Reduced Engine Power
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Intermediate
Joined: Mar 2011
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From: Central S.C.
Reduced Engine Power
I cleaned the grounds underhood. The one on driver side was very dirty. I cut the plastic cover off and stripped the wires and soldered an eyelet and cleaned frame with wire brush,drilled hole and used self threading bolt to attach to frame. The passenger side looked new, so I cleaned it good, wire brushed frame and reinstalled. The car immediately seemed to do better. The gauges seemed to register quicker and the car seemed to crank quicker and run better. First time I stopped and restarted, there it was again. "Reduced Engine Power". Only this time there is a difference. It only does it about one time out of five, and I only have to turn key off and restart and it will be fine until next time. Another thing I noticed, when you turn the key on and wait for the little read out that says"Corvette by Chevrolet" to run across it will flicker. It only flickers if it is going to mess up. If it doesn't flicker, it will start and be ok. Thanks for all the help I know I am going to recieve. Mike
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
As much as I harp on how IMPORTANT it is to keep the grounds clean (and it is) your reduced power issue is most likely NOT ground related. The reduced power comes from a Throttle by Wire issue. All the circuits in the throttle control circuit are discreet circuits and fo not use a chassis type ground. It has a signal and a low reff return on the circuit card.
If you have a reduced power message,,,, you have a related DTC.. Please read and post those DTCs,, If you have a LOT of them, clear them. As soon as the issue happens, read the DTCs without turning off the ignition.
BC
If you have a reduced power message,,,, you have a related DTC.. Please read and post those DTCs,, If you have a LOT of them, clear them. As soon as the issue happens, read the DTCs without turning off the ignition.
BC
Thread Starter
Intermediate
Joined: Mar 2011
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From: Central S.C.
Thanks Bill. I will read and post them next time it happens. One thing I forgot to mention is that it will also post a "service traction control" for a few seconds also, but always goes back to the "reduced engine power". Cleaning the grounds helped something. Before they were cleaned I would get the message evertime I turned the car off, but if I started turning car on and off it would start and be ok. Now it only does it about one time out of five and always starts after I turn key off and on one time.
Tech Contributor
Joined: Apr 2007
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From: Forney Texas
Thanks Bill. I will read and post them next time it happens. One thing I forgot to mention is that it will also post a "service traction control" for a few seconds also, but always goes back to the "reduced engine power". Cleaning the grounds helped something. Before they were cleaned I would get the message evertime I turned the car off, but if I started turning car on and off it would start and be ok. Now it only does it about one time out of five and always starts after I turn key off and on one time.
Listen to Bill. He's the man when it comes to electrical. I've seen bad TAC module voltage, dirty connectors at the throttle body, water invading the throttle body and a few other things cause this problem on N/A cars. Your codes will put Bill and others in a place to help you isolate the trouble.
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Joined: Jan 2010
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From: Bardstown KY
my friend, you are not alone. Some with me
http://forums.corvetteforum.com/c5-g...ency-help.html
GOOD LUCK
TONY
http://forums.corvetteforum.com/c5-g...ency-help.html
GOOD LUCK
TONY
Last edited by tony123; May 8, 2011 at 03:06 AM.
Thread Starter
Intermediate
Joined: Mar 2011
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From: Central S.C.
I tried to clear codes. 4 codes will not clear. 1-HVAC-BO338HC 2-BCM- BO502HC,BO507HC,and B2482HC. One thing is I have driven the car a good bit yesterday and today. It only did it one time yesterday and has not done it at all today. I'm thinking of driving car to Helen, Ga. tomorrow.
Bill - Per my post, My wife and I are thinking of driving Vette to Helen, Ga. tomorrow. This is about a 75 mile one way little get-away. Do you think there is a chance our Vette will leave us stranded? Ever since it started doing this, it has always started back up and was ok till next time I turned it off. Since I cleaned the grounds, it has only done it one time and started up immediately after about 30 seconds. If it goes up there and back with no problem I will feel better. What do you think? I don't want to talk myself into something I will regret. A wrecker service up there would be several hundred dollars.
Bill - Per my post, My wife and I are thinking of driving Vette to Helen, Ga. tomorrow. This is about a 75 mile one way little get-away. Do you think there is a chance our Vette will leave us stranded? Ever since it started doing this, it has always started back up and was ok till next time I turned it off. Since I cleaned the grounds, it has only done it one time and started up immediately after about 30 seconds. If it goes up there and back with no problem I will feel better. What do you think? I don't want to talk myself into something I will regret. A wrecker service up there would be several hundred dollars.
Last edited by smithm31; May 8, 2011 at 01:11 PM. Reason: Additional text
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 77
From: Forney Texas
I tried to clear codes. 4 codes will not clear. 1-HVAC-BO338HC 2-BCM- BO502HC,BO507HC,and B2482HC. One thing is I have driven the car a good bit yesterday and today. It only did it one time yesterday and has not done it at all today. I'm thinking of driving car to Helen, Ga. tomorrow.
Bill - Per my post, My wife and I are thinking of driving Vette to Helen, Ga. tomorrow. This is about a 75 mile one way little get-away. Do you think there is a chance our Vette will leave us stranded? Ever since it started doing this, it has always started back up and was ok till next time I turned it off. Since I cleaned the grounds, it has only done it one time and started up immediately after about 30 seconds. If it goes up there and back with no problem I will feel better. What do you think? I don't want to talk myself into something I will regret. A wrecker service up there would be several hundred dollars.
Bill - Per my post, My wife and I are thinking of driving Vette to Helen, Ga. tomorrow. This is about a 75 mile one way little get-away. Do you think there is a chance our Vette will leave us stranded? Ever since it started doing this, it has always started back up and was ok till next time I turned it off. Since I cleaned the grounds, it has only done it one time and started up immediately after about 30 seconds. If it goes up there and back with no problem I will feel better. What do you think? I don't want to talk myself into something I will regret. A wrecker service up there would be several hundred dollars.
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Instructor
Joined: Jan 2010
Posts: 196
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From: Bardstown KY
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I agree.. None of those DTCs are causing you the problem. When the car has a bout of RP, IMMEDIATELY read the DTCs without turning off the ignition. Just pull up the DTC as its dieing and see whats there.
If you can clear the DTCs, and it cranks back up, I guess your fine.
Do any of the gages or door functions act up when the RP happens????
Ill PM you my number if you have a really bad time.
Good Luck on your trip.
BC
If you can clear the DTCs, and it cranks back up, I guess your fine.
Do any of the gages or door functions act up when the RP happens????
Ill PM you my number if you have a really bad time.
Good Luck on your trip.
BC
Thread Starter
Intermediate
Joined: Mar 2011
Posts: 28
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From: Central S.C.
Car made it to Helen,Ga. and back just fine, although I had a small issue. For those of you that never heard of Helen, Ga, it is a small German town up in the mountains of north Ga. There is a German tavern along main st. about every 100 feet. I forgot how strong this German beer is and as such my wife ended up driving us home with me sleeping in passenger seat. I have got to go to doctor tomorrow that is about a 100 mile round trip. I will drive Vette and see how she does. Thanks, Mike
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
The next time you see the reduced power message, do not shut the car off, pull the codes then and there. You can even pull the codes while driving down the road.
