Boosted 5.3 misfire in boost
09-27-2013, 06:05 PM
#1
Boosted 5.3 misfire in boost It honestly feels like I am hitting a rev limiter. It is a little fat, but not overly so. But when going into load/boost it stumbles badly and misfires. It sometimes will pull through and clean up, but not sure why it is happening. I just changed out the plug wires to try to eliminate that. Next comes the plugs. Here is the scan and tune. It is a work in progress and my first boost ls motor, so be gentle 
Let me know if you see anything out of the ordinary.
Let me know if you see anything out of the ordinary. 
09-28-2013, 12:10 PM
#4
Plugs were ok. Going to try adding some grounds and running a better wire from alternator to the battery. For questions I got on hptuners, I never went wot as it was breaking up so bad. I was trying to roll into it. Also the injectors are scaled in half to add more resolution to the tune.
09-28-2013, 01:27 PM
#5
Added a ground and made the old ground better and cleaned them all off. Ran a better wire for the alternator to the battery so I have better voltage. Changed the plugs and still same thing if not worse. Getting quite frustrated on this one.
09-30-2013, 08:20 AM
#7
It was yes and actually before boost came on slightly. I did lean it out and was able to get some almost clean pulls before I scrubbed a tire on the rear fender and took a nice slice out of the rear tire.....doe! I am thinking at this point I have a mild exhaust leak (can hear it and see a little carbon) that is causing the wideband to read leaner than it actually is. When I go mid to low 11s on the gas scale it cleans up a good bit.
Last edited by Sarg; 09-30-2013 at 03:59 PM.
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09-30-2013, 07:28 PM
#9
Yeah I think at this point the wideband is giving a falsely lean reading. I would not think this would happen with the backpressure in the exhaust, but I guess it is? I had a coupler blow off and was able to see how it reacted in NA form on the way home. It was hitting 10.8 in NA form right before boost would have set in, like 101 kpa. I have tried both factory wires and now Taylor wires.