Injector Duty Cycle Drops
#1
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my WOT in NA or Nitrous has been making a rapid chit,chit,chit, sound at the top end of WOT after i changed my plugs 2 days ago.
I logged that my inj DC was at 52% when the sound comes on and then my inj DC takes a dump down to 3% then recovers to 52% and takes a dump again down to 3%. This time there was a bad noise after the chit sound so i let off. that bad noise is probably when my DC took a dump.
could it be a bad plug that causes the inj DC to dump? or is it the injectors? i made changes to the maf and ve today and also disabled COT.
i have a 00 SS a4 stock with 37lb lucas injectors. the injectors were bought used and i've been having a problem tuning them. on an 85 shot dry spray, my inj DC only goes 5% more than when NA. so maybe the injectors are bad? or is it a bad plug(s)?
please help.
here is a scan of the DC taking a dump at 11 and a half minutes.
I logged that my inj DC was at 52% when the sound comes on and then my inj DC takes a dump down to 3% then recovers to 52% and takes a dump again down to 3%. This time there was a bad noise after the chit sound so i let off. that bad noise is probably when my DC took a dump.
could it be a bad plug that causes the inj DC to dump? or is it the injectors? i made changes to the maf and ve today and also disabled COT.
i have a 00 SS a4 stock with 37lb lucas injectors. the injectors were bought used and i've been having a problem tuning them. on an 85 shot dry spray, my inj DC only goes 5% more than when NA. so maybe the injectors are bad? or is it a bad plug(s)?
please help.
here is a scan of the DC taking a dump at 11 and a half minutes.
#2
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could this be a rev limiter fuel cut off? normally the car shifts at 6k but it looks like in the log i am momentarily hitting 6186 and 6277 rpms before the injectors DC drops. i've never seen above 6100 rpms before this scan
here is a pic of the scan the top row in white is the inj DC.
here is a pic of the scan the top row in white is the inj DC.
#3
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If you haven't changed the limiter, the stock setting is 6200. That would make sense as the limiter cuts fuel. It may be time to alter shift points or increase shift firmness. The 4L60E wasn't designed for nitrous, so it may be on it's way out.