If anything I got lots of pictures of my throttle body in pieces which I've never seen here.
AEM FIC + O2 Sensors = Stumble City??
- Thread starter Cozmo
- Start date
If anything I got lots of pictures of my throttle body in pieces which I've never seen here.
Let's see the pix of the broken part........
more info and pics posted here.. http://www.nsxprime.com/forums/showthread.php?t=140528
I'm still not sure if replacing this made any difference to my car or not. I need to reset the ECU, recalibrate the TPS on the FIC, and drive some more to see if it is better.
I'm still not sure if replacing this made any difference to my car or not. I need to reset the ECU, recalibrate the TPS on the FIC, and drive some more to see if it is better.
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Did it help?
No. :frown:
I changed all my coils the other day and it didn't make any difference at all.
I noticed that when I reset my ECU it gets worse, then slowly gets better (but not perfect) so i'm thinking maybe my fuel trims are just all out of whack. I'm fairly certain that no matter what I do with my fuel map it isn't going to fix my deceleration hesitation problem though.
One thing I did do recently is get my UEGO hooked up to the FIC so I've started capturing logs of my driving when these things happen so hopefully I can adjust my fuel map to fix this, or at least minimize it.
I also started saving money to switch to the AEM EMS, so if I don't have this running how I want by the time I have the EMS money, I'm gonna ditch the FIC. At least then when shit is bad, I can see what sensor is causing it, or tweak something to make it go away.
I noticed that when I reset my ECU it gets worse, then slowly gets better (but not perfect) so i'm thinking maybe my fuel trims are just all out of whack. I'm fairly certain that no matter what I do with my fuel map it isn't going to fix my deceleration hesitation problem though.
One thing I did do recently is get my UEGO hooked up to the FIC so I've started capturing logs of my driving when these things happen so hopefully I can adjust my fuel map to fix this, or at least minimize it.
I also started saving money to switch to the AEM EMS, so if I don't have this running how I want by the time I have the EMS money, I'm gonna ditch the FIC. At least then when shit is bad, I can see what sensor is causing it, or tweak something to make it go away.
Cozmo, What boost are you running? I have a EMS map you can have when you get the standalone. Obviously it wont be perfect due to where you live in comparison but it will get you very close.
On a side note: I have a customer car that is studdering at 5500 with FIC seems to be doing a lot of what yours is. When we get it figured out I will let you know.
On a side note: I have a customer car that is studdering at 5500 with FIC seems to be doing a lot of what yours is. When we get it figured out I will let you know.
I'm running 7.5 psi right now.
It would definitely be nice to start with a tune that has all the engine stuff already setup correctly (just need to tune the fuel and timing) rather than spending hours setting up sensors, cold start, etc.
Mine was on 9 on the tune I have in my computer. I can call my tuner and get the 7lb map for you though.
Just PM me when your ready.
Cos,
Any update on this?
Any update on this?
The more i tried to adjust it the worse it got. I did lots of driving around collecting logs and making tweaks to my fuel map and it didn't really help.
I'm not messing with the FIC any more. My EMS should be here in a couple weeks. It is being built by AEM right now.
I just got off the phone with the shop i'm going to have tune it.
They do lots of high power hondas. I told the guy I was tired of the FIC and how it drives and he described the exact same problem I'm having with mine and says he sees it a lot. Hooray, I'm not crazy. :wink:
I'm not messing with the FIC any more. My EMS should be here in a couple weeks. It is being built by AEM right now.
I just got off the phone with the shop i'm going to have tune it.
They do lots of high power hondas. I told the guy I was tired of the FIC and how it drives and he described the exact same problem I'm having with mine and says he sees it a lot. Hooray, I'm not crazy. :wink:
Cosmo, wasn't the FIC suppose to be used with OBDII cars? I know that it could be made to work with OBDI, but I thought that the AEM EMS was recommended for that?
That is correct. You *can* use the FIC on OBD1, but you can't monitor fuel trims, which means you have to guess, and fight against the stock ECU to get what you want. I only did it originally to save money, which was a stupid idea. It is cheaper becuase the hardware itself costs less and can be tuned faster than setting up the full EMS. HOWEVER that simplicity is also the downfall as you basically have control over nothing but fuel and timing.
My "very light throttle hesitation" is the car running really lean, and no adjusting of the FIC can make it stop. I open up the tune file that SOURCENSX sent me for the EMS and lookie there, they have a selling that says "Idle off if TP over ___ %" so you can actually adjust that exact thing I seem to be experiencing. If only the FIC had more options it may have saved me about $2000.
It doesn't require anything special to work on an OBD1 nsx, it plugs in just the same.
I'm not saying the FIC sucks. Clearly there are lots of people here using it without issues, but it doesn't work for me.
Hey Cozmo, do you have a wideband in the car, hooked to the FIC?
Did you buy a plug and play harness or splice you FIC in?
When you reset your ECU does the car seem to work from lean to rich or rich to lean before it finds its happy place?
What injectors and other fuel mods do you have?
If you want help with the FIC untill your AEM ECU shows let me know and I will try to help. If there are no mechanical issues and it is just your map then this should be able to be sorted with the use of a good wideband and a little time.
Dave
Did you buy a plug and play harness or splice you FIC in?
When you reset your ECU does the car seem to work from lean to rich or rich to lean before it finds its happy place?
What injectors and other fuel mods do you have?
If you want help with the FIC untill your AEM ECU shows let me know and I will try to help. If there are no mechanical issues and it is just your map then this should be able to be sorted with the use of a good wideband and a little time.
Dave
Yes, I have a UEGO wired to the FIC using the boomslang harness.
I have 440 bosch injectors, a walbro 255 pump, and an AEM FPR. I think my fuel pressure is a bit higher than stock too.
It pretty much does exactly what you mention where it doesn't seem to like where the fuel is and often takes a second to find a good spot. It seems to get better as the fuel trims get set over time but if I reset the ECU it is ugly again for a couple days.
I've tried logging my driving and adjusting my fuel map. I've also tried unplugging the O2 sensors and doing the same thing.
The low end of my fuel map is -37.5%. The auto fuel map calculator in the FIC software says it should be -45.3. I suppose it could be that the fuel trim has the whole map turned down a bunch due to it sounding like it must be way rich.
I suppose I could change it to -45 and reset the ECU and see if it is even close to right. Although that's what it was on my original tune and it still had the same problems then.
According to this calculator a 4psi increase in fuel pressure on my injectors would result in a 5% increase in fuel. I need to check my fuel pressure guage and see what it reads at idle vs. the stock spec (46-53 psi with vacuum line disconnected, 36-44 with it connected).
I wish I could stop myself from messing with this thing)@(%&!
Is the FIC firmware up to date?
I checked it not too long ago so I believe it is.
Very interesting thread as I am about to go FI. Think I might think twice about the FIC now. I dont want any of these problems!! Subscribed
Blaine
Blaine
I tried messing with it again this morning.
My idle fuel pressure is ~47.5 psi. That is 4-7 psi higher than stock. I tried setting my fuel map to -50 and it was way too lean (o2 sensors disconnected and ECU reset). I settled on somewhere around -42, then reconnected the o2 sensors. During normal driving is was better, but deceleration and very light throttle it was just as bad (too lean).
I'm fairly certain there's no way to fix all my problems in the FIC's fuel map.
My idle fuel pressure is ~47.5 psi. That is 4-7 psi higher than stock. I tried setting my fuel map to -50 and it was way too lean (o2 sensors disconnected and ECU reset). I settled on somewhere around -42, then reconnected the o2 sensors. During normal driving is was better, but deceleration and very light throttle it was just as bad (too lean).
I'm fairly certain there's no way to fix all my problems in the FIC's fuel map.
Make absolutely sure the firmware is up to date, because the stock firmware doesn't work right with the NSX. I think i recall z110.hex is the right one.
Is the UEGO used to calculate injector pulse, or is it just there to report A/F?
Is the UEGO used to calculate injector pulse, or is it just there to report A/F?
Yeah it has that slave firmware otherwise I don't think it would even work.
THe other firmware says 3.0.
The UEGO is just there for logging purposes.
It will work to some degree. The car will start and idle (and probably run too, to some extent), but AF will be all over the place.
Does the car drive fine (exactly like stock) when you keep it below 3000 RPMs and off boost?
No, that's where it drives like shit. In the opposite situation (above 3000 and on boost) is where it runs great.
The good news is that this really should be an easy thing to resolve...which means the bad news is perhaps something plain isn't working as it should. Focus first on fixing closed loop operation (engine warmed up, below 3000RPMs) and without boost. In this simple condition the car should be operating identical to stock--no timing change, and injector pulse only needs a constant % reduction to compensate for larger injectors...
Below 3000 RPMs no boost the map should have 0 adjustment to spark timing.
Below 3000 RPMs no boost the map should make no adjustments to O2 signals--you want the stock ECU to have accurate, unaltered feedback from the sensors.
The larger injectors require a reduction in pulse, which you've done. The automated pulse calculator is correct at -43% = (1 - (250 / 440)). The FIC tends to round a bit, but that's OK. Your small fuel pressure difference is not an issue in this region. The stock ECU is designed to compensate for variations in fuel pressure by altering injector pulse based on the O2 feedback. That is exactly what the O2 feedback loop is for--to enable the ECU to keep AF tightly straddling a pre-determined value near stoichiometric 14.7.
Sort through it once more. If you've already done all this and are still having such major issues, then something is certainly not working as it should be. It really should be a slam dunk to get the car driving just like stock when in closed loop and without boost.
Above 3000RPMs you enter the open loop mode program. The ECU no longer tries to maintain stoichiometric and pays less attention to the O2 sensors...which is good because you don't have to worry about "fighting with the ECU". But in open loop you have to take more control and you are responsible for the safety of the engine. This is where you need to clamp the MAP voltage, reduce timing and increase injector durations.
Below 3000 RPMs no boost the map should have 0 adjustment to spark timing.
Below 3000 RPMs no boost the map should make no adjustments to O2 signals--you want the stock ECU to have accurate, unaltered feedback from the sensors.
The larger injectors require a reduction in pulse, which you've done. The automated pulse calculator is correct at -43% = (1 - (250 / 440)). The FIC tends to round a bit, but that's OK. Your small fuel pressure difference is not an issue in this region. The stock ECU is designed to compensate for variations in fuel pressure by altering injector pulse based on the O2 feedback. That is exactly what the O2 feedback loop is for--to enable the ECU to keep AF tightly straddling a pre-determined value near stoichiometric 14.7.
Sort through it once more. If you've already done all this and are still having such major issues, then something is certainly not working as it should be. It really should be a slam dunk to get the car driving just like stock when in closed loop and without boost.
Above 3000RPMs you enter the open loop mode program. The ECU no longer tries to maintain stoichiometric and pays less attention to the O2 sensors...which is good because you don't have to worry about "fighting with the ECU". But in open loop you have to take more control and you are responsible for the safety of the engine. This is where you need to clamp the MAP voltage, reduce timing and increase injector durations.
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