sputtering under light load
07-09-2005, 10:55 AM
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sputtering under light load I'm currently tuning in SD mode and got the car to idle and it feels good WOT. Part thottle on the other hand is driving me nuts. Under light throttle the car sputters..it almost feels like a lean miss. Anything more than 1/4 throttle and it acts fine. How do I fix this problem?
My LTrims are +10 - +16 part throttle and I can't seem to lower them. I don't think its a mechanical problem, but more of a tuning issue. There are no vaccum leaks and I messed with the VE table and at one point fixed the low end problem then it started to sputter at 1/2 throttle. I just can't win...
Any insight on this would be great.
My LTrims are +10 - +16 part throttle and I can't seem to lower them. I don't think its a mechanical problem, but more of a tuning issue. There are no vaccum leaks and I messed with the VE table and at one point fixed the low end problem then it started to sputter at 1/2 throttle. I just can't win...
Any insight on this would be great.
07-11-2005, 09:08 AM
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Also check your MAF sensor. If it is descreened and you use a K&N (or any oiled filter for that matter) you could have over-oiled and dirtied it. From what I have recently learned, at low RPM it's much more sensitive.
07-11-2005, 11:25 AM
#7
yeah i forgot about that lol guess thats why i never mentioned it in my first post. you have a 2002? so only the primary ve table right? maybethe maf is not failing itself out cause if you change the ve with no changes in the trims it would make sense if the maf was still reporting numbers
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07-11-2005, 11:27 AM
#8
If he disabled the maf it shouldn't come into play at all. Make sure the map appears to be working, o2's swinging ect. Check out the injector pulse width when its sputtering, is it above or below 10ms or really low single digits, that should give you a rough idea if its a rich or lean condition causing the problem.
Last edited by SmokingWS6; 07-11-2005 at 11:38 AM.
07-11-2005, 11:39 AM
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Just because he failed the maf doesnt mean he is in SD mode. I have seen a few cars not fall over after setting the fail to 0. Got tired of waiting and unplugged it....
07-11-2005, 01:52 PM
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plus when i plugged it up and unplugged it the afr cahged accordingly and i was dyn cyl air and the maf reading still matched even though the ve table was different and was reading different for the same cells at idle
07-14-2005, 06:59 AM
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I don't run a MAF at all. It's removed and set to fail. I got tired of messing with LTrims and all that junk after 2 straight days of wasting my time.
Running the car in open loop now, no more sputtering problems
Running the car in open loop now, no more sputtering problems
06-22-2010, 12:55 PM
#18
im have the same problem on my lq4 with the t70....and they are lean spikes accoriding to my wide band. i also some times get rich spikes when talking out.any suggestions?
have 60lbs injectors and stock everything with maf
have 60lbs injectors and stock everything with maf
