Question for all you f/ic turbo users.

[SuperSonic]

Ok, so i finally got the apx turbo put on. It all works and what not, and i just got it tuned. My a/f is good at 11.3-11.8 across the board till 7 k it goes to 12.4 ( im running out of fuel i know and tuner said for short bursts i be fine but dont do a 5th gear highway pull cause it will lean out with the boost holding that high at 8k rpm). I'll post sheets later, but my real question is about the cold starts and aem f/ic. I started car up following day and let it warm up about 3 min, blip throttle and my a/f guage says 10.0. Tuner said the f/ic cant tune for cold start so car has to fully warm up to operating temp. So later that day i start the car, let it warm up to the coolant is normal, blip it and it dies. Start the car and give it 30 seconds and its fine and running smooth. I havent started it since this last weekend, so cant say if it does it again. But how do cold starts work with the fic. Did it stall cause it thought it was still in cold start? Then i cranked it and it recognized it wasnt in cold start? Should i wait longer on the initial start. And is this normal. Thanks guys

 

[SuperSonic]

Yeah, I let it prime longer and it starts up good, just if I literally blip throttle it dies on a cold start. Once the car is warmed up or after it dies the first time it is smooth. So I don't know if the car still thinks its in cold start or what not. It literally went from 14.9 a/f to 10 on the small blip of gas then died. Started it up 20 sec later it was good. Thoughts?

 

[NetViper]

My understanding is the fic doesn't effect cold start, only boost. The Oem ecu handles the cold start.

Sounds like something else is wrong to me.

 

[kookoo4nsx]

Ok, here's the deal. Either you have something wired wrong with you FIC or you have a bad FIC. Are you throwing any CEL's? Did you wire it with a boonslang harness?

I can tell you this, my car runs 100% stock when it comes to cold starts. Once day I came to a stop sign in town and my car just stalled. I restarted and it ran like crap for about 2-3 seconds and then ran fine the rest of the way home.

Here is the key why I think you have a bad map sensor on your FIC. The next day when I started my car, it ran horribly. The AFR was 14-15 at idle and then in a few seconds it dropped to 10 and the car would not rev up.

Long story short, I sent the box back to AEM. They said the internal MAP sensor was bad. There are at least 2 other members here that have had a bad AEM box and one member had 2 bad FIC's. AEM ended up replacing my FIC board at no charge.

Call AEM technical line, tell them what your issue is. I think based on your AFR going to 10 you have the same problem. AEM can test your box and get if back to you in a few days. It is a waste of time to look elsewhere. While your car is down for a few days, upgrade that fuel pump.

 

[DDozier]

What size injectors did you put in with your kit?

What other changes were made to the fuel system?

Where exactly did you install the wideband O2 and is that the sensor you are basing your WOT numbers off of or the dyno's wideband measured after cats?

The F/IC can and should start just like the OEM ECU, the wait for prime thing is only for the AEM ECU and will make no difference with a F/IC. Your OEM ECU is running the show durring startup the F/IC is only compensating for the change in injector size at that point.

You will need a scan tool along with your wideband to get the F/IC setup correctly , It sounds to me like your long term trims at normal operating temps are probably running at -15 to -20% this will make your cold start extreamly rich as the car does not trim for a few minutes after start up while everything starts to get up to temp. If you have really large injectors this is harder to correct but if you have 440, 550, even 750cc you should be able to dial this in. You may also have an issue with the Primary O2's not heating up quickly enough but you need to know what the trims are doing to figure this out.

You should be getting a fuel pump ASAP, you should short shift before 7K rpm untill you do.

Dave

 

[PATCHEZ]

I run the ap-x kit and my car did run like crap until warm. When I brought the car to Shad he found my fi-c wasnt loaded with the right firmware for the NSX. So he reflashed it. You may want to check that first.

 

[DDozier]

I run the ap-x kit and my car did run like crap until warm. When I brought the car to Shad he found my fi-c wasnt loaded with the right firmware for the NSX. So he reflashed it. You may want to check that first.

Very good point, this will make a huge difference if you are not running the correct firmware.

Info about the correct F/IC and firmware can be found in this link:
http://forum.aempower.com/forum/index.php/topic,21283.0.html

Dave

 

[RYU]

+1 on needing more info about your fueling components (injectors size, fuel pump, stock fuel pressure?)

 

[Valhalla]

He is running the Bosch 550 injectors but stock fuel pump. Don't know if he has upped the pressure though and I'm assuming form these numbers he hasn't.

 

[RYU]

Dave would have more hands-on experience here but using the stock fuel pump on anything more than 350hp would give me gray hairs.

 

[Valhalla]

And really skinny AFR's.

 

[E-Nough Logic]

my car with the BBSC and fic ran 100% as stock, with no exaggeration. It was transparent. It was awesome.

when I switched to the turbo setup, there was some rough running until the car had about 2 minutes of run time, then it smoothed out and ran like stock. After i switched to the aem ems the car is again like stock, with exception of slightly longer cranking before firing.

Just leave the key in accessory for 3 seconds and it will fire up immediately when you go to start. The AEM ECU won't even attempt to fire the engine for the first couple seconds it is powered up.

 

[SuperSonic]

The injectors are just the 440's. The fuel pump i couldnt say to be honest. The previous owner had all kinds of top of the line upgrades done, upgraded the s/c with every part possible, ect ect. So there is a chance the fuel pump may be aftermarket as from the dyno ill post later today, its in the 11 range till 7.5k then its at 12.4 by redline.

How can i know if the firmware is up to date? Can i install that or the tuner has to do a new tune? And the aem could be bad? Would it help to make a you tube video? To show what im saying? Like it starts up fine, idles good, even cold start good, but during cold start its like it cant even touch throttle and it goes rich. I took it to shawn church, whom has a very good rep so i wouldnt want to say he screwed up.

Oh yeah, so
440 cc bosch
Possibly upgraded fuel pump but i did remove resistor
Aem wide band in flowmaster tip of muffler 12 inches from turbo
Its got a boomslang harness
Car has 44k miles, so dont think o2 are bad

 

[SuperSonic]

Ok, here is the dyno sheets to see if this helps at all and to get some feed back. Scanner was broke, so had to take pics of my sheets, sorry for not having HD pics :/ The red is with the turbo xs manual boost controler turned down as low as it can and it is at about 7-8 psi. The blue line is with out a boost controler, it was only at around 3 psi.

and here is the video's i put on you tube to show you guys. Its like literally if i put the ebrake down it signals to exit cold start or something cause it almost dies, then literally 5 seconds later it is perfect.....
http://youtu.be/WDWn0aMm7Ys
http://youtu.be/LEkpcWZyMpw

 

[SuperSonic]

Just leave the key in accessory for 3 seconds and it will fire up immediately when you go to start. The AEM ECU won't even attempt to fire the engine for the first couple seconds it is powered up.

as far as starts, it is fine. Once it did barely start, but i started it this morning to take the vid you see in the above post, and it started just fine. My only concern is why it bogs if you press the gas at all. As for the fuel pump Dave, my question is wouldn't it start to show much earlier in the dyno sheets? I mean I have a vid on you tube where the car ran 460 whp on a run and I told them to get it lower lol. At 460 it was starting to go lean obviously, but a stock pump, wouldn't that start to loose fuel around 400 hp? I know the 440 injectors must be at their max limit at 460 hp, and that's why i told them to get it into the 420-430 hp. I know the 440's were maxed, but if the fuel pump was in fact stock, wouldn't it go way leaner at even 410 hp. Just my thoughts. Like I said, a previous owner put some serious $$$ into the car, the full comptech kit with air box and headers, had brembos and who knows what else so he may have upgraded the fuel pump as well for all i know. The fuel pump is a maybe, but i do know I put in 440 injectors and their max is where they are at now.

 

[peiserg]

Just leave the key in accessory for 3 seconds and it will fire up immediately when you go to start. The AEM ECU won't even attempt to fire the engine for the first couple seconds it is powered up.

that has not effect.

 

[SuperSonic]

Ok, started it again. It literally bogged until it physically was at the normal op temp and the rpm droped to 850. It was at 950 rpm, it bogged so i waited, it droped to 850 then it was perfectly fine. Thought? Is this what yours did brian?

 

[RYU]

Ok, started it again. It literally bogged until it physically was at the normal op temp and the rpm droped to 850. It was at 950 rpm, it bogged so i waited, it droped to 850 then it was perfectly fine. Thought? Is this what yours did brian?

Sorry if I missed this... but what is your AFR reading when it's bogging like that? Is it below, say.. 10.5?

My thought is.. if you're using 550s and the stock ECU takes control of all cold start functions then your engine is getting fed too much gas when cold. Based on what folks are saying here the FIC take control of injector pulses until it's warm. My car, with the stock injectors already run rich during cold warmup. Which explains my thought process...

 

[SuperSonic]

Sorry if I missed this... but what is your AFR reading when it's bogging like that? Is it below, say.. 10.5?

My thought is.. if you're using 550s and the stock ECU takes control of all cold start functions then your engine is getting fed too much gas when cold. Based on what folks are saying here the FIC take control of injector pulses until it's warm. My car, with the stock injectors already run rich during cold warmup. Which explains my thought process...

Ryu, i am running bosch 440 injectors and yes, only during warm up if you bliped the gas my a/f said 10.0-10.5

This would make a lot of sense. My tuner did say he couldnt control cold start and my 440 cc would pour a lot more gas if the ecu did a stock set up, plus i removed the restrictor for the fuel pump AND on top of that the day it was tuned i bliped the gas and it almost died so the tuner said he would richen and fix the lower rpm. It didnt hick up once after that on drive home.

 

[DDozier]

Ryu, i am running bosch 440 injectors and yes, only during warm up if you bliped the gas my a/f said 10.0-10.5

This would make a lot of sense. My tuner did say he couldnt control cold start and my 440 cc would pour a lot more gas if the ecu did a stock set up, plus i removed the restrictor for the fuel pump AND on top of that the day it was tuned i bliped the gas and it almost died so the tuner said he would richen and fix the lower rpm. It didnt hick up once after that on drive home.

OK, first things first you have two issues going on and they are not related to each other.

First issue is going lean on top, You are running out of fuel for one of two reasons, you are out of pump or you are out of injector. I do not think with 440cc injectors you are going to be able to make 430whp at stock fuel pressures. So without a boost-a-pump or larger injectors you may have to pull boost and get your power level down around 400whp. I have seen stock fuel pumps support 350whp and I have seen them only get to 325whp it all depends on age and condition, I would guess the pump has been replaced already but with what? and what is the condition now? either way you are still running out of fuel and I am guessing it is the injectors, 550cc would be a better size for your power goals.

Second issue is cold start, You need to verify the z110.hex firmware has been loaded on the FIC. I put in a link to AEM's software above but here it is again: http://forum.aempower.com/forum/index.php/topic,21283.0.html . Instructions on how to check and flash the firmware are here: http://forum.aempower.com/forum/index.php/topic,23723.0.html if you do not feel like you understand this process completely do not attempt to flash the firmware yourself have your tuner do it. You can brick your F/IC if you do not do the flash correctly.

Once you know the correct fueling firmware z110.hex is in the FIC if the problem is still there you need an OBDii scan tool to resolve this issue, without it you are not going to get through this process. You have to have the live data from the OEM ECU to look at long and short term fuel trims. With this data if all other mechanical issues are resolved you can fix this cold start issue. I am betting the z110.hex is not loaded. This is special firmware writen just for the NSX to deal with our cars unique startup fueling strategy and will not be in the FIC out of the box it has to be installed by the end user/tuner.

Double check the firmware, get a scan tool and let us know the results.

Dave

 

[SuperSonic]

Thanks dave. Tomorrow im just going to drive back out to the tuners and have him update it. I dont know if it will mess up any tune i have so far so best let them do it. The car can still be driven till then right, or does that adjust anything and everything?

 

[DDozier]

Thanks dave. Tomorrow im just going to drive back out to the tuners and have him update it. I dont know if it will mess up any tune i have so far so best let them do it. The car can still be driven till then right, or does that adjust anything and everything?

Should be OK just stay out of boost untill the final tune is done and the Tuner says you are good to go, I think but am not 100% sure but I think the "SPECIAL" firmware is only dealing with the start issues unique to the OEM NSX ECU. How it has been described to me is that the car starts in batch fire mode and stays that way during high idle and most likely is tied to ECT or at least on some sort of timer as to when it goes sequencial. Devon at AEM described it to me once when we were talking at SEMA a few years back. My guess is they changed the firmware after cold start to only look at one of the injectors as a source and then batch fire all the injectors. This way the F/IC would not have to calculate all the injectors at a single time. The F/IC may not have enough processor to calculate and fire all 6 injectors at once. I am not sure though, just a guess on my part. Once the OEM ECU goes sequencial the F/IC should be operating as it was originally designed.

If you do not have a OBDII scanner in your tool box you should get one, the F/IC can be a bit of a handfull to iron out all the little issues, having the data to show the tuner on follow up tunes is very helpfull. If you are obsessive like me about the cars manners you will want one. The fine tuning of the tune while in cruise goes along way to making the car and the F/IC happy with each other.

Make sure he backs up the current tune prior to the Flash, the calibration process to setup the F/IC is saved in the tune so that should not change but it would be a good idea to re-run the setup wizzard for calibration of RPM and TPS.

Good Luck and let us know how it worked out.

Dave

 

[SuperSonic]

Well so far so good. He was using firmware z107, the standard firmware. I havent yet truly done a cold start, but after the update i did notice it started fastet and the idle was smoother. It sat for 30 min after the flash, and after i started it i bliped the gas and no bog, so far. I'll know for sure after i start it sat morning. Fingers crossed, so far so good. Thanks for all the help guys.

 

[DDozier]

Well so far so good. He was using firmware z107, the standard firmware. I havent yet truly done a cold start, but after the update i did notice it started fastet and the idle was smoother. It sat for 30 min after the flash, and after i started it i bliped the gas and no bog, so far. I'll know for sure after i start it sat morning. Fingers crossed, so far so good. Thanks for all the help guys.

Good news, now one other thing to check, did you have your F/IC harness made with the OEM Primary O2's wired into the F/IC with the resistors, or are the O2's not connected?

You can check this by looking at the harness itself. If the O2's are wired in there should be two resistors wired in series with the F/IC wires. They will most likely be covered in heat shrink tubing so you will have to look close to see them. If they are there, you may want to remove them from the harness and diconnect the F/IC's O2 modifier wires. Then reconnect the patch harness so the O2's signal is straght through to the OEM ECU with no connection to the F/IC.

Your fuel trims could have issues if the F/IC is connected to the OEM O2's. We do not need to use the O2 offset feature in the F/IC so making these connections is of no value and can cause drivability issues.

What are your plans for the lean condition at the top of your pull?

Dave

 

[RYU]

thanks for sharing your knowledge Dave. We're learning a ton from this thread.

Please PM me if you're in LA anytime this year :smile: