Avanza Fluctuating Idle Problem

[cdabiog]

Owner po ako ng 2009 Toyota Avanza 1.3J. Normal po na sakit ng Avanza ang menor - nagwiwild yung RPM. Ang ginagawa ko lang po ay linisin ang ISC (Idle Speed Control) tapos tangalin ang negative terminal sa battery for 15 minutes para ma-ireset ang ECU.

Recently, nagka problem po ako sa fluctuating idle nya. Kapag tumatakbo ng mabilis tapos mag down shift or neutral, drop po yung RPM hanggang mamatayan. Nilinis na ISC and reset ECU ganun pa rin. Pinalitan na ISC ganun pa rin. Pinalinis na servo ganun pa rin. Pina diagnose sa casa wala nman problem sa mga sensor. Tune up na - palit air filter, sparkplugs, and change oil ganun pa rin. Malakas nman battery at hindi hard starting.

Hindi po mahuli yung problem. Sana po matulungan nyo ako. TIA

[miko101130]

pag nag aircon ka sir nag i-idle up ba?
anu normal nya na idle pag walang accessories and everything?

[cdabiog]

Nagiidle up naman pag Aircon. nasa 1000 pag naka-aricon 800-900 pag normal lang.

Meron kami suspect: Meron delay sa hatak nya. Bka sa throttle position sensor, cam position sensor, or VVT Variable Valve Timing Sensor. Any idea? Thank you Sir miko101130.

[K.I.L.L.]

Owner po ako ng 2009 Toyota Avanza 1.3J. Normal po na sakit ng Avanza ang menor - nagwiwild yung RPM. Ang ginagawa ko lang po ay linisin ang ISC (Idle Speed Control) tapos tangalin ang negative terminal sa battery for 15 minutes para ma-ireset ang ECU.

This is normal for an Avanza? That doesn't seem right man. Something must be wrong there. Did you ever drive your vehicle through a high flood?

[miko101130]

Nagiidle up naman pag Aircon. nasa 1000 pag naka-aricon 800-900 pag normal lang.

Meron kami suspect: Meron delay sa hatak nya. Bka sa throttle position sensor, cam position sensor, or VVT Variable Valve Timing Sensor. Any idea? Thank you Sir miko101130.

sa morning cold start ba mataas idle niya ? (normal process ito, mataas dapat idle for for a brief period sa morning)
Pag sensor sir meh problem most probably the CEL will illuminate, in your case wala naman CEL

nalinis mo na sir throttle body?

[kinyo]

pacheck nyo po MAF (mass air flow) sensor ... kung minsan hindi nagbibigay ng error pero defective pala

[Aracad665]

Sir huwag po muna ninyo ireset ang ecu i test drive po muna ninyo hangang lumabas ang CEL tsaka ipa diagnose

[shelu]

try mo check ang TPS sir. just google how to do it. hope this helps.

[cdabiog]

pacheck nyo po MAF (mass air flow) sensor ... kung minsan hindi nagbibigay ng error pero defective pala

thank you kinyo. let me check on the MAF first...then post the results...

[cdabiog]

thank you shelu. nakahanap ako ng DIY on how to test TPS...

check on this site Avanzanation: THROTTLE BODY TOYOTA AVANZA

[red_888]

mga sir up ko lng.....got the same problem....

*cdabiog naayos na din po ba problem nyo sir?

[Eryong]

thank you kinyo. let me check on the MAF first...then post the results...

Hi cdabiog,

Matagal na pero nagok ba problem mo dito?
Thanks

[Eryong]

mga sir up ko lng.....got the same problem....

*cdabiog naayos na din po ba problem nyo sir?

red_888 nagok ba problem mo? I am having the same problem. Thanks

[mina_nuka]

Sir huwag po muna ninyo ireset ang ecu i test drive po muna ninyo hangang lumabas ang CEL tsaka ipa diagnose

+1
Do not destroy the evidence prior to and during the investigation.
Have you had the intake manifold vacuum checked with the engine running at idle both cold start and at normal operating temperature?
What was the fuel trim reading from the scan tool?

[barako ba ma]

Can you post a screenshot of the engine data from the scan tool? 9 out of 10 the problem can be determined from what the PCM has on its freeze frame data.