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only ero's
August 16th, 2014, 12:54 PM
I have been having an issue for a while with my car. My car was seeing a rich state on the wideband at both an idle and and an extreme rich condition under deceleration. You could also definitely smell it too. I was seeing AFR’s in the 12.2-12.4 range at idle and it would be 11.2-11.4 (all on a gas scale) under deceleration. The AFR's are a little rich under WOT. I had gone into EFIlive and attempted to change the VE table for the idle but never saw a change in the AFR’s so I put it back to the original. The car is tuned with a COS3, an E85 car and my wideband is in the driver's side exhaust, after the turbo downpipe. I had recently bought a new O2 sensor for my wideband.

Recently, I hooked up a second wideband and put this one in the passenger exhaust. I wanted to see what it would show, as well as compare to my current wideband. At idle, I saw typically right around stoich AFR at idle and under deceleration. It was not matching the readings from my original wideband. I reduced fuel in those cells of the VE table and saw the changes in the passenger bank. I switched the tune back just for consistency.

I disconnected the second wideband, and put both in the drivers side exhaust. Both widebands read the same reading, and ruled out any issue with my wideband. I am seeing a rich state on the drivers side and a stoich condition on the passenger side. With the car idling, we would disconnect one injector on the driver’s side and see the AFR go from 12.2 to about 14.5. Reconnect that injector, and try another on the driver’s side and same thing. It ended up doing the same on each injector on the driver’s side. I am guessing one or more of the driver’s side injectors are gunked up (1,3,5,7). I am running FIC2000 injectors and they are known to have issues with E85. I sent the injectors off and were cleaned from Fuel Injector Connection. Got them back, fired up the car and the same exact thing is happening. Rich on the driver's side and around stoich on the passenger's side.

I am really new to tuning and still trying to learn. I believe mine is setup for open loop (I could be wrong on this). Just for sh*ts and giggles, we disconnected the front O2 sensors (installed in the Y-pipe) and didn't see any change in the rich state.

I am not sure what to do or where to go. I am going to send FIC another email to see what they think. I don't believe EFI Live can adjust fueling on just one bank. Just looking for any recommendations.

I am attaching my tune file in case there are things to check in there. I tried to post as much info as I can in here for background info.

Please don't tear the tune too far apart. I took the car and had it tuned, and it works but I am not very impressed with what I see in the tune. I think there are a LOT of things I don't agree with, and I need to iron out/fix. I plan to change those things after I get this fueling issue worked out.

17329

statesman
August 16th, 2014, 07:39 PM
I am really new to tuning and still trying to learn. I believe mine is setup for open loop (I could be wrong on this).

Yes, you are wrong on this. Your tune is setup for closed loop.

To go open loop, change all values in {B4205} to 140.

only ero's
August 17th, 2014, 03:57 AM
Yes, you are wrong on this. Your tune is setup for closed loop.

To go open loop, change all values in {B4205} to 140.

I agree with you on that. I have noticed you need to set those in the tutorials to force Open Loop.

Where I am confused is by {B3801} (Long Term Fuel Trim Correction) and {B4801} (STFT Idle Enable) both being disabled.

statesman
August 17th, 2014, 05:08 AM
It goes into closed loop when you hit the temperature in {B4205} and short term fuel trim corrections happen from then on. When you hit the temperature in {B3802}, long term fuel trims can be updated if {B3801} is enabled. {B4108} determines which tables are used to calculate the STFT at idle... disabling it only changes the tables which are used. Click on it and read the description to see which tables are used when enabled or disabled. You'll still be in closed loop with STFT corrections being applied.

5.7ute
August 17th, 2014, 02:20 PM
Log the injector pulse widths & fuel trims for each bank. That will tell you if the pcm is commanding more fuel or if there is a mechanical issue.

only ero's
August 17th, 2014, 10:46 PM
Log the injector pulse widths & fuel trims for each bank. That will tell you if the pcm is commanding more fuel or if there is a mechanical issue.

Thank you for the response. I will try to get to this later this week. It is raining today and I have a business trip on Tuesday and Wednesday.