Vitz Idle Vibration on AC in traffic

[Thinking]

which oil are u using in your vitz? also how did mechanic clean the throttle body?

[Xulfiqar]

difficult answer? Saying to not disconnect the battery because its not a 1990s car is a difficult answer? - You want something like a cd70 repair?

and doing a battery disconnect on any modern car makes the ECU lose the learned fuel trim values and also reset all other learned values of ignition, MAF and automatic transmission too. (consider modern as post OBD2)

All of the above are critical data that is required by the repairing mechanic as it can point him/her/it/they (its 2022) in the right direction of diagnosis, e.g. if system was showing a lean issue but at 3500 rpm, that is a completely different ballgame than a vacuum leak at idle. - but disconnecting the battery means now the mechanic has to complete the ECU learning cycle (25kms) and then wait again - or install more tools to identify running data in raw form because the usable processed answer was lost by owner because someone told him to disconnect battery.

So please, dont oversimplify it to the first bosch EFI level which actually did require a main power pull (two fuse pull or battery disconnect as part of diagnosis/repair)

[Xulfiqar]

bigger question is why the throttle body was cleaned? cleaning can and does damage it.

[Thinking]

Just so you know that almost 99.999% of the mechanics in PK dont have an OBD2 scanner and if they do they cant even read or understand what it says.

dealerships ask absurd money for code reading so in actual PK environment retaining the codes for the mechanic to read and refer at a later stage is more or less futile.

[chinyoti]

Which paksitan do you live in?

This tiktok generation might not be literate but they know how to use fancy gadgets.

Everywhere shop has a scanner and can do your job for almost free.

If you only for a code read they charge you as low as rs.500

If you get the job done from them they only charge labour.

New cars even if you leave every thing else aside.

All those 660 dinkines roaming around are impossible to fix without these scanners.

Alot of issues go after changing sensors and using the car.

Battery reset doesn't always work.

[asadgitl]

Hi, i have same issue but i have fixed my own self. First of all check your engine RPM in idle without AC on. it should be around 700 to 750.
2- check your IAC idle air control value. TIP for test IAC value, disconnect AC relay or fuse , and turn on AC, if your engine RPM increases, its mean your IAC working fine. if no changes in RPM, you need to service IAC value sensor or replace. note here i consider your electric wiring from ECU to IAC is fine.
3- If IAC working and your engine RPM is increasing while disconnected compressor wires. now second test put back AC fuse or relay, check the RPM in idle with AC on, it should be around 750 to 850 max. , if RPM with on AC around 1000, you will have jerk while shifting from N to R or D, and on Break press, engine vibration. the reason is, Automatic transmission engagement ratio with RPM, at 1000, auto transmission is engaged, and when you press break, you are forcing engine to stop while automatic transmission in partially engaged with engine, and cause engine rpm down by break force. in such case you can also have failure your transmission.
Conclusion : the RPM should be about 700 to 800, in idle with AC and without AC, your can set engine RPM idle speed by loosen IAC value screw, and turning clock / anticlock . if required

[obthedesigner]

Hey brother, thanks for the detailed answer. However, it's 2009 model so it doesn't have RPM to test this stuff out.

[asadgitl]

I have even older model 2000, no RPM on dashboard, i am using OBD2 connector to monitor. in short you should check for service IAC value or replacement . IAC usually required service due to its mechanical rotation inside

[obthedesigner]

Ah I see .. I will look into it .. May I know which OBD2 Connector and Android app is gonna work with Vitz 2009 ? I checked Daraz and places but there are multiple and I'm totally new into this but always have a keera to get into stuff since I'm a web developer lol

[asadgitl]

Yes I’m using ELM327 two versions available Bluetooth and WiFi, it’s OBD2 is almost compatible with applications , well good to know you web developer, I’m IOT and micro controller programmer , the best application which I have installed on my din android car panel is Torque . Connecting Torque I have put some manual parameters in application to get connected, I’ll know you when ready for other OBD2 you can download from play store as well , here I’m sharing images for you

[Hassan1991]

Have you changed the elm327 AT commands for initialization?

[asadgitl]

Yes in Torque pro app, to work with Toyota platz. For vitz, Yaris also would required . Default app for Elm 327 in play store won’t require any AT to set.

[Hassan1991]

These cars don't need any special AT commands.
Elm327 at auto mode already programmed to initiate the communication step by step.
Try torque pro to work on 5 baud K line with special initialization sequence. It wouldn't work.
Android Application is just a median to send AT commands to elm327 nothing more.

[asadgitl]

well bro, i never got connected Torque pro until set AT initialization even in complete scan different buad rate. may be its depends on ELM firmware matter.

[pwuser165913676073]

hey brother, sorry I was too much swamped with the work load. In the mean time, I tried to search for the scanner but not sure if these would work so I would like to confirm with you: https://www.daraz.pk/products/elm327-wifi-v15-obd2-wifi-diagnostic-scanner-for-multi-brands-can-bus-as-same-as-elm327-wifi-i125694483-s1283726728.html?dsource=share&laz_share_info=31073577_100_100_445991_30029384_null&laz_token=8262315111ad0d75f4d72d023516568f

I asked them but they are not sure and have details related to ISO and Baud rate which I'm totally unaware of.

I checked local market but it's not available there so I had look through Daraz.

[pwuser165913676073]

Found this one and the seller says it will work Vitz 2009:

https://www.daraz.pk/products/new-obd-v21-mini-elm327-obd2-bluetooth-compatible-auto-scanner-obdii-2-car-elm-37-tester-diagnostic-tool-for-android-windows-i271863856-s1484991197.html?dsource=share&laz_share_info=31083352_100_100_445991_30039159_null&laz_token=f0da6ac68d5333fc9f51daa43edaf1e1

[asadgitl]

Hello bro, in fact the link you have shared is supported almost old to newer communication protocols. Most newer car ecu having CAN bus and I have tested works very well. For more concern you have to check which protocol is in your ecu reference with make model and match with elm protocol supported list .

[pwuser165913676073]

Not sure about that man, I found this link: https://www.obdadvisor.com/obd2-protocol-supported-vehicle/

And my port looks like attached images.

[Hassan1991]

Your car has CAN protocol. Elm327 2.1v will work.

[pwuser165913676073]

Thanks brother. I believe this would work too? https://www.daraz.pk/products/elm327-elm-327-bluetooth-obd2-scanner-elm-327-obd-ii-obd-2-obdii-i107198088-s1255544787.html?dsource=share&laz_share_info=31090009_100_100_445991_30045816_null&laz_token=af8a9f1e233c3c5d59b7a7c24baafe4f

The second link I shared above is kinda cheap so I'm having doubts whether it would be a good quality product or not.