Car doesnt accelerate as fast anymore

Buzzkill247

Some CRC MAF cleaner, and maybe some throttle body cleaning is in order. Make sure to disconnect the neg term on the battery first. Even if you don't disconnect the plug from the MAF or the throttle body, still recommend going through the ECU reset procedure and make your ecu relearn a bit.

Accelerator Pedal Released Position Learning
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accelerator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time harness connector of accelerator pedal position sensor or ECM is disconnected.

OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.

Throttle Valve Closed Position Learning
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by monitoring the throttle position sensor output signal. It must be performed each time harness connector of electric throttle control actuator or ECM is disconnected.

OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.


Idle Air Volume Learning
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific range. It must be performed under any of the following conditions:

Each time electric throttle control actuator or ECM is replaced.

Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.

Battery voltage: More than 12.9V (At idle)

Engine coolant temperature: 70 - 100°C (158 - 212°F)

Park/neutral position (PNP) switch: ON

Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is started, the headlamp will not be illuminated.

Steering wheel: Neutral (Straight-ahead position)

Vehicle speed: Stopped

Transmission: Warmed-up
For A/T models with CONSULT-II, drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indicates less than 0.9V.
For A/T models without CONSULT-II and M/T models, drive vehicle for 10 minutes.


OPERATION PROCEDURE

With CONSULT-II
1. Perform EC-42, "Accelerator Pedal Released Position Learning" .
2. Perform EC-42, "Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-II screen. If
“CMPLT” is not displayed, Idle Air Volume Learning will not be
carried out successfully. In this case, find the cause of the incident
by referring to the DIAGNOSIS PROCEDURE below.
8. Rev up the engine two or three times and make sure that idle
speed and ignition timing are within the specifications.

Without CONSULT-II
NOTE:

It is better to count the time accurately with a clock.

It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has a malfunction.
1. Perform EC-42, "Accelerator Pedal Released Position Learning" .
2. Perform EC-42, "Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
13. If idle speed and ignition timing are not within the specification, Idle Air Volume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to the DIAGNOSTIC PROCEDURE below.