Need help with identifying exhaust leak
 

Hello,
I just recently installed my Openflash Headers and flashed my car to the stage 2 UEL tune. I am pretty new to the whole OFT, but I decided to data log afterwards and took a short drive and noticed my LTFT was really high. after looking around the forums, I learned this means I'm running very lean. Could this be because of an exhaust leak in the connection to either engine or overpipe?

Here are the datalogs, there are 3 short trips in one log.

http://www.datazap.me/u/ticowalrus/l...8?log=0&data=1

Any help/info would be greatly appreciated!

Thanks!

Check your O2 sensor.

something weird is going on with the logging, at times, looks more like logging issue that car issue.
connect you oft to internet and let it upsat make sure your on latest version of openflash manager 1.21.0 i think.

then try logging again

high ltft doesnt mean you running lean it just means the ecu is applying a lot of correction to try to get the correct afr, this couls be due to bad maf scaling due aftermarket intake or exhaust leak ect or wrong fuel ie e85 on a petrol tune.

parts of log look ok but then some parameters are weird ie iam=0 and then ltft -100, thats impossible max is 30, looks like logging problems

I was actually about to do that today because I felt the O2 sensors might have not been threaded properly. I attempted to thread them in, but they only went in so far. I did not want to damage them. I assumed that was as far as they would go on this header. Do they go in completely like in the stock headers? If so, any tips on how to help them go in all the way/properly?

I believe that sudden drop with ridiculous numbers was from when I stalled at a light due to the dead spot after tuning. However, i updated my OFT and did a log today on the way back from home. The LTFT has gone down, but are still pretty high, in the 12-15 range. Here is the log:

http://www.datazap.me/u/ticowalrus/l...og=2&data=1-11

Do you think its a logging issue still? I am going to check my O2 sensors late today as advised by phrosty to cover all bases.

Yes 02 sensors should screw in all the way easily If they don't then dont force them.
remove 02 sensors and run a M18 by 1.5mm pitch thread tap/chaser through the 02 sensor bungs in header they often distort a bit when welded in.
02 sensors will then screw in easily all the way.

Yes it looks like you have a leak in exhaust near or at sensors. High LTFT positive at idle and low rpm then ok higher rpm.

you also have a car than runs quite rich on oft maf scaling it going to 11.25 which is limit of o2 sensor rich wise. above 3500 rpm.

you would benifit from adjusting maf scale, or copying in one from here

http://www.ft86club.com/forums/showthread.php?t=94822


but fix o2 sensor/exhaust leak first



.

I got under the car and reinstalled the headers again. when uninstalling, saw black on one of the ports to the manifold, and to be safe i tightened my O2 sensors again, reinstalled everything, and tightened. I took a couple logs diving around. Do these look like the normal readings i should be getting?

http://www.datazap.me/u/ticowalrus/l...ta=1-2-9-10-11
http://www.datazap.me/u/ticowalrus/l...=1&data=1-9-11

And thanks for the info on the MAF scaling, I will definitely look into it!

looks a lot better.

did you use new gaskets ?, if you reuse old ones it will generally leak after a while. They only crush to shape once.

I used my new pair of grimmspeed header gaskets, but I re-used the gasket connecting to the overpipe. Is there a specific name for that gasket so I can look it up to buy?

Sent from my SM-G920T using Tapatalk

just header to overpipe gasket i believe

Ok, great! Thanks a lot for your help with everything! Really appreciate it! :)

Thanks for the link! :)