scherejs

iTrader: (12)

every once in a while when i am cruising at highway speeds in fifth my car acts up on me. it happens when i'm doing about 55-65mph in 5th and get on the throttle a little. my car studders bigtime and and ****s itself then puffs huge amounts of black smoke out the back. if i let off then get on it again it tends to not do it again. happens like one in every ten times and only under the circumstances mentioned. never when i drop it down to 4th or 3rd and get the revs up has it done it. thanx jason

Soon2BEVO

iTrader: (41)

Are you stock?

scherejs

iTrader: (12)

3" turbo back w/high flow cat
br air intake
br upper intercooler pipe
safc-II (a/f ratio final value at 11.3)
hallman mbc at 19.5 psi

Soon2BEVO

iTrader: (41)

Dont quote me but sounds like a tuning issue with your fuel. Black smoke is unburned fuel, so the hesitation/studdering problem goes hand in hand with that. I cant really give any more insight, hopefully someone with some better tuning knowledge can chime in!

scherejs

iTrader: (12)

bump

Kevine326

had this issue with my gsx when we were tuning it with the safc.


your running rich at a certain rpm in 5th. Im not very good at tuning the safc but ........

what it sounds like is when you give it more throttle... in safc high throttle above 55%? it is running rich. It hasnt been tuned for 5th gear using high throttle... at least what it sounds like to me.

the black smoke is indicative of running rich and with the safc i can pretty much bet the above is what it is. When it was tunned "they" forgot or didnt set correctly 5th for high throttle.

edit: if you have a a/f ratio gauge or a turbo timer like the apexi you can see what your running in a/f ratio. You can use this to tune in upper 5th.. and figure it out. I dont remember what it is under in the safc except hi-throttle and you can lower it at the rpm your having issues at. BUT I wouldnt screw with this unless you know what your doing.... you could lower your gas input to low and have knock!