System Too Lean - P0171 (FUEL CONSUMPTION ISSUES)

[rajaatta]

its fine please also consider the high mileage of the engine as well

[ahmedstudio]

Ok. But why is not engine reaching optimum operating temperature of 87 Centigrade. It is currently staying between 70-80 Centigrade. Engine mileage is 85000 km.

[rajaatta]

Were you using AC when taking the readings?
And what was the engine driving condition when you were taking the readings.

[ahmedstudio]

Yes I was using AC while driving and taking readings.
Egine driving conditions were rush and stop & go traffic

[RehanBhatti]

Thats why your engine temprature is 70-80 due to radiator fan which runs continuously with AC.

[RehanBhatti]

@rajaatta Sir g, what could be the reason of this extream lean condition. Engine is suzuki g10b. These readings are with AC on.
@ahmedstudio sorry to hijack your thread. I hope you will never mind.cheers

[rajaatta]

Dying fuel pump
Clogged fuel filter
And clogged fuel injectors would cause this situation.

[ahmedstudio]

Not at all. Indeed this is good, hope this thread can become an encyclopedia for fuel related issues with the expert advises of our fellows like Raja Atta, Zulfiqar sb and more.

Which app are you using for OBDII?

[RehanBhatti]

Raja sb, fuel filter has been replaced recently as well as injectors are being cleaned on cleaning machine.
So, fuel pump is giving up. Right?t

[RehanBhatti]

Its SZ Viewer. Its good for Suzuki G series engines.

[sleeper]

How is it connected to the car ecu frm ur phone? I am new to this, so its connected via some cable available at whch shop?
.
Also, lean condition means more air than fuel, right??...can this condition be same always and cause decrease in acceleration? Are u facing this?.....my cultus at 126k is facing low acceleration on petrol.......

[RehanBhatti]

You will need the following adaptor to connect your phone to your car's ecu via bluetooth.
https://m.aliexpress.com/item/32510856320.html?trace=wwwdetail2mobilesitedetail

[RehanBhatti]

There can be many reasons of decreased acceleration. You have to scan your ecu to get the fuel trims and any error codes.

[Xulfiqar]

and probably his thermostat is bad too.

[Xulfiqar]

how old is your oxygen sensor?

[ahmedstudio]

How can I check thermostat and rectify ?

[Xulfiqar]

what you are facing is overcooling. Your ECU is pretty dumb and not programmed to throw P0128.

The minimum temperature that your engine should see is the regulating temperature of the thermostat, - It happens quite a lot and is rectified by a new fresh genuine thermostat.

[ahmedstudio]

What is the optimum operating temperature for engine? Is it standard for all engines? Or is there a range?

I noticed today that the operating temperature if my car's engine is 81-85, 86 Centigrade and engine reaches this temperature after 2, 3 km of driving.

[Xulfiqar]

on these older toyotas its about 88 to 90C - on newer ones its 95 or so. - new benz, bmw and chev turbo engines have three different modes and temperatures depending on which mode is active.

mazdas and nissan are maintaining at 90C, subaru at 96C.

read the manual to get the figure

[ahmedstudio]

Your ECU is pretty dumb and not programmed to throw P0128.

How can ECU be dumb? Isn't it chips and wires, and logically programmed. I mean to ask what do you mean by dumb ECU.