What may cause the High Long Term Fuel Trim?

[q0987]

Hello all,

I have used the OBDWiz software to scan my 2000 Ford Taurus SE.

Issues found are as follows:

The Long Term Fuel Trim on both bank are too high ~14-20%.
The Short Term Fuel Trim on both bank look fine.

Can someone look in the attached data file and kindly give me some advice what I should do to fix the issues?

Thank you

Attachments:

• Temp2.zip

Topic

[college man]

if I’m reading the data right.your front bank o2 sensor
does not look like its switching rapidly. Your subtracting
fuel.could be spark related or the o2 is having a problem.
any check engine codes?

I moved your topic over to service and repair.You will
get more hits here. 🙂

[EricTheCarGuy]

LTFT is not as critical as STFT and it takes a while to correct after a repair or condition has changed with STFT. If you don’t have a CEL on with a code then I would not worry about it.

[q0987]

Hello Eric,

I just paid a local shop to inspect the car. They don’t find any issue so far. Thank you

[EricTheCarGuy]

You’re most welcome. Thanks for the update and for using the ETCG forum.

[college man]

Thanks for the update.

[Author]

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