Lean at idle STFT locked at 24+ with no AFR change

[jesus]

Reaching out to see anyone has gotten some type of resolution from my current lean idle issue.
The issue is very own minded it will come and go and seems to happen at first start up cycle and with some slight throttle input for a sec or two it will come back to its desired target I've taken some logs and will leave them down below.

I've gone through and done the whole check list of test to try and get this fixed
-pressure smoke tested system for 5 mins on warm engine no leaks
-clean/swapped out with known good MAF sensor
-cleaned air filter
-double check spark plugs/gaps all good
-PRV swapped with known good one( fuel rail pressure is still high so opt fuel for idle is achieved )
-purge valve blow/suck test passed ( pause )
-has a ntk primary o2 sensor with about maybe 10-15k miles on it ( believe its reading true as the AFR is spot on at WOT )
-all ground cables/connectors good

If there is anything else that's recommended to check please let me know here's a parts list for those that want more info


Graveyard performance 4 inch intake

Bnr s4 v5 Turbo

3 port EBCS Grimmespeed

3inch Obx exhaust

3 inch catless downpipe

EGR delete

Tr10 FMIC

GFB respons bov 100% VTA

JMF V1 intake manifold with port injection

Corksport exhaust manifold

44mm Tial EWG set at 18psi spring

Bosch 3.5 bar

AEM 340lph e85 safe intank fuel pump

Auto tech hpfp internals

K-motor fuel pressure regulator base 45psi with 6AN return line

X4 ID 1050 injectors

Split second controller

Overspeed fuel injector seals

Damond stage 3 dual catch can

Damond pcv plate

Jbr mounts all around



Built Motor- 100k miles

Manly H-beam rods

Mahle 4032 pistons (88mm)

King racing rod bearings

CLEVITE main bearings

BSD delete

ARP head studs

Oem head gasket

BC0400 springs (86lbs) & titanium retainers

 

[Enki]

I'm guessing that the intake is new and doesn't have an airflow straightener.
I'm also guessing this didnt happen on the last intake.

If both of the above are true, get a Treadstone honeycomb airflow straightener.

 

[jesus]

I'm guessing that the intake is new and doesn't have an airflow straightener.
I'm also guessing this didnt happen on the last intake.

If both of the above are true, get a Treadstone honeycomb airflow straightener.

The intake dose not have a straightener but has been on the car now for about 6 months and was tuned with it and ran fine, only things I've recently added is a external FPR and the jmf port injection manifold which I've gotten a touch up tune for

 

[Enki]

I don't care who told you but "You don't need a straightener" is only true for a short time. I bet if you rotate your filter the trims will change.
I once talked to a guy that had a Graveyard intake and he asked for my help with random idle issues; he said the idle would go to shit with the AC on, and while on a call I could hear the wind on his phone and the idle from his car fucking up; the wind blowing over his engine bay or the AC kicking on the fan was enough to disrupt airflow.

He got a Treadstone honeycomb straightener and later reported that it never ran so smoothly.

If you get one, when you go to install it, just lightly crush the outside just enough that it will take effort to push it into the intake; it doesn't need to be glued or welded in or anything, friction fit works just fine and the protrusion of the MAF itself will keep it from going into the turbo. If it dislodges enough for that to happen, the car will likely shut off as the flow over the MAF will be fucked up to the point where the engine will either drown or lose nearly all fueling. I've never seen or heard of this happening, though, unlike with other intakes.

 

[jesus]

I don't care who told you but "You don't need a straightener" is only true for a short time. I bet if you rotate your filter the trims will change.
I once talked to a guy that had a Graveyard intake and he asked for my help with random idle issues; he said the idle would go to shit with the AC on, and while on a call I could hear the wind on his phone and the idle from his car fucking up; the wind blowing over his engine bay or the AC kicking on the fan was enough to disrupt airflow.

He got a Treadstone honeycomb straightener and later reported that it never ran so smoothly.

If you get one, when you go to install it, just lightly crush the outside just enough that it will take effort to push it into the intake; it doesn't need to be glued or welded in or anything, friction fit works just fine and the protrusion of the MAF itself will keep it from going into the turbo. If it dislodges enough for that to happen, the car will likely shut off as the flow over the MAF will be fucked up to the point where the engine will either drown or lose nearly all fueling. I've never seen or heard of this happening, though, unlike with other intakes.

ill order one up and see if the issue proceeds to happen or goes away... will be back once installed and ran

 

[Enki]

Remember what I said about installing it; it doesn't matter if the edges are a little fucked up as long as the majority (including the center) are in good shape. Just crush the areas on the outside that prevent installation, and let the friction from pushing it in act as the mount. This is what mine looks like and it works perfectly:

 

[jesus]

Update, installed the MAF straightener and re flashed the tune took it on a 30 mile drive and same thing at idle. Though I will say it is a lot more consistent AFR wise. My next step is probably going to be testing again for air leaks and or other recommendations. Maybe the motor might just be losing its compression.

 

[Enki]

The trim difference between a hot idle and cold idle is significant; always tune the car for a hot idle, as that's going to be where it lives most of the time (and you shouldn't be doing short trips only in a DI car; they need to get HOT to keep the oil alive as long as possible).

You're lean at idle because the trims are maxed out on the STFT side; 25% + another 10% for long term. Probably needs a calibration. A quick test you can do is to touch the gas lightly until the idle comes up to 1k ish and see if it trims out better there; otherwise I'd get the tune touched up on the idle calibration side. Also as a quick note, 4" intakes are not generally known for their superior idle quality...This is why I'd limit the car to a 3.5" intake below a 650 HP goal or so.

Who's the tuner?

 

[jesus]

The trim difference between a hot idle and cold idle is significant; always tune the car for a hot idle, as that's going to be where it lives most of the time (and you shouldn't be doing short trips only in a DI car; they need to get HOT to keep the oil alive as long as possible).

You're lean at idle because the trims are maxed out on the STFT side; 25% + another 10% for long term. Probably needs a calibration. A quick test you can do is to touch the gas lightly until the idle comes up to 1k ish and see if it trims out better there; otherwise I'd get the tune touched up on the idle calibration side. Also as a quick note, 4" intakes are not generally known for their superior idle quality...This is why I'd limit the car to a 3.5" intake below a 650 HP goal or so.

Who's the tuner?

I sent hot idle logs out after driving and doing pulls I recently got a revisions with more fuel at idle and slightly higher rpm and it still pegs its self in the 15 range and stft locked at 24
Tuner is Justin freektune

 

[Enki]

Let him iterate, might need another revision or two to actually level out.

 

[jesus]

So if i do lightly tap the peddle the AFR and STFT do change back to within 14.0-15.2 and 12-16% . I can grab a quick log of it. Justin sent me a update map with more fuel at idle and it still leans out and locks at 16 AFR. What i don't understand is that randomly it will have moments where the AFR is spot on at idle wither there is air movement in the bay or not then after a couple stop lights back to lean and pegged trims. could this be ECU related or a o2 sensor?

 

[Enki]

Honestly it still could just be trims.

Edit: Your tuner is working on it, just do what he says.

 

[Crazycanadian]

This is a common trend with tuning. If you're tuner isn't telling you there's a problem.. Keep following what they are asking you to do. Some times is takes a few revisions to get things into a decent place. Unless your tuner is telling there is something wrong that needs to be diagnosed, sit back and let him do his work. If you are making changes while tuning is taking place, then you are introducing variables that can cause more problems.