get his feedback on the Forged units.
Thread Starter
Advanced
Joined: Aug 2006
Posts: 57
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From: Las Vegas NV
Well my mechanic can get a lot done, He's good at staying under the radar somehow. The cam is 227/223 .640 .636 on a 115. I'll check with my tuner after the car leaves the dealer too.
Brabus I'm sure you'll be happy
Brabus I'm sure you'll be happy
Intermediate
Joined: Feb 2007
Posts: 29
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When you let off the gas (and put the car in neutral) do the RPMS hang a bit, or do they go straight down to idle?
Hanging RPMS can be a symptom of the "cruise control effect." Basically, it can be a combination of your base running airflow being to high, or idle cracker airflow or follower airflow.
Basically, a tuning problem.
Kinda scary though!!
Maybe your car just WANTS to go fast.
Tech Member
Joined: Dec 2005
Posts: 80
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From: Claremont CA
If it says EDC active then it is active... There are some complex algorithms running here that could easily be affected by his mods.
I feel kind of in the dark here since this is the 1st I have heard of this. The SAE paper is really interesting.
Regards,
Melting Slicks
Joined: Mar 2005
Posts: 2,534
Likes: 118
From: Columbia, SC
I've had this happen and seen the same DIC mseesage when downshifting going into a corner, and not quite getting the RPMs matched. Scared the b'jeezus out of me the first time. My tuner said it can be turned of much like TC.