Corolla SE Saloon 2002 1NZ-FE Swapped

[Xulfiqar]

There should not be a need to reset ecu, the trims self adjust themselves.

[hasankhurshid29]

As mentioned above, ecu was behaving irrationally. I disconnected O2 sensor and it doesn't even know that I disconnected it.
So that's why I reset it

[Xulfiqar]

So your afr pid kept on working with disconnected afr?

[hasankhurshid29]

No they were already stuck LTFT at 44%, STFT at 20%. And O2 voltage constant at 0.07V after disconnecting.

[Xulfiqar]

What scan tool was this?

[hasankhurshid29]

I am using the paid MotorData OBD app with generic chinese scanner. But because its a paid app, I can see majority PIDs without any issue.
Torque don't have that much PIDs

[hasankhurshid29]

It wasn't an issue with scanner as readings were updating but because the ecu was somehow stuck in a lean condition that's why the issue arises

[Xulfiqar]

My point is that these ecus dont get stuck, if there is a problem causing a rich or lean or abnormal condition, they will revert back to normal as soon as the condition is fixed. That last “revert to normal” is the confirmation of the fix, only after that the mechanic erases any errors.

What was the commanded afr when this anomaly was happening?

Btw, the chinese dongles for obd have very poor baud rates and poor refresh rate compared to a proper two way scan tool. And the app itself can also lockup due to the lag.

[hasankhurshid29]

I don't have PID for commanded AFR
And I don't think the ecu even have it
This ecu is for 2002 to 2004 Corolla Runx/Allex and they don't even have secondary O2 and Cat. And also no EGR present in those models

[Xulfiqar]

So you have the shit tastic ecu, got it.

Btw, these are not all the pids, pull up the maf sensor pid and log it as you drive. If the short term trim swings wildly, you have a bad maf.

[pwuser167013775514]

@hasankhurshid29 .
Brother i have certain questions regarding your transmission.
U340E.
As U340E transmission required ABS too for shifting and your car doesn't have ABS. You install VSS in transmission inplace of ABS input.

Is VSS works properly ?
Any problem you face due to VSS till now?
How is the performance of U340E transmission as compare to A246E transmission in term of shifting and jerks ?

[hasankhurshid29]

Yes VSS was installed
And at start, there was a speed difference in Speedometer and GPS speed but then they replaced a gear like thing which drives VSS and its now ok.
Also about shifting I don't think there is a difference between A246E and U340E

[hasankhurshid29]

Does anyone know a workshop having smoke machine in Karachi?

@xulfiqar
@capsat

[capsat]

not i know of am sorry

[hasankhurshid29]

I am getting P0171 System too lean code and car is not running properly
I thought it would be intake manifold leak or any hoses related to it.
But just checked the O2 readings and it is stuck at 0.2 at idle and when I accelerate to 1500 it barely reaches 0.32

So i think the Chinese O2 is now bad. So now I have to move back to Kabli

Also with higher rpms my LTFT jump to 40% and at idle it is 20%

What do you think?

@Hassan1991@xulfiqar @capsat @dani_kk @rajaatta

[capsat]

LTFT jump to 40% and at idle it is 20%

so far what i have learned from fellow 'members with day in day out ' dealing issue, the LTFT and STFT when added together produce the total fuel trim, and should 'NOT' exceed ± 10% in normal operating conditions. Fuel trims (LTFT, STFT, or LTFT+STFT) exceeding ±10% may indicate a problem in the engine or the sensors.

so i think locate a good O2 sensor from scrapyard near you. ' pay only ' subject to working as per scanner readings.

[Xulfiqar]

make sure there is no exhaust leak either,
also try to do a fake rich mixture, add some carburettor cleaner or LPG to the running engine, you should see a full rich condition pegged on the sensor.

and by default - we as professionals never use cheap unbranded parts for such critical application of an oxygen sensor.

[hasankhurshid29]

Can I use a Denso original part imported O2 sensor?

@Xulfiqar

https://www.denso-am.eu/catalog/part/DOX-0119

[hasankhurshid29]

I pour 3.7 liter of oil and then top up with the remaining 300 ml at 3000 kms. At 4000 kms, the oil on the dipstick is at lower mark. Is this much oil consumption can damage O2 sensor?

@Xulfiqar

[Xulfiqar]

No it wont.

But find out is the sensor actually biased lean first.