TB swap problems
Thread Starter
Instructor
Joined: Feb 2008
Posts: 111
Likes: 0
From: Georgetown TX
TB swap problems
just swapped my stock TB for a ported one and im having problems i started it up and it wont idle right it keeps moving between 800-1200 and if i try to drive the car it goes into reduce engine power mode and just starts shaking any idea of what this could be thanks
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,126
From: Dyer, IN
whose throttle body did you install?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Check the throttle blade for smooth operation fully open to closed. When you release the TB it WILL NOT go full closed. Thats normal. There are TWO things that could be wrong. The motor that drives the TB isn't working correctly OR the variable resistor (throttle position sensor ) is bad or damaged. Make sure that all the wires, connectors and sensors are not damaged.
The reduced power is a result of the Throttle by wire system not being able to be in balance. One side of the TPS reads HIGH resistance while the other side reads LOW resistance. The Throttle Actuation Control Module compares the readings and if there not correct, it puts the PCM in Reduced Power mode.
Put your old TB back on and see if it works correct. If it does, I bet the TPS is bad.
BC
The reduced power is a result of the Throttle by wire system not being able to be in balance. One side of the TPS reads HIGH resistance while the other side reads LOW resistance. The Throttle Actuation Control Module compares the readings and if there not correct, it puts the PCM in Reduced Power mode.
Put your old TB back on and see if it works correct. If it does, I bet the TPS is bad.
BC
Thread Starter
Instructor
Joined: Feb 2008
Posts: 111
Likes: 0
From: Georgetown TX
ahh thanks im 100 percent positive its the tps just sent the girl friend to autozone im sure thats what it is as i heard a small crack when i put it on the new TB that didnt come with it i think i cracked it without noticing thanks so much!!!!!!!!
Thread Starter
Instructor
Joined: Feb 2008
Posts: 111
Likes: 0
From: Georgetown TX
couldnt get the part has to ship but im just worried that it could be something else the tps sensor that i have only has a small crack on the inside where the TB blade sits in could something that small cause it i mean it should still turn the blade and everything
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Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
Here is the relearning procedure that I used this week:
1. With the key off, remove the power connector to the TB motor.
2. Turn the key ON, but do not start the motor.
3. Wait 30 seconds, and then turn the key OFF.
4. Reconnect the TB motor power.
5. Turn the key ON, but do not start the motor.
6. Wait 30 seconds, and then turn the key OFF.
7. Start the car. The PCM initiates a relearn procedure.
1. With the key off, remove the power connector to the TB motor.
2. Turn the key ON, but do not start the motor.
3. Wait 30 seconds, and then turn the key OFF.
4. Reconnect the TB motor power.
5. Turn the key ON, but do not start the motor.
6. Wait 30 seconds, and then turn the key OFF.
7. Start the car. The PCM initiates a relearn procedure.