I have a 99 Silverado with a sbe 5.3, summit 8715-R1 cam, NNBS/ TBSS intake, return style fuel system 58psi with FIC 775's, aeromotive vac referenced fpr, stock feed, -8 return directly into bulkhead into bucket for no restriction and a walbro 525, shaved 243 heads, 7875 Vs racing.
I copy and pasted the publicly available info you can download from Fuel Injector Clinic for these injectors and also have the information sheet for this specific injector set. The problem I'm having is at idle from a dead cold start the truck fires up decently and starts off lean. As time goes by idling, the inj pw remains 2.5ms (I think is high) but it continues to get very rich, while in closed loop. The commanded AFR, once getting through afterstart enrichment, will settle in at 14.68 and remain there throughout the entire idle log, but the wideband continues to read richer. I've taken logs with both STFT's turned on and off and the STFT's also show the truck running rich throughout the length of the log at idle. I've read through the threads and it seems like the biggest problem people have is securing the proper injector data or inputting it wrong. I'd really appreciate it if someone could look over my log and tune file to see what I'm missing.
Log I'm attaching isn't from a completely cold start, it's the last one i took last night after making another change to offset vs volts vs vac, hoping to correct it, but it illustrates how once the wideband starts to read how it goes from way lean to rich. I also want to add that I'm using map sensor AC Delco 19418810 2 bar from Summit Racing. No specs were provided when i bought it and can't seem to find a linear and offset for that particular 2 bar. I went with the generic 200 linear and 10.33 offset thats provided as the base os upgrade. If anyone thinks that could be part of the problem can you help me figure out the linear and offset.
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