help with low rpm bucking
11-05-2005, 10:24 PM
#1
help with low rpm bucking ok so here is the deal. it seems to only happen at very low map levels, ~30 kpa or so. on decel, i can drop my VE table very low (teens) and it is rich. i can have it in the 40's and its the same richness. it seems that the injectors are only going to about 1.8 ms in those areas and not leaning it out enough. i verified with the WB that it is indeed rich, about 11.5:1.
from what i could tell, trying lower and higher timing, the fuel seems to be the main culprit. once i am out of this range where it goes rich, im fine and the car acts normal. i would really like to fix it but dont know what to do. ive tried to lower the injector pulse width settings and that didnt seem to help. they are 42# ford btw. i have scans to show as well. i will try to post up some pics of the histograms and ve. any advice would be great. i would love to fix this once and for all.
from what i could tell, trying lower and higher timing, the fuel seems to be the main culprit. once i am out of this range where it goes rich, im fine and the car acts normal. i would really like to fix it but dont know what to do. ive tried to lower the injector pulse width settings and that didnt seem to help. they are 42# ford btw. i have scans to show as well. i will try to post up some pics of the histograms and ve. any advice would be great. i would love to fix this once and for all.
11-06-2005, 09:24 AM
#3
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would this at all be related to your DFCO or COT? I read something about someone that was having a similar issue with his truck that had a ls1 in it. Good luck figuring it out!
Nino
Nino
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11-06-2005, 02:45 PM
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did it happen after you made changes to the tune or just out of the blue? if you did reflash, and im only a beginner so bare with me 
Id flash with a tune before the issues started happening and use the compare in 2.0 to see if you accidentilly made a change you should'nt have elsewhere. Good Luck! I may be bugging you on aim once i get back this weekend 
gonna start tuning my baby if she runs after i put her back together. Sucks they blocked aim here on the ship 
Nino
Id flash with a tune before the issues started happening and use the compare in 2.0 to see if you accidentilly made a change you should'nt have elsewhere. Good Luck! I may be bugging you on aim once i get back this weekend gonna start tuning my baby if she runs after i put her back together. Sucks they blocked aim here on the ship Nino
11-06-2005, 05:22 PM
#10
thats cool man just let me know when you need a hand.
and this has always happened. its just strange, the pulse width is only going to 1.8 and i thought it would go a lot lower than that. the min pulse width is set to 1.277 so even with the adder its only about 1.3 ms. but when i pull fuel the injector pulse width stays the same and it still reads rich. unless for some reason. i wish i had a set of smaller injectors to try it out on and see if it fixes it. i know a lot of guys that run 42#ers but never see anyone post with any issue like this. any response i got in the past was to just let it go since im not in those cells driving, well i want **** perfect
lol
and this has always happened. its just strange, the pulse width is only going to 1.8 and i thought it would go a lot lower than that. the min pulse width is set to 1.277 so even with the adder its only about 1.3 ms. but when i pull fuel the injector pulse width stays the same and it still reads rich. unless for some reason. i wish i had a set of smaller injectors to try it out on and see if it fixes it. i know a lot of guys that run 42#ers but never see anyone post with any issue like this. any response i got in the past was to just let it go since im not in those cells driving, well i want **** perfect
lol
11-06-2005, 05:28 PM
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if all fairs well with mine, i could send u my 26#rs. wont be till the following week or so though. you could also PM bombguy99z28 (ben) see if he has an extra set laying around. i know he just went fromt he 26 to 28's.
11-07-2005, 11:59 AM
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will do. im still not sure if i should use my old tune and go off of that or if i should start from scratch. should i call my old tuner up and ask him to email me my stock bin? he should have it right?
11-07-2005, 12:17 PM
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i think i have my bin's here at work. ill load 2.0 on my computer and compare them or send you mine if you like. wont be till later this afternoon though. it was a dyno tune by a shop, so i doubt all the tables were touched. Im almost certain OLFA, DFCO, and majority of the ve was untouched.
