Apexi' NEO tuning/general tuning advice

[mattmk3]

Reset ECU while HOT, figuring it needed to be warmed up to use the o2 to adjust idle, but it did not matter, Idle is still OVER 18a/f. Went out for a drive with fuel pressure at 30 which i believe is too low, it was because i backed it off for the 550cc injectors with no lex maf, but then:

-Came back quick, readjusted that. Will STILL not idle at 15a/f like it did with the stock afm.

-Adjusted fuel pressure to 38psi no vacuum. No change, still over 18a/f off the scale.

-Adjusted the Lex afm screw all the way closed. Slight change in idle a/f.

-At cruise, it sits at 17-17.9 a/f
-At a slight incline, it sits 16.2 a/f
-I did not want to boost it but if i stepped into it a bit, it would gradually go through 15-12 a/f but i never actually got into good boost, too nervous, i feel like it's running LEAN and i'm frying things.

Or maybe that's normal and i'm just used to 550's with no lex afm? Is what i'm seeing normal? It feels good, but that's feel... AEM wideband is in the red most of the time and it just seems bad...

I'm getting super frustrated with this and I'm going to snap. What the hell am I doing wrong?

[cre]

I don't have time to go over this tonight, but here's a tip. Smell the exhaust. Unburnt fuel causes a lean reading on a wideband. You are fighting with this more than someone with experience but no more than any other novice, especially when they've made too many changes at the same time. Set the fuel pressure to stock. Set the NEO to zero across the board. Look to see how far rich or low you are across the board and make a mainscale adjustment to account for that. Then trim each section as needed on an individual basis. The ECU doesn't learn how the engine is running from one single session and I believe it continually adjusts to changes as well. After the first couple drives it should be pretty well set though. Resetting the ECU when the car is cold or hot isn't going to do much it's looking at averages from multiple samples.

DON'T PANIC A lean idle isn't an engine killer unless other things are wrong (no EGR to cool things down, heavily advance ignition, etc.).

Is the stock O2 sensor still installed? Or is the AEM providing the ECU with a narrowband signal? If the AEM is providing the signal make sure it's properly scaled and the wiring is rock solid... Doesn't take much to throw the signal off enough to cause the ECU to think the AFR is WAY off and perpetually over correct.

[mattmk3]

Originally Posted by cre

I don't have time to go over this tonight, but here's a tip. Smell the exhaust. Unburnt fuel causes a lean reading on a wideband. You are fighting with this more than someone with experience but no more than any other novice, especially when they've made too many changes at the same time. Set the fuel pressure to stock. Set the NEO to zero across the board. Look to see how far rich or low you are across the board and make a mainscale adjustment to account for that. Then trim each section as needed on an individual basis. The ECU doesn't learn how the engine is running from one single session and I believe it continually adjusts to changes as well. After the first couple drives it should be pretty well set though. Resetting the ECU when the car is cold or hot isn't going to do much it's looking at averages from multiple samples.

DON'T PANIC A lean idle isn't an engine killer unless other things are wrong (no EGR to cool things down, heavily advance ignition, etc.).

Is the stock O2 sensor still installed? Or is the AEM providing the ECU with a narrowband signal? If the AEM is providing the signal make sure it's properly scaled and the wiring is rock solid... Doesn't take much to throw the signal off enough to cause the ECU to think the AFR is WAY off and perpetually over correct.

Just noticed an error I made, I said RICH when it should have said lean frying things but i think you picked up on that.

I've been driving it around, it feels awesome, and I've gotten into boost and it's actually a nice range of mostly around 11-11.5, dips to 10.5 at some points but in full boost, never hits 12. So it's actually boosting quite nicely. I think it may still be learning idle and cruise though because it has dropped from 17.9/off the chart to 17 and idle sometimes goes down to 15 but then climbs back up. Maybe it's trying. I think I'm just over thinking it and just being paranoid.

Utilizing stock o2. EGR IS removed. Is that a possible problem for EGT's? I've been meaning to get an egt gauge. Timing is stock spec for turbo engine.

Side note: Since it's running well under boost, i decided to crank the boost up to 17 and see how it goes. A/f's are still solid, pulls like a maniac. Gota be sitting up towards 400whp (basing off of my last dyno results and what i did to get there).

The question: Twice and only twice, when I hit it hard, preloading and then dropping into the boost, It puffed a decent cloud of greyish smoke. Not white, and not the black shit i used to spit out. Is this an indication of anything bad or just a hard working engine? Only a puff, didn't do it the whole pull.

I'm going to go through and make sure all my intercooler pipes are nice and tight and make sure everything else is good to go for 17psi. My only other issue is a oil burning issue from what I've narrowed down to be the valve stem seals.

Thanks!

[cre]

17+ AFR is leaner than you want at idle. It may creep there on occasion on a sound setup but shouldn't spend most of its time there.

Removing EGR on vehicles made after the 70's is just ignorant or motivated by vanity. It doesn't effect performance at all while at WOT (as it's off then) and it helps cool the engine after a hard run. As for the latter... MOST people couldn't give a shit what it LOOKS like under the hood. It kills me how people try every single trick they can to increase performance and at the same time nickle and dime themselves out of power based on the opinions of some guy with a mullet, '65 Mustang and 12 pack of Budweiser in his gut. Don't worry though, it's not going to kill your engine with it removed.

Are you having any issues with AFM related error codes? Are your AFR trends significantly different after cold starts vs warm? What do you mean by "preloading"? Brake boosting? The smoke is probably either running rich or oil... hard to say without seeing it myself.

[mattmk3]

Originally Posted by cre

17+ AFR is leaner than you want at idle. It may creep there on occasion on a sound setup but shouldn't spend most of its time there.

Removing EGR on vehicles made after the 70's is just ignorant or motivated by vanity. It doesn't effect performance at all while at WOT (as it's off then) and it helps cool the engine after a hard run. As for the latter... MOST people couldn't give a shit what it LOOKS like under the hood. It kills me how people try every single trick they can to increase performance and at the same time nickle and dime themselves out of power based on the opinions of some guy with a mullet, '65 Mustang and 12 pack of Budweiser in his gut. Don't worry though, it's not going to kill your engine with it removed.

Are you having any issues with AFM related error codes? Are your AFR trends significantly different after cold starts vs warm? What do you mean by "preloading"? Brake boosting? The smoke is probably either running rich or oil... hard to say without seeing it myself.

No codes or anything. This is what I mean by what the hell is my cars deal with me doing this mod. How do I go about richening up idle? it's still 17 at idle and 15-16 cruise, really light cruising 17.

Not quite brake boosting but putting a nice load on the engine then hammering on it. Just building up the boost as apposed to just waiting for the turbo, it builds more boost, quicker, so it seems that's when the most stress is on things. New note on this, I get this strange, very fast sounding, not quite a rattle, more of a grind, but not quite a grind. haha impossible to explain so I have my gopro with a remote mic and i'm going to place it in a couple spots in the engine bay and see what that noise is. It seems it happens over 17psi boost; so when i put some load then hammer on it, it spikes for a second but keeps up there and I hear it. It's only happened a couple times but if i were to take a stab at what the noise may be, I picture the compressor wheel of the turbo grinding into the housing... But the turbo is recently rebuilt and upgraded...

Cold and hot afr's actually aren't too different. Been driving it since I posted this thread, so a couple days now. Still pulls hard, feels great throughout the powerband, my turbo spools quicker a lower rpm. I just DON'T like the lean idle. I did some research, 16afr cruise isn't even bad so I'm only worried about idle at this moment.

[mattmk3]

So today randomly after pricing out some tires, it was warm, sat for about 25 mins, then i went out and shortly after, it started to have a shity idle. It has gone more lean, it's off the chart at idle now(18afr+) and it sounds like it's cammed. shaking and shit. NOW what... I didn't change anything.

[mattmk3]

Is it possible it's my fuel filter? I show pressure up to and beyond 40psi, but i'm not sure if that's a guarantee the fuel filter isn't holding it back. I'm trying to figure out why it wants to stay lean. What else could it be? I have a walbro 255 to put in but like i said, I can get probably 55psi maybe 60 and that's it. Only cranked it up to see how the 12v mod effected it.