Operation CHARM: Car repair manuals for everyone.

Throttle Body: Testing and Inspection

Throttle Body Test

NOTE:
- Do not adjust the throttle stop screw It is preset at the factory.
- If the malfunction indicator lamp (MIL) has been reported on, check for diagnostic trouble codes (DTCs).

1. With the engine off, check the throttle cable operation. The cable should move without binding or sticking.

- If the cable operated OK, go to step 2.
- If the cable binds or sticks, check it and its routing If the cable is faulty, reroute it or replace it then adjust it. When the cable is properly adjusted, go to step 2.

2. Operate the throttle lever by hand to see if the throttle valve and/or shaft are too loose or too tight.

- If there is excessive play in the throttle valve shaft, or any binding in the throttle valve at the fully closed position, replace the throttle body.
- If the throttle valve and shaft are OK, go to step 3.

3. Connect the HDS or the scan tool to the data link connector (DLC).
4. Turn the ignition switch ON (II).
5. Check the throttle position with the HDS or the scan tool There should be about 10 % or 0.5 V when the throttle is fully closed and about 90 % or 4.5 V when the throttle is fully opened.

- If the throttle position is correct, check the throttle body for carbon deposits, and clean it if needed.
- If the throttle position is not correct, replace the throttle body.