8.1 injectors and strangness
07-16-2005, 09:01 PM
#1
TECH Junkie
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8.1 injectors and strangness 1st
I was at 120% duty cycle on injectors so I swapped out the 5.3 stockers for some 8.1l injectors. At the time I was running SD and noticed a good 20-30% duty cycle drop (still could have gone bigger) but these should be satisfactory. Anyway seeing around 17 ms wot instead of 22-25ms with the old. So I finish tuning some SD and turn on the maf and guess what duty cycle goes right back up to around 22ms 120% wot. WTF so Im thinking I need to tweak the maf table.
2nd
Something else strange I noticed today was that running SD my 02 voltage is all over the place at part throttle jumping around by differences of 300 mv then hook back up the maf and its not anywhere near as spuradic varying difference of about 150 mv. Trims levels are about the same SD and with maf.
3rd
strange observation remember Dewanshu's post about the pcm dropping packets well today it is was dropping em like its hot and it was doing it wot. I noticed my fueling would go scary lean like around 180
after it did this.
has anyone found a solution to it dropping packets could it be running hp tuners is causing it?
I was at 120% duty cycle on injectors so I swapped out the 5.3 stockers for some 8.1l injectors. At the time I was running SD and noticed a good 20-30% duty cycle drop (still could have gone bigger) but these should be satisfactory. Anyway seeing around 17 ms wot instead of 22-25ms with the old. So I finish tuning some SD and turn on the maf and guess what duty cycle goes right back up to around 22ms 120% wot. WTF so Im thinking I need to tweak the maf table.
2nd
Something else strange I noticed today was that running SD my 02 voltage is all over the place at part throttle jumping around by differences of 300 mv then hook back up the maf and its not anywhere near as spuradic varying difference of about 150 mv. Trims levels are about the same SD and with maf.
3rd
strange observation remember Dewanshu's post about the pcm dropping packets well today it is was dropping em like its hot and it was doing it wot. I noticed my fueling would go scary lean like around 180
after it did this.has anyone found a solution to it dropping packets could it be running hp tuners is causing it?
07-16-2005, 11:10 PM
#2
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I saw packet drops coinciding with WOT on my
really slow Toshiba but haven't when using good
equipment. But no telling how much other bus
jibber-jabber a gizmo-loaded Escalade has going
on. Wonder whether some of it needs to be shut
off.
really slow Toshiba but haven't when using good
equipment. But no telling how much other bus
jibber-jabber a gizmo-loaded Escalade has going
on. Wonder whether some of it needs to be shut
off.
07-17-2005, 08:07 PM
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Not sure how it works on LS1, but when I did this with the DARK SIDE, we had to recalibrate the MAF for the injectors, only the MAF table was on the MAF, not the PCM. Sounds like you need to change your MAF table to reflect the new injector size.
