Hello, I wanted to get some other opinions on this, as I am pretty inexperienced dealing with actually going in and making adjustments. This is my first car I’ve been able to do it on.

anyways, I’ll try to make this as clear as I can. On a 80 degree day or so. As my IAT creep up, my idle goes very lean and the car sounds like crap. I can freely rev the engine and it clears up. Seems to be only at idle. Driving it’s fine, but as my IAT get up past about 120-125. It goes lean(16.16.5). From 125-130 it’s very lean(16.5-17) and north of 130 it’s around 17.17.5.

warming up isn’t an issue, but it’s always real noticeable once it’s say a few mins heat soaking and I restart it. Once the injectors have heat soaked, there still measuring about 14ohms (RC750) and the fuel pump maintains a solid 43-45psi at idle.

now what I can do, is go into the Neptune software and I can go to the IAT corrections and take the low fuel 121 column and it was at 0, I set it at 8 trim correction, and the 158 column I set at 12. It was at -.05.

Making those changes, got my idle Afr to 14.7-15. I thought this was a bandaid fix (it still might be) for maybe an injector building high resistance when it’s getting hot, having to force a little more fuel in via the corrections. But at least on the resistance side, they are “ok”

I was just playing around with this, and I only made those adjustments and I wrote down the originals. Something just don’t seem right, or is it an ok practice that I just haven’t had to deal with yet.

the car is running open loop, as even with the wideband option clicked the car leans out and dies in closed loop and holds a 0% fuel trim. I know there was a few other things to look at on that as well, but I’d almost think running in closed loop would help itself correct the idle, but I’ve got more Learning to do before I get there.

any help and advise is appreciated. Thanks!

 

Since you're in an open loop, have you made any adjustments in the VE Fuel Enrichment Maps, especially at idle?

Also, is the post start set at "ZERO"?

 

the box is unchecked to use VE maps, so from my understanding I’m only using the primary fuel maps to control everything. I can adjust up at my 4 idle cells, and I can get it back on track that way. But when the temps get a little cooler or at a cruise then stop light id be idling at around 11.5-12afr. So I just put it back where it was and started playing with the IAT low load corrections. And I don’t remember seeing anything about post start, I’ll jump on the tune and see.

 

I’ll also add, now that I’ve got my tunerview app set up, I’ve really been able to pay attention. And I’m not too certain it’s a heat soak issue on any of the components. It seems as anytime the IATs are high, it does it. Not so much after a restart, but after sitting a few off after a drive I’m guessing the IAT was just warming up a lot since airflow stopped.

have you guys ever seen one where the correction had to go so extreme to get it to idle right? I mean I could see 1-2 being acceptable. But I went from .05 to like 12. That just seems very, well, not right.

and pardon my ignorance on this. I’m trying to get a grasp on it.

 

Post start...is under Parameters, Fuel/Ignition Corrections, Injector Calibration....bottom of menu

As of right now, I'm just able to see the menus and able to adjust some values, but haven't connected directly to my ECU just yet. Should be sometime this upcoming week. I'm on a Neptune tune but via burned chip. I just recently ordered "another" RTP Demon2 and need to adjust some things. It's currently running lean like hell on heavy load.

 

Ok I will play around with that one later, and I jumped onto this, and apparently VE table box is checked above 126ect.

now going to modify the post start trim, will effect the trim across all Temp ranges no? I have a feeling on a cooler day (where everything now is just fine) it will make it go very rich.

I’ve been reading many places here lately, and read into the Neptune help section as well as some forums. So so far the issue I have don’t make sense. I mean as air gets hotter, it expands. I’d imagine if I’m having a fuel issue it would be going rich, not lean. I could see as the air gets dense going lean as now air has slowed down and of course is more dense so you’ll need more fuel to accommodate that. I mean that’s how the default corrections I have are set up.

I mean technically with me setting those IAT corrections, the issue I was having has corrected. I just feel that was more of a bandaid for another Issue that just don’t have set up right.

 

Yeah, the IAT/fuel corrections is a bit tricky. For instance, I cranked the car this morning around 9am and it caught like the 2nd try. When I let it park on the street curb for a few hours, I was able to crank it on the first try. Usually, when it's colder outside, I will have to let the car warm up first before driving. If not, it bogs when I press the gas until like 3 blocks away. I'm sure the previous tuner wasn't thorough with the tune. **** like that pisses me off. You pay someone money to get your car right and they halfass it. Some people have no pride in their work.

 

Yeah that’s understandable. I’m pretty confident in the guy who tuned my car at least. The car ran very well up until it got warm outside and my intake temp starting going up. Now I’m dealing with the lean and crappy idle. Ah, oh well. I guess enough reading and tinkering I’ll get something figured out.

NV are you trying to do all your tuning yourself?

 

I'm going to attempt to. I have an extra P28 ECU that I will be installing the Demon 2 on there. My plan is to see how close I can get the car to running right. I understand a good bit of what the options/parameters do. If it goes haywire, I can always put back the "current' ECU and wait until I take my car to the dyno.

 

I gotcha. I’m using the demon 1 in a jdm ecu. So far everything has worked well within the software. I had mine tuned, and have just been making mild changes to the fuel table in the vaccum portion to attempt to smooth out some of the take offs as I had a lean spot that would always bog on take off from a light. Well good luck to ya.

 

Thanks...I'm not intimidated by it, just curious on what some of the stuff actually does when you adjust numbers here and there. Street tuning is going to be somewhat of a challenge but that's what the datalogger is for. My wife likely won't sit in the passenger seat to look at the graphs while I'm testing it out. LOL She's not a car person.

 

I get that. If I decide to try anything myself I’ll be in the same boat lol

 

The Demon2 board showed up yesterday and I was able to get everything installed onto the ECU. Connected the ECU to my laptop and everything seems fine However...I installed the 28-pin connectors backwards and I attempted to swap it around (the Demon board seems visibly higher than it should). Ended up bending 2 of the prongs. Tried to bend them back and broke one of them. SMH...
Had to order replacements so it's on hold until it shows up. I hate working on cars sometimes. LOL

 

Nathan.. What's your engine setup? Also, can you scrrenshot your IAT and ECT corrections?

NV.. Same for your setup, what's your engine setup again? I have over 70 of my own tune files and I may be able to send ya one to get you started!

 

The low load 121 and 158 column I bumped up to like 6, then 10. And that rough my the Idle back to 14.7 with the IAT at around 140.

b18c1
piston and rods, stock sleeves
ported head from NA build, ported. Now with GSR cams
garrett TA3405 (t3/t4 JB .57 stage3 wheel)
rc750
walbro 255
aeromotive FPR
jdm p72 with demon
i have recently switched to a ramhorn from a log manifold, but that’s another story for another day lol

 

You running pump 93? It seems pretty strange to have any fuel subtracted unless the IAT is >140, and I myself have never subtracted any on low load, regardless of IAT. I'd probably wonder why IAT is getting that high anyways but, like your manifold switch, that's another story. Lol! Anywho.. On startup, Neptune will look at IAT and ECT and adjust idle accordingly until you reach operating temp: usually what you set your cold/hot boost threshold at. Think i put my threshold at 120 ECT. Some consider operating temp as when the radiator fan kicks on but, well, this can vary wildly as well. Lol! Just pick a happy medium.. I warm it up until my fan kicks on: 185 ECT.

Another anywho.. Neptune also reads between columns. Let's say, column 1 is 120 and the next column is 158. Now, your temp is 140. Neptune will interpolate (?) Between those columns for proper AFR. I put my targets a bit closer together after a similar ordeal, example: ECT 0 | 60 | 100 | so on.. This helped a lot as well. I don't have a coolant line to my IACV either so, I am usually fussing more than a couple times during the year to set her straight.. Usually when temps get to be 30 and below, then again 70 and above.

 

the IAT rose to that level when it was sorta warm outside, around 77 if I remember right. And it was sitting in a drive though running for around 1/2 hour. Under most normal traffic lights it doesn’t get that high. The other scenerio is after I drive it, park it, let it heat soak for 10-20 Mins, get back in and the IAT temp is high from sitting when hot. It will idle real lean, then as soon as I start driving and come up to another stop sign for instance, iat are usually back down around 100 and it idles fine.

it’s not warm today, so my IAT aren’t going above 100 even after me sitting. My tuner is busy, so I’m trying to mess around with this car today. As when I put my new manifold on, under boost it goes very lean after vtec. So I’m learning, trying to get some fuel added up top, I’ve considered pulling about .5 degree across the high cam map to be on the safe side, but I wasn’t sure how much me changing the manifold would effect the ignition timing.

i know getting the under boost afrs back down to around 11-11.5. I’ve never actually went in and made important changes, and I’m terrified of screwing something up, so I’m going heavy on the fuel and not advancing any ignition. If the guy I use stays busy, I’ll break down and really start pulling plugs after I do pulls. The way I had it in my head was let’s say do a pull to 5000. Cut the car off and pull plugs. Adjust timing if needed via the mark on the ground strap, sand the plug then do a pull to 6k and repeat that to make sure I’m not too advanced.

i was running the fuel very heavy under boost, like 10.7-8. And I noticed my boost creeping. Now that it’s back up a little bit, it seemed to calm down a smidge. Ah idk, I’ve read quite a bit. And I’m to the point I need someone to teach me hands on or just go at it myself and make small changes so I don’t dick it up too bad.

 

Heat soak is totally normal.. That will *usually* settle back down once you get moving again. Most instances, you can help it along with a couple WOT pulls. This is also if you have a decent intercooler. Lol! Timing is fun. On the street, it helps if you have a det can. Google that, SUPER cheap and easy to make. On the dyno, you'll really get to see a little goes a long way. I gained like 10whp and 8tq with only .25 deg advance up top, but I was also previously pretty conservative with timing.. Think I was around 13.25 or so @6500 rpm. 25psi, 11.9-12.2 AFR WOT after 2.5 deg advance and i lost clutch. Lol! Timing... A little goes a long way!! Try out .25 to .5 at first to see how it feels for ya, drop the AFR to 11.5 and keep your ignition timing to about 12-13 degrees up top, she will scream!
Edit: Actual timing, not table timing.. Don't set your table timing to 13.. You'll blow something for sure. Lol! Nah.. Just remember, the table timing in Neptune DOES NOT reflect compensations.. When you view a data log, add table and actual timing to your graph and you'll learn a lot.

 

Thank you for the advice. I think near redline I’m also trying at about 15 at 20 psi. I may attempt to get the pwm duty cycle mapped out, so I can apply it to gears. But I think I need to lean it out in boost a little more. I’m still getting quite a bit of creep, especially near redline.

 

You trying the boost by gear now? As in, running it now? I stopped using it due to all kinds of gremlins trying to dial it in. I'm not THAT confident in my tuning abilities. Lol! I reverted back to my Hallman MBC and haven't looked back. Once I switched off BBG, I've not seen a single boost issue.

 

yeah well I was trying too. But I can’t even get my boost levels under control (again). I’m running direct wastegate. 8psi spring. Until vtec it’s 9psi, as soon as vtec it heavily creeps up until 20psi redline. It’s still very rich, I’ve reduced that down twice now, at 5% in those upper columns. And it’s like it didn’t change anything at all. I’m getting aggravated. I think I need to give it a break for the day.

 

That would be great!!
D16y8
75.5mm bore, Vitara pistons, SF no-notch rods
Turbonetics 5057 turbo
RYFAB ram horn manifold, 3" DP, dump tube
Edelbrock PerformerX intake manifold
TIAL 38mm wastegate
1000cc injectors, AEM 340lph pump, Aeromotive FPR
strictly E85

Yesterday, I plugged up the ECU to my laptop and noticed the "RED" light stayed on. Tested the ECU out (with the current chip) in the car and it wouldn't start at all Checked the soldering and fixed some joints. Reconnected the laptop to ECU and no more red light. Will likely test in the car again soon.

 

Have your injector dead times offhand?

 

TPS tip-in and cranking trim are both -76