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- - AFR mostly rich, erratic at times (https://www.ft86club.com/forums/showthread.php?t=86199)

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 .

Quote:

Originally Posted by aagun (Post 2216464)

Now ckeck ur long term and short term . Is should both at 0% and max for long term is 8% . Write the numbers . Drive the car . And log the both . Then if u have tach steam . Go to test injectors. And disconnect the direct injector . The fuel regulater will stop for 5 sec . The long term willl change . Log it

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 :respekt:

Quote:

Originally Posted by aagun (Post 2216466)

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.

Quote:

Originally Posted by aagun (Post 2216457)

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.

Quote:

Originally Posted by Koa (Post 2216472)

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 ):word:

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

so the LTFT will be +4.591%

Quote:

Originally Posted by Synack (Post 2216682)

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

Quote:

Originally Posted by aagun (Post 2216800)

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.

Quote:

Originally Posted by Synack (Post 2217152)

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

Quote:

Originally Posted by aagun (Post 2217516)

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.

Did you solve this issue?