AFR issues

Civic 2016+ 1.5 Turbo
Post Reply
Awsomsauce
Posts: 37
Joined: Fri Jun 29, 2018 12:57 pm

AFR issues

Post by Awsomsauce » Wed Sep 12, 2018 11:05 pm

So I’ve turned the boost up and I’m getting a fuel drop. The fuel attempts to hit the cmd fuel but it cuts back to 14 and 15 out of nowhere then comeback. At one point I was WOT, at 22 psi, the cmd was 11.53 and the AFR was 29 like I wasn’t even on the throttle. I have the tune and datalog I can send you if you want to see for yourselves

User avatar
Spunkster
Site Admin
Posts: 17842
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Re: AFR issues

Post by Spunkster » Thu Sep 13, 2018 9:58 am

Post the calibration and datalog showing the issue.

Awsomsauce
Posts: 37
Joined: Fri Jun 29, 2018 12:57 pm

Re: AFR issues

Post by Awsomsauce » Thu Sep 13, 2018 8:06 pm

okay here is the tune and the datalog of the last pass made on this tune.
I increased the target afr in one area because on the previous pass it went lean in that rpm range.
I had also switched the use map for wot to off.

User avatar
Spunkster
Site Admin
Posts: 17842
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Re: AFR issues

Post by Spunkster » Fri Sep 14, 2018 9:22 am

It could be that your wideband sensor is not reading correctly because it is hot or contaminated, or your DI pump could be maxing out at higher boost levels and high ethanol content.

Lilwonton17
Posts: 21
Joined: Wed May 23, 2018 10:53 pm

Re: AFR issues

Post by Lilwonton17 » Sun Sep 16, 2018 3:50 am

Awsomsauce wrote:
Thu Sep 13, 2018 8:06 pm
okay here is the tune and the datalog of the last pass made on this tune.
I increased the target afr in one area because on the previous pass it went lean in that rpm range.
I had also switched the use map for wot to off.
AFR readings of 29 means the injectors turned off for a period of time. I think that is the max value that the AFR can read as far as lean goes. If you are seeing it off the gas coasting while in gear then it's not a problem. But If you are seeing it while accelerating that is a sign of fuel cut.

Awsomsauce
Posts: 37
Joined: Fri Jun 29, 2018 12:57 pm

Re: AFR issues

Post by Awsomsauce » Sun Sep 23, 2018 5:04 pm

Lilwonton17 wrote:
Sun Sep 16, 2018 3:50 am
Awsomsauce wrote:
Thu Sep 13, 2018 8:06 pm
okay here is the tune and the datalog of the last pass made on this tune.
I increased the target afr in one area because on the previous pass it went lean in that rpm range.
I had also switched the use map for wot to off.
AFR readings of 29 means the injectors turned off for a period of time. I think that is the max value that the AFR can read as far as lean goes. If you are seeing it off the gas coasting while in gear then it's not a problem. But If you are seeing it while accelerating that is a sign of fuel cut.
what could be causing a fuel cut. too much ethanol enrichments?

Awsomsauce
Posts: 37
Joined: Fri Jun 29, 2018 12:57 pm

Re: AFR issues

Post by Awsomsauce » Mon Sep 24, 2018 4:54 am

**!! Update! !!**

Okay so I still kept having that miss and drop in the afr even after closing the gap from the stock from Honda plug gap of .030 to .025 which did help reduce the miss and drop but didn’t completely resolve the issue.

So I blended the fuel down. Put 4 gallons of pump 91 octane to a just over half tank of e85. Now there’s no issues.

So Hondata the questions that come to mind are, is the base tunes dumping WAY too much fuel and washing out the spark on full e85 tunes or is there something that is incorrect in the timing tables? I can’t see how reducing the ethanol content would resolve the issue I was having. The only thing that makes sense are the timing and fuel enrichment go up as you go up in ethanol content and come down as you go down.

I’d highly recommend running blended fuel for anyone that cares to read this . Either 40-55 ethanol blend.

D-Rob
Posts: 61
Joined: Tue Apr 29, 2008 6:11 am

Re: AFR issues

Post by D-Rob » Mon Sep 24, 2018 5:41 am

It's likely a misfire related to trying to hang the injector open too long.

The fuel system is too small for a significant amount of ethanol without targeting a leaner mixture.

Awsomsauce
Posts: 37
Joined: Fri Jun 29, 2018 12:57 pm

Re: AFR issues

Post by Awsomsauce » Mon Sep 24, 2018 6:08 pm

D-Rob wrote:
Mon Sep 24, 2018 5:41 am
It's likely a misfire related to trying to hang the injector open too long.

The fuel system is too small for a significant amount of ethanol without targeting a leaner mixture.
I see, thank you everyone for your input on the issue it does not get taken lightly.

Post Reply