Reduced Engine Power after a TB installation?
Thread Starter
Heel & Toe
Joined: Dec 2009
Posts: 19
Likes: 4
Reduced Engine Power after a TB installation?
Hello all.
Today I removed the original TB from my 2000 C5 and I ported it. After I got it done and installed I swiched the power on and the computer started to show the Reduced Engine Power message. I didn't start the engine.
I get the following codes:
P1516 Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance
P1120 = Throttle position sensor circuit
P1221 = Throttle position sensor 1-2 correlation
C1278 = TCS temporarily inhibited by PCM
It seems that every code is related to the TB. I used a autoglym to clean and polish the TB. Is it possible that doing it somehow destroyed the sensors? The computer gives the messages right away when the power is switched on.
Do you think that buying a new throttle body will fix these problems?
Today I removed the original TB from my 2000 C5 and I ported it. After I got it done and installed I swiched the power on and the computer started to show the Reduced Engine Power message. I didn't start the engine.
I get the following codes:
P1516 Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance
P1120 = Throttle position sensor circuit
P1221 = Throttle position sensor 1-2 correlation
C1278 = TCS temporarily inhibited by PCM
It seems that every code is related to the TB. I used a autoglym to clean and polish the TB. Is it possible that doing it somehow destroyed the sensors? The computer gives the messages right away when the power is switched on.
Do you think that buying a new throttle body will fix these problems?
Melting Slicks
Joined: Dec 2004
Posts: 2,847
Likes: 1,144
From: Sleepy Hollow- NJ
Before you go and buy one, do you know anyone else with a vette that will let you use theirs for a quick swap/test?
Porting the TB is only a good idea if you have experience, that's why most will just spend a few bucks and buy one ported from a reputable porter. Not worth the trial and error.
Good luck!
Porting the TB is only a good idea if you have experience, that's why most will just spend a few bucks and buy one ported from a reputable porter. Not worth the trial and error.
Good luck!
Thread Starter
Heel & Toe
Joined: Dec 2009
Posts: 19
Likes: 4
Before you go and buy one, do you know anyone else with a vette that will let you use theirs for a quick swap/test?
Porting the TB is only a good idea if you have experience, that's why most will just spend a few bucks and buy one ported from a reputable porter. Not worth the trial and error.
Good luck!
Porting the TB is only a good idea if you have experience, that's why most will just spend a few bucks and buy one ported from a reputable porter. Not worth the trial and error.
Good luck!
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
Make sure all the pigtails and wires 'snap ' when you put them on--Also make sure that the drive-by-wire- throttle was installed correctly--
The Traction control system uses the throttle to limit engine power if it's sensing you are spinning the tires--ALSO try dis-connecting the battery for at least 2-3 hors and let th ECM re-set itself--
PS :the throttle blade in the "rest position" should be slightly opened --not totally closed--if not you installed something wrong--
The Traction control system uses the throttle to limit engine power if it's sensing you are spinning the tires--ALSO try dis-connecting the battery for at least 2-3 hors and let th ECM re-set itself--
PS :the throttle blade in the "rest position" should be slightly opened --not totally closed--if not you installed something wrong--
Safety Car
Joined: Apr 2008
Posts: 4,831
Likes: 1,847
From: NJ
2025 C8 of the Year Finalist - Modified
2023 C8 of the Year Finalist - Unmodified
2022 C7 of the Year Finalist - Modified
2021 C7 of the Year Finalist - Unmodified
Also, make sure there is nothing "stuck" inside the throttle body holding the blade open. (This happened to my car about 2 weeks ago.)
