Another P1221 + Reduced Engine Power Issues thread
Thread Starter
Instructor
Joined: Feb 2003
Posts: 155
Likes: 0
From: Huntington NY
Another P1221 + Reduced Engine Power Issues thread
guys,
lately on my car i have been getting the p1221 code frequently while driving around. I will start with some info on the car, then move to whats been happening, then state what I think, then ask for help.
The car is a 97 coupe (36k miles) with a maggie, corsa exhaust, HID headlights, HUD, Z06 wheels, AVIC D3, and all factory options except auto climate and sport seats.
Whats been happening is when I drive around I am getting the P1221 code accompanied with the "reduced engine power" and "service traction control" messages. If i turn the car off, and turn it back on, it will sometimes go away for a while but then come back on. Lately, its been happening very frequently. It happened 4 times today.
After reading the forum, I have gathered alot of information. I know the issue is that the 2 TP sensors are not agreeing. I did try cleaning the factory ground connector on the drivers side frame rail in the engine bay but that didnt seem to help (I saw this mentioned on the forum.) Now, I'm thinking about buying a new throttle body assembly and swapping out the old one.
FWIW, everything else on the car works perfectly, so I dont think I have a grounding problem.
What I was thinking was trying to check the voltage across the individual TP sensors. I would have to track down which wires they are in the TB connector but that shouldnt be to hard. Its either this or get a new throttle body.
Anyone that has successfully gotten rid of this problem, please let me know how you did it and what you did to fix it.
TIA for any help
lately on my car i have been getting the p1221 code frequently while driving around. I will start with some info on the car, then move to whats been happening, then state what I think, then ask for help.
The car is a 97 coupe (36k miles) with a maggie, corsa exhaust, HID headlights, HUD, Z06 wheels, AVIC D3, and all factory options except auto climate and sport seats.
Whats been happening is when I drive around I am getting the P1221 code accompanied with the "reduced engine power" and "service traction control" messages. If i turn the car off, and turn it back on, it will sometimes go away for a while but then come back on. Lately, its been happening very frequently. It happened 4 times today.
After reading the forum, I have gathered alot of information. I know the issue is that the 2 TP sensors are not agreeing. I did try cleaning the factory ground connector on the drivers side frame rail in the engine bay but that didnt seem to help (I saw this mentioned on the forum.) Now, I'm thinking about buying a new throttle body assembly and swapping out the old one.
FWIW, everything else on the car works perfectly, so I dont think I have a grounding problem.
What I was thinking was trying to check the voltage across the individual TP sensors. I would have to track down which wires they are in the TB connector but that shouldnt be to hard. Its either this or get a new throttle body.
Anyone that has successfully gotten rid of this problem, please let me know how you did it and what you did to fix it.
TIA for any help
Tech Contributor
Joined: Jan 2007
Posts: 19,342
Likes: 1,123
From: Dyer, IN
guys,
lately on my car i have been getting the p1221 code frequently while driving around. I will start with some info on the car, then move to whats been happening, then state what I think, then ask for help.
The car is a 97 coupe (36k miles) with a maggie, corsa exhaust, HID headlights, HUD, Z06 wheels, AVIC D3, and all factory options except auto climate and sport seats.
Whats been happening is when I drive around I am getting the P1221 code accompanied with the "reduced engine power" and "service traction control" messages. If i turn the car off, and turn it back on, it will sometimes go away for a while but then come back on. Lately, its been happening very frequently. It happened 4 times today.
After reading the forum, I have gathered alot of information. I know the issue is that the 2 TP sensors are not agreeing. I did try cleaning the factory ground connector on the drivers side frame rail in the engine bay but that didnt seem to help (I saw this mentioned on the forum.) Now, I'm thinking about buying a new throttle body assembly and swapping out the old one.
FWIW, everything else on the car works perfectly, so I dont think I have a grounding problem.
What I was thinking was trying to check the voltage across the individual TP sensors. I would have to track down which wires they are in the TB connector but that shouldnt be to hard. Its either this or get a new throttle body.
Anyone that has successfully gotten rid of this problem, please let me know how you did it and what you did to fix it.
TIA for any help
lately on my car i have been getting the p1221 code frequently while driving around. I will start with some info on the car, then move to whats been happening, then state what I think, then ask for help.
The car is a 97 coupe (36k miles) with a maggie, corsa exhaust, HID headlights, HUD, Z06 wheels, AVIC D3, and all factory options except auto climate and sport seats.
Whats been happening is when I drive around I am getting the P1221 code accompanied with the "reduced engine power" and "service traction control" messages. If i turn the car off, and turn it back on, it will sometimes go away for a while but then come back on. Lately, its been happening very frequently. It happened 4 times today.
After reading the forum, I have gathered alot of information. I know the issue is that the 2 TP sensors are not agreeing. I did try cleaning the factory ground connector on the drivers side frame rail in the engine bay but that didnt seem to help (I saw this mentioned on the forum.) Now, I'm thinking about buying a new throttle body assembly and swapping out the old one.
FWIW, everything else on the car works perfectly, so I dont think I have a grounding problem.
What I was thinking was trying to check the voltage across the individual TP sensors. I would have to track down which wires they are in the TB connector but that shouldnt be to hard. Its either this or get a new throttle body.
Anyone that has successfully gotten rid of this problem, please let me know how you did it and what you did to fix it.
TIA for any help
Thread Starter
Instructor
Joined: Feb 2003
Posts: 155
Likes: 0
From: Huntington NY
I used the TPS from the new Throttle Body. I didnt change them out. What do you mean by DMM? I havnt done any checks.
I am going to get out my autotap tomorrow and see if I can get the voltage on the sensors.
I am going to get out my autotap tomorrow and see if I can get the voltage on the sensors.
Tech Contributor
Joined: Jan 2007
Posts: 19,342
Likes: 1,123
From: Dyer, IN
DMM= Digital Multimeter. Pretty much what your down to here....using the schematics and a DMM to isolate the issue.
Thread Starter
Instructor
Joined: Feb 2003
Posts: 155
Likes: 0
From: Huntington NY
I just went outside and happened to look at the front passenger side by the throttle body and found some wires that are damaged. Is it Okay to wire nut in a new section of wire to replace the current one, or should I actually solder in a new section of wire?
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