Corolla 141 rpm problem. NEED HELP!

[chandrasekara9]

Hi experts,

I have 2008 corolla 141 (not axio 141).I got an full engine tuneup 2 months ago. After that there was 2 problems.idle rpm was about 1500-2000 range for few days now it is settled.Next problem, when I release the gas pedal after accelerate ,engine come to the idle for about 2 seconds then engine raise upto 1500-1600rpm. If i shift to N at that time rpm come to 1000-1200 range.Then I returned to the garage and they did throttle calibration , zero point calibration and lot of things using scanners and techstream software for 5-6 hours.After that car was fine but sadly I was able to drive about 4Kms the second problem came again.

[iRage]

Where and who tuned your engine and who did the calibration ? 

Are you saying that the idle rpm was 1500-2000 after you tuned it up and then a few days after the tune up it became normal ? If this is the case the first problem could be because the ECU was reset and it was "learning"

[Davy]

Did the mechanic who did the tune up clean the throttle body by spraying throttle body cleaner directly onto it while the Idle Air Control Valve and Throttle Position Sensor were still plugged in? If yes, my guess is that your TPS or IACV has taken a hit. 

Get the TPS tested and IACV inspected visually to make sure it goes through its full range of motion when power is applied. 

[Twin Turbo]

T he MAF could be dead or with a bad connection.

[chandrasekara9]

I did all the thing at Wheel Masters at A/pura.The problem with the idle rpm was settled to 800-950 range at working temperature.But the second problem is still hating me.

Edited February 27, 2020 by chandrasekara9

[chandrasekara9]

thanks for your detailed info.

I wasn't there at the time of tune up.So I don't know how did they do it.If the problem is with TPS or IACV kindly tell me what should I have to do.

Edited February 28, 2020 by chandrasekara9

[Davy]

  On 2/28/2020 at 7:20 AM, chandrasekara9 said:

thanks for your detailed info.

I wasn't there at the time of tune up.So I don't know how did they do it.If the problem is with TPS or IACV kindly tell me what should I have to do.

Expand  

If the issue is carbon deposits causing the TPS to give incorrect readings or the IACV to get stuck, you might be able to get them cleaned with circuit cleaner, properly dry them and reinstall. 

In the mean time, make sure that vacuum lines have been properly reconnected after the tune up. It might be something as simple as a vacuum leak under compression. 

[iRage]

Well...I was leading to where Davy has been been detailed about. Sounds like a person who has no idea what he/she was doing did the tune up and messed up or incorrectly installed some sensors and/or some vacuum line.

 

[chandrasekara9]

Thanks lot friends.I will have a look at MAF,TPS,IACV .

Edited March 1, 2020 by chandrasekara9

[chandrasekara9]

guys, I have collected following details using torque pro android app 

when gas pedal is fully released,

relative throttle position 0%

throttle position (manifold) 15.69%

absolute throttle position B 47.45%

accelerator pedal position D 16.08%

accelerator pedal position E 31.76%

Are there any abnormal conditions?

 

 

 

 

 

 

 

[chandrasekara9]

When gas pedal is fully pressed,

relative throttle position 64.71%

throttle position (manifold) 80.78%

absolute throttle position B 99.61%

accelerator pedal position D 72.55%

accelerator pedal position E 89.02%