I'm having an issues I just can't figure out. I'm pretty new to this but essentially it's an SD only tune because I eventually want to turbocharge it. I'm having an issue when going WOT and about 4800 to 5200 RPM the car sounds like it's bumping up against a rev limiter but according to the log the injectors appear to be maxed out. So I've put long tubes, ported heads, intake, and cam in the car so I thought I might be maxing out the old stock fuel pump so I swapped it for a high flow but that doesn't appear to have been the issue. It does have flow matched GTP injectors on the car so I don't think it's maxing out the injectors. I'm just stumped and wanted to see if anyone could point me in the right direction. I'm attaching the two latest logs. the 76 log has the issue starting at 3:55:14 and the 75 log has the issue at 3:00:11. I also attached the tune I'm running.
Edit: added the files. Apparently wasn't on the desktop site
Last edited by Awesomeness; 3 Weeks Ago at 05:06 PM.
Reason: Add Files
Well I may have answered my own question. I think I'm commanding way too much fuel. It was throwing me off because the histogram is red showing crazy lean and the injector duty cycle is maxed making me believe it needed more. But I think it actually needs less. Not sure why the histo is showing red though because the math should be correct.
This is like all the Greatest Hits all rolled into one...
Having issues, but no mention of what the fuel pressure is, or that it's even been verified. MAF DTCs set to No MIL instead of MIL on First. Wideband lying its little punk ass off. Forced open loop and trying to use the lying-ass wideband for the closed-loop regions. All upstream O2 DTCs turned off (I think, I did not go through the whole list, saw enough to know I didn't need to look more). Not near enough channels being logged to tell what's going on or accomplish anything actually useful. Logging the MAF PIDs when you've specifically told the PCM not to look at the MAF.
Turn the upstream O2s back on, put it back in closed loop, then compare what the trims say to what the WB says.
Thanks for the info. I don't mind the scolding as long as it's constructive and it was very constructive and I appreciated it. I'm just trying to learn as I go. I did get it running much better but after seeing your post I realize there is a lot more wrong than I thought. Also, side note, I see you're in Meridian. I'm actually in Tupelo and I come through there about once a month for work. Small world.
Tuning the closed loop/non-PE parts with the NBs/trims and saving the WB for the open loop parts gives much better results. The NBs/trims will also tattle on the WB, and unless you have a second WB that's known-accurate there's no other way to test it. You can log both trims and WB at the same time in separate graphs, and use filters to exclude the OL parts from the trims graph and exclude the CL parts from the WB's graph.
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