Toyota Passo 1.0 2011, Extremely Bad Fuel Average

[omersiddiqui5482]

As the title suggests our Toyota Passo 1.0 2011 is giving an average of 6 kmpl if the AC is turned on! Without AC the average is more than 12 which I think is still not good.

Before my brother had the car tuned it was giving about 16.6 kmpl average and was smooth. After the tuning, this bad average issue has developed. I am pretty sure that the mechanic didn't use any scanner before tuning.

I had the car scanned and it is not showing me any error codes recorded by the ECU. There is a little load on the engine when the AC is on rest the cooling is also good enough.

suggestions are required for immediate resolution.

@capsat @margallar @nnabeel @dayrider @syncview @Xulfiqar sb.

[dayrider]

Check fuel pressure. And ask your brother what he did for tuning. If they washed sensors, those might have gone bad

[omersiddiqui5482]

If the sensors have gone bad, there should be some warning indication on the cluster or an error code. but there isnt any @dayrider sir.

[dms664]

@rajaatta is 1kr specialist

[omersiddiqui5482]

@rajaatta sir, any suggestions / guidance

[dayrider]

And ask your brother what he did for tuning

Check fuel pressure, also accelerate hard and see the response of the car

[dayrider]

that is if they are dead, there is no warning in these cars when those malfunciton and make the car run rich or lean.

[omersiddiqui5482]

@dayrider sir, please guide how can i check these sensors... Let me again mention that the car average goes crazy bad on AC

[hassannabeel27]

that is if they are dead, there is no warning in these cars when those malfunciton and make the car run rich or lean

yes - how to check that o2 sensor is indeed giving correct readings ? Can we check rich/lean conditions independently without relying on car ECU scan tools?

[omersiddiqui5482]

It is not possible without a scan tool to get a proper reading.. Period

can these me check individually after being taken out is the question?

[nwzixh147]

check for fuel trims u can buy a cheap bluetooth scanner for around 2k it will be healthy for code reading and other minor issues

[Xulfiqar]

No they cannot!

Btw

May I ask

What was the need for tuning? Toyota has not made a car that needs regular “tuning” since the late 80s

Almost all are efi

[nwzixh147]

people here are stuck at 80s where the clean throttle body on every oil change oxygen sensor cleaning even maf sensor cleaning with carb cleaner

[dayrider]

Connect a scanner, go to live perimeters, and observe the fuel readings

[dayrider]

And in addition to this, please find out what they did to the car

[omersiddiqui5482]

@Xulfiqar sir, I don't understand for myself sir why was it tuned...

I guess since my brother wants to sell the car he was trying to have it serviced for the new owner ....

But now untill the issue is permanently resolved I am not going to sell it ..

The car was fine before the service it was giving about 17 kmpl without AC and with AC about 15...

There are no indications what so ever on the car...

@dayrider sir, I will be taking the car to the same guy tomorrow... To actually know what he did...

The thing about the tuning is correct have t had my Lancer tuned for about 2 years now, no issues just general maintenance

I should mention here that the average is quite down on AC, I had the AC refilled with gas like a week ago... The car does power down when the AC is turned on.. is there something wrong with the AC? I don't think it is the AC personally...

[dayrider]

Yes, if you overfill the gas, it puts extra load on the car

[hammad_hey]

might be gas is overfilled