Fuel trims

[fastrs]

My short term fuel trim goes very rich around 2k and missfire with p0300 error.
What are the best values of short term fuel on idle
Screenshoot from Torque pro app elm327

 

[Antti O]

Ideal will be long term fuel trim 1 approx 0 and stft -/+ 5%

 

[fastrs]

I bought new oxygen sensors, precat and aftercat lambda, but without difference.

What else should look for? Air leak, injectors, fuel pump?

 

[Antti O]

I bought new oxygen sensors, precat and aftercat lambda, but without difference.

What else should look for? Air leak, injectors, fuel pump?

Positive LTFT means basically that there is too much fuel in standard settings. Ecu has to shorten injector pulse time.
It is running too rich, and ecu is leaning air/fuel ratio.
Try to look if there is any vacuum leak, or if you can measure fuel pressure.

 

[fastrs]

I bought new 4 coil packs, change precat lambda sensor, postcat lambda sensor, new spark plugs, cam sensor, cranck sensor still no difference.
Again dtc P0300 and P0313 come on. I need to testing injectors and cat, or maybe its vacuum leak somewhere or fuel pump

 

[turkie172]

That does not make sense the engine temp =90Deg but the screen shot says open loop due to insufficient engine temp.




Something to check a person on here had a misfire and it was the fuse box behind the left headlight which has the fuel pump relay.


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[TB Rich]

@turkie172 Hi, do you know which relay is the fuel pump one? - I've tried looking online before but never found what the exact location is? Cheers