Throttle problems
Thread Starter
5th Gear
Joined: Apr 2018
Posts: 5
Likes: 0
Throttle problems
Hello there.
Brand new here. I have purchased a 2002 50th ann. It was wrecked pretty bad. Everything runs but the throttle does not respond. My question is after airbag deployment does this stop the gas peddle from seeing the electronic throttle on the throttle body? We are close to being able to drive it but this makes it a little tough lol. Any help would be appreciated.
Jack Shelton
Brand new here. I have purchased a 2002 50th ann. It was wrecked pretty bad. Everything runs but the throttle does not respond. My question is after airbag deployment does this stop the gas peddle from seeing the electronic throttle on the throttle body? We are close to being able to drive it but this makes it a little tough lol. Any help would be appreciated.
Jack Shelton
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Thread Starter
5th Gear
Joined: Apr 2018
Posts: 5
Likes: 0
Hello there I did it is P1516. talks about short in throttle actuator... I have looked at both the throttle peddle and the throttle body itself and do not see any damage. There was one wire pulled from the wiring harness at the computer (that was the side the car was hit on). Pin 32 and I believe this has something to do with the throttle I was able to back prob the harness and re attach the wire but still no throttle response.car runs perfect except for this problem.
Thread Starter
5th Gear
Joined: Apr 2018
Posts: 5
Likes: 0
Drifting
Joined: Oct 2002
Posts: 1,773
Likes: 66
From: SoCal
Hello there I did it is P1516. talks about short in throttle actuator... I have looked at both the throttle peddle and the throttle body itself and do not see any damage. There was one wire pulled from the wiring harness at the computer (that was the side the car was hit on). Pin 32 and I believe this has something to do with the throttle I was able to back prob the harness and re attach the wire but still no throttle response.car runs perfect except for this problem.
Did you perform the Diagnostic System Check-Engine Controls?
Go to Step 2
Go to Diagnostic System Check - Engine Controls
2
Are DTCs P1518 and P1221 both set also?
Go to DTC P1518
Go to Step 3
3
Is DTC P1221 set?
Go to DTC P1221
Go to Step 4
4
Turn OFF the ignition for 15 seconds.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the TP sensor 1 and the TP sensor 2 angle parameters.
Slowly depress the accelerator pedal to wide open throttle (WOT) and slowly return the pedal to the released position.
Does the scan tool indicate both angle parameters increasing as the pedal is depressed to WOT and decreasing as the pedal is released?
Go to Diagnostic Aids
Go to Step 5
5
Turn OFF the ignition.
Disconnect the throttle actuator motor harness connector.
Remove the air inlet duct from the throttle body.
Inspect the throttle body and the throttle plate for debris, damage, and tampering that could cause the throttle plate to bind. If debris is found, clean the throttle body and repair the source of contamination. If the throttle body and/or throttle plate is damaged, replace the throttle body. Refer to Throttle Body Assembly Replacement .
Did you find and correct the condition?
Go to Step 17
Go to Step 6
6
Manually, slowly open the throttle plate to WOT and return the plate back to the closed position several times.
Does the throttle plate move smoothly without binding in both directions?
Go to Step 7
Go to Step 14
7
Turn ON the ignition, with the engine OFF.
Manually, slowly open the throttle blade to WOT and return the plate to the closed throttle position while observing the TP sensor 1 and TP sensor 2 angle parameters on the scan tool.
Does the scan tool indicate both angle parameters increasing as the throttle blade is moved to WOT and decreasing as the throttle blade is moved to the closed position?
Go to Step 8
Go to Step 15
8
Turn OFF the ignition.
Disconnect the TAC module harness connector containing the throttle actuator control motor circuits.
Turn ON the ignition, with the engine OFF.
With a DMM, test the throttle actuator control motor circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 9
9
With a DMM, test each throttle actuator control motor circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 10
10
With a DMM, test each throttle actuator control motor circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 11
11
Disconnect the other TAC module harness connector.
With a DMM, test for a short between each throttle actuator control motor circuit and all other TAC module circuits. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 12
12
Turn OFF the ignition.
Reconnect the TAC module.
Connect a test lamp between the 2 throttle actuator control motor circuits at the throttle actuator control motor harness connector.
Turn ON the ignition, with the engine OFF and observe the test lamp.
Did the test lamp illuminate briefly when the ignition was turned ON?
Go to Step 13
Go to Step 15
13
Inspect for poor connections at the throttle actuator control motor harness connector. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 14
14
Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .
Did you complete the replacement?
Go to Step 17
--
15
Inspect for poor connections at the TAC module harness connectors. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 16
16
Replace the TAC module. Refer to Throttle Actuator Control (TAC) Module Replacement .
Did you complete the replacement?
Go to Step 17
--
17
Use a scan tool in order to clear the DTCs.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running as specified in the supporting text.
Does the DTC run and pass?
Go to Step 18
Go to Step 2
18
With a scan tool, observe the stored information, Capture Info.
Does the scan tool display any DTCs that you have not diagnosed?
Go to Diagnostic Trouble Code (DTC) List
System OK
Last edited by RedRiderZR1; Apr 29, 2018 at 08:46 PM.
Thread Starter
5th Gear
Joined: Apr 2018
Posts: 5
Likes: 0
P1516 has to do with the PCM and TAC module monitoring the % throttle opening. If it sees an out of range condition it sets P1516. Pin 32 I assume is from the PCM, not sure which connector you found it open on (blue,red) but pin 32 from the blue connector is a Black/White wire that goes to Transmission Range Switch Signal A. The red connector pin 32 is a light green wire and goes to the MAP sensor signal. Somewhere between the PCM, TAC, and APP sensor, the car does not agree on throttle position. I am going to put in the Diagnostic Aids. A little tough to follow without the formatting, but the top Go to is the answer yes and the bottom Go to is the answer to no. Follow the numbers from there. Tac motor circuits need to be checked as well as TP sensor 1 and 2 voltages.
Did you perform the Diagnostic System Check-Engine Controls?
Go to Step 2
Go to Diagnostic System Check - Engine Controls
2
Are DTCs P1518 and P1221 both set also?
Go to DTC P1518
Go to Step 3
3
Is DTC P1221 set?
Go to DTC P1221
Go to Step 4
4
Turn OFF the ignition for 15 seconds.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the TP sensor 1 and the TP sensor 2 angle parameters.
Slowly depress the accelerator pedal to wide open throttle (WOT) and slowly return the pedal to the released position.
Does the scan tool indicate both angle parameters increasing as the pedal is depressed to WOT and decreasing as the pedal is released?
Go to Diagnostic Aids
Go to Step 5
5
Turn OFF the ignition.
Disconnect the throttle actuator motor harness connector.
Remove the air inlet duct from the throttle body.
Inspect the throttle body and the throttle plate for debris, damage, and tampering that could cause the throttle plate to bind. If debris is found, clean the throttle body and repair the source of contamination. If the throttle body and/or throttle plate is damaged, replace the throttle body. Refer to Throttle Body Assembly Replacement .
Did you find and correct the condition?
Go to Step 17
Go to Step 6
6
Manually, slowly open the throttle plate to WOT and return the plate back to the closed position several times.
Does the throttle plate move smoothly without binding in both directions?
Go to Step 7
Go to Step 14
7
Turn ON the ignition, with the engine OFF.
Manually, slowly open the throttle blade to WOT and return the plate to the closed throttle position while observing the TP sensor 1 and TP sensor 2 angle parameters on the scan tool.
Does the scan tool indicate both angle parameters increasing as the throttle blade is moved to WOT and decreasing as the throttle blade is moved to the closed position?
Go to Step 8
Go to Step 15
8
Turn OFF the ignition.
Disconnect the TAC module harness connector containing the throttle actuator control motor circuits.
Turn ON the ignition, with the engine OFF.
With a DMM, test the throttle actuator control motor circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 9
9
With a DMM, test each throttle actuator control motor circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 10
10
With a DMM, test each throttle actuator control motor circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 11
11
Disconnect the other TAC module harness connector.
With a DMM, test for a short between each throttle actuator control motor circuit and all other TAC module circuits. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 12
12
Turn OFF the ignition.
Reconnect the TAC module.
Connect a test lamp between the 2 throttle actuator control motor circuits at the throttle actuator control motor harness connector.
Turn ON the ignition, with the engine OFF and observe the test lamp.
Did the test lamp illuminate briefly when the ignition was turned ON?
Go to Step 13
Go to Step 15
13
Inspect for poor connections at the throttle actuator control motor harness connector. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 14
14
Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .
Did you complete the replacement?
Go to Step 17
--
15
Inspect for poor connections at the TAC module harness connectors. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 16
16
Replace the TAC module. Refer to Throttle Actuator Control (TAC) Module Replacement .
Did you complete the replacement?
Go to Step 17
--
17
Use a scan tool in order to clear the DTCs.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running as specified in the supporting text.
Does the DTC run and pass?
Go to Step 18
Go to Step 2
18
With a scan tool, observe the stored information, Capture Info.
Does the scan tool display any DTCs that you have not diagnosed?
Go to Diagnostic Trouble Code (DTC) List
System OK
Did you perform the Diagnostic System Check-Engine Controls?
Go to Step 2
Go to Diagnostic System Check - Engine Controls
2
Are DTCs P1518 and P1221 both set also?
Go to DTC P1518
Go to Step 3
3
Is DTC P1221 set?
Go to DTC P1221
Go to Step 4
4
Turn OFF the ignition for 15 seconds.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the TP sensor 1 and the TP sensor 2 angle parameters.
Slowly depress the accelerator pedal to wide open throttle (WOT) and slowly return the pedal to the released position.
Does the scan tool indicate both angle parameters increasing as the pedal is depressed to WOT and decreasing as the pedal is released?
Go to Diagnostic Aids
Go to Step 5
5
Turn OFF the ignition.
Disconnect the throttle actuator motor harness connector.
Remove the air inlet duct from the throttle body.
Inspect the throttle body and the throttle plate for debris, damage, and tampering that could cause the throttle plate to bind. If debris is found, clean the throttle body and repair the source of contamination. If the throttle body and/or throttle plate is damaged, replace the throttle body. Refer to Throttle Body Assembly Replacement .
Did you find and correct the condition?
Go to Step 17
Go to Step 6
6
Manually, slowly open the throttle plate to WOT and return the plate back to the closed position several times.
Does the throttle plate move smoothly without binding in both directions?
Go to Step 7
Go to Step 14
7
Turn ON the ignition, with the engine OFF.
Manually, slowly open the throttle blade to WOT and return the plate to the closed throttle position while observing the TP sensor 1 and TP sensor 2 angle parameters on the scan tool.
Does the scan tool indicate both angle parameters increasing as the throttle blade is moved to WOT and decreasing as the throttle blade is moved to the closed position?
Go to Step 8
Go to Step 15
8
Turn OFF the ignition.
Disconnect the TAC module harness connector containing the throttle actuator control motor circuits.
Turn ON the ignition, with the engine OFF.
With a DMM, test the throttle actuator control motor circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 9
9
With a DMM, test each throttle actuator control motor circuit for an open or for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 10
10
With a DMM, test each throttle actuator control motor circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 11
11
Disconnect the other TAC module harness connector.
With a DMM, test for a short between each throttle actuator control motor circuit and all other TAC module circuits. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 12
12
Turn OFF the ignition.
Reconnect the TAC module.
Connect a test lamp between the 2 throttle actuator control motor circuits at the throttle actuator control motor harness connector.
Turn ON the ignition, with the engine OFF and observe the test lamp.
Did the test lamp illuminate briefly when the ignition was turned ON?
Go to Step 13
Go to Step 15
13
Inspect for poor connections at the throttle actuator control motor harness connector. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 14
14
Replace the throttle body assembly. Refer to Throttle Body Assembly Replacement .
Did you complete the replacement?
Go to Step 17
--
15
Inspect for poor connections at the TAC module harness connectors. Refer to Testing for Intermittent and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?
Go to Step 17
Go to Step 16
16
Replace the TAC module. Refer to Throttle Actuator Control (TAC) Module Replacement .
Did you complete the replacement?
Go to Step 17
--
17
Use a scan tool in order to clear the DTCs.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running as specified in the supporting text.
Does the DTC run and pass?
Go to Step 18
Go to Step 2
18
With a scan tool, observe the stored information, Capture Info.
Does the scan tool display any DTCs that you have not diagnosed?
Go to Diagnostic Trouble Code (DTC) List
System OK
Again thanks for taking the time to respond.
Jack Shelton
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