AFR mostly rich, erratic at times

[Synack]

Originally Posted by aagun

Where are u from .. Worm weather ?

Di u have poping . While idle

Go rich cozed by air leakage after maf . Up to afr sensor. . . Or injectors failure by leaking fuel or reduce fuel rate .

Not sure what you mean by popping by I don't hear any popping.

It's been 60-80 degrees here in the past few weeks.

[Synack]

Originally Posted by aagun

Fuel rail should 450psi to 650psi at idles and up to 2000psi or 2800psi at wot

Those idle numbers are exactly what I'm seeing, I will check WOT to see if it's 2000-2800.

[aagun]

Originally Posted by Koa

not true, STFT and even LTFTs will vary above and below 0% if the system is operating as normal to account for variances in fuel quality and atmospheric conditions above what the car was tuned for

all your other advice is sound

we have to know what is hes ltft . should ecu try correction fueling maps

it happens to me , one of my DI failure by reduce inject fuel from the DI.
so that will insurance fuel trim.

ok for example.


if the car @ 3000 RPM with 14.7 AFR and 0% LTFT and 20% inj duty each . THAT means 14.7/4 inj = 3.675 AFR each .

if one of inj failure and have 3.0 AFR with same duty and RPM (engine load).
so then the total of AFR is 3.675*3 inj + 3.0*1 inj =14.025

the ECU try correct the fuel by adding fuel to all 4 inj until it stop at 14.7 AFR TOTAL .

SO ECU ADD FUEL BY THIS (14.7 AFR - 14.025 AFR) / 4 inj = 0.16875 AFR insurance each inj

it will be ( 3.675 AFR + 0.16875 AFR ) * 3 + (3.0 + 0.16875 AFR) = 11.53125 + 3.16875 = 14.7 AFR (ecu happy )

but the LTFT will be (0.16875 AFR /3.675 AFR) * 100 = 4.591%

so the LTFT will be +4.591%

[aagun]

Originally Posted by Synack

Not sure what you mean by popping by I don't hear any popping.

It's been 60-80 degrees here in the past few weeks.

poping is misfire

[Synack]

Originally Posted by aagun

poping is misfire

Haven't had any of that yet. Just crazy AFR's. I also just checked fuel rail pressure at WOT and it was upper 2000's, even hit 3000 once.

[aagun]

Originally Posted by Synack

Haven't had any of that yet. Just crazy AFR's. I also just checked fuel rail pressure at WOT and it was upper 2000's, even hit 3000 once.

what is your ltft at idle . better post here log data

[Synack]

Originally Posted by aagun

what is your ltft at idle . better post here log data

We've determined (Doug Wilks) that the tune is super old (>2 years) and over time the engine will run richer the more things start to settle and break in. So it's running super rich and needs a fresh tune. We did run logs with Ecutek and it didn't seem that the car had any issues, but we are still unsure of the erratic idle AFR's.

@Reaper and I installed the Moto East flex fuel kit yesterday and the Full Blown 485LPH fuel pump. I'm going to get the car fresh tuned for E85/93 any week now. Hopefully the new turbo and tune will fix everything.

[Dru670]

Did you solve this issue?