Hunting idle, AFR

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MaddMartigan
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Hunting idle, AFR

Post by MaddMartigan » Sun Aug 10, 2014 4:51 pm

OK, so I have my Innovate LC-1 wired in (and that's a separate thread I won't post now) and datalogging with Binary Editor. I have the car running. The problem I'm seeing is that the car seems to be hunting for an idle and the AFR is bouncing around a lot. I'm using the MAF curve for the Lightning 90mm and I haven't changed that. I'm using Decipha's T4M2 base tune with modifications for my injector size (42lb. FRPP) and the other parts that are different from a SN95 setup. Can anyone give me some tips on how I go about changing the tune just to smooth out the idle or direct me to a FAQ or doc that explains the process a little more clearly?

TIA
1993 Ford Thunderbird LX, T4M0 EEC-IV, CHP 347, TFS TW's, TFS stage 1 cam,42# inj, 90mm LMAF, 1 5/8 Mac Long Tubes, 3.73 gears, built AOD w/ 9.5" TC, AEM EMS, LC-1 WB O2 and a few other things.

decipha

Re: Hunting idle, AFR

Post by decipha » Sun Aug 10, 2014 11:20 pm

with them longtubes youll probably have to disregard the o2s at idle and force open loop

then just adjust fuel until she happiest, that should tame the idle, then dial in the idle air

it would be best to dial in the part throttle and WOT fuel first that way you dont have to double work yourself

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Re: Hunting idle, AFR

Post by MaddMartigan » Mon Aug 11, 2014 8:07 am

OK. That does make sense. I have a couple of points I don't quite understand.

1. The car definitely appears to be running very rich at startup since it's smoking a bit but the wideband sensor is showing AFR that's pretty lean most of the time. I realize that my wideband sensor is pretty old and that I may have to replace it but I'm not quite sure. I also realize that it's located about 6-8 inches after the collector in the long tubes. I'm not sure which would be the case really. My narrowband sensors are showing stoich like you said so I know I can't really rely on them. I guess I'm unsure of why I'm seeing the wideband bounce around so much. It seems like the injector pulses are bouncing a lot.

2. I read your article on adjusting the fuel and I can't find FN1307 in BE. Am I missing something on that?

Since the car has been sitting so long, do you think I should change the spark plug wires? I have MSD 8.5mm wires in it. I know this sounds cheezy but I have a color scheme that I'm trying to maintain in the car so I'm trying to keep the wires either red or black so if there is a brand of wire that you recommend over MSD I'm listening as long as I can get it to match my color scheme.

I may end up taking you up on the online tune service but I think I need to make sure I have all of my ducks in a row first. I don't have the car road legal right now (registration, insurance, tires) so I'll need to make sure I'm ready before I do that.
1993 Ford Thunderbird LX, T4M0 EEC-IV, CHP 347, TFS TW's, TFS stage 1 cam,42# inj, 90mm LMAF, 1 5/8 Mac Long Tubes, 3.73 gears, built AOD w/ 9.5" TC, AEM EMS, LC-1 WB O2 and a few other things.

XantheFIN
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Re: Hunting idle, AFR

Post by XantheFIN » Mon Aug 11, 2014 8:25 am

MaddMartigan wrote:OK. That does make sense. I have a couple of points I don't quite understand.

1. The car definitely appears to be running very rich at startup since it's smoking a bit but the wideband sensor is showing AFR that's pretty lean most of the time. I realize that my wideband sensor is pretty old and that I may have to replace it but I'm not quite sure. I also realize that it's located about 6-8 inches after the collector in the long tubes. I'm not sure which would be the case really. My narrowband sensors are showing stoich like you said so I know I can't really rely on them. I guess I'm unsure of why I'm seeing the wideband bounce around so much. It seems like the injector pulses are bouncing a lot.

2. I read your article on adjusting the fuel and I can't find FN1307 in BE. Am I missing something on that?

Since the car has been sitting so long, do you think I should change the spark plug wires? I have MSD 8.5mm wires in it. I know this sounds cheezy but I have a color scheme that I'm trying to maintain in the car so I'm trying to keep the wires either red or black so if there is a brand of wire that you recommend over MSD I'm listening as long as I can get it to match my color scheme.

I may end up taking you up on the online tune service but I think I need to make sure I have all of my ducks in a row first. I don't have the car road legal right now (registration, insurance, tires) so I'll need to make sure I'm ready before I do that.
I think he means FN1360 on year 92+? (RPM + PERLOAD). It is renamed.
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MaddMartigan
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Re: Hunting idle, AFR

Post by MaddMartigan » Mon Aug 11, 2014 8:26 am

OK, that makes sense then. I am using a T4M0.
1993 Ford Thunderbird LX, T4M0 EEC-IV, CHP 347, TFS TW's, TFS stage 1 cam,42# inj, 90mm LMAF, 1 5/8 Mac Long Tubes, 3.73 gears, built AOD w/ 9.5" TC, AEM EMS, LC-1 WB O2 and a few other things.

decipha

Re: Hunting idle, AFR

Post by decipha » Mon Aug 11, 2014 10:11 am

1360 is stabilized fuel, thats disabled in all my tunes, the table you'd be looking to adjust for startup enrichment would be the startup ol table but you don't need to adjust that either

you need to dial in the maf or injector info to get her leaned out at idle

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Re: Hunting idle, AFR

Post by MaddMartigan » Tue Aug 12, 2014 7:22 pm

OK, I think I basically figured this out. It has been over 6 years since I have worked on this car or any car like it all. My skills were beyond rusty. The bottom line was that I had base timing way off and the ECU was doing it's best to adjust but obviously it can't adjust that far.

I'm on my way to getting this going really well. Thanks to Decipha for a tune that really gets me started.
1993 Ford Thunderbird LX, T4M0 EEC-IV, CHP 347, TFS TW's, TFS stage 1 cam,42# inj, 90mm LMAF, 1 5/8 Mac Long Tubes, 3.73 gears, built AOD w/ 9.5" TC, AEM EMS, LC-1 WB O2 and a few other things.

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