#50419, "backfiring problem and spark plug pics(56k warn)"
ok since i put in my new o2(2 days ago) the car has been running pretty good. i had to retune it though, and my idle fp's are down to around 21psi at idle where w/ the old o2 it needed to be at least 24psi. anyway, even at 21psi my ltft is close to -25 most of the time, however my o2 readings at WOT are only at .92 and sometimes lower. that reading is according to my datalogger. according to my o2 gauge, the volts are at .95ish at WOT, so i don't know what to believe, b/c my fuel trims are pretty leaned out. anyway, just yesterday i started getting little backfires during deceleration. it was never a smooth sound, but now there are noticeable pops and sometimes rather loud ones. i figured it was my plugs and changed them, but it still does it. what could it be? is it possible that i'm still running really rich? or could i be running very very lean? my fuel trims and o2 volts are contradicting. my egts seems ok, i get close to 800C on 3rd gear pulls, but don't get any detonation. looking at my plugs though, i don't think i'm running extremely rich, b/c the tips are definitely not black. the white color of them actually scares me a little. it looks like im' running very hot. how do u guys think they look?
#50428, "RE: backfiring problem and spark plug pics(56k warn)" In response to Reply # 2 Jun-12-03 07:29 PM by siueclipse
looks to me like you are running too rich.
i currently have my base fuel pressure set to 19psi. however my boost fuel pressure is way to high, (getting a vortech soon). whenever i turn the boost up past 12psi i backfire.. miss.. etc.. the usual running too rich sounds..
#50429, "RE: backfiring problem and spark plug pics(56k warn)" In response to Reply # 3 Jun-12-03 07:54 PM by 97eclipseRS
what'ya think about the white plugs though? isn't that a result of running too hot? i'll try and turn down my fp's a bit tomorrow. i'm just afraid to b/c of my contradicting WOT o2 readings. the car runs smooth under acceleration, it's only under decel that it backfires.
#50431, "RE: backfiring problem and spark plug pics(56k warn)" In response to Reply # 0
Its really hard to tell without looking at them, but to me its almost like the insulators have an oily film or residue on them? Do you burn any oil at all, under boost or vacuum? The center insulators should be a whitish/tan color, and the electrode tips on yours are a bit burnt looking. Those plugs def aren't normal looking plugs. Usually, backfires when you let up off of the gas, if out the exaust, means you are too rich, or for some reason, you have an excess amount of fuel trying to be burnt. I dont know, its hard to tell without looking at them in person, but do you have any signs of oil burning?
13.5 @108 MPH-2.2 60ft(stupid FWD!) S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential fuel injection) My webpage: http://eclipsed4evr.home.comcast.net -1998 Mitsubishi Eclipse RS-T- "Toy" -1992 Plymouth Laser Turbo AWD(SOLD) -2000 Honda CR-V(daily)
#50593, "RE: backfiring problem and spark plug pics(56k warn)" In response to Reply # 6
i promise you, you are running too rich. the hrc system was not designed to run with 310cc injectors. furthermore the craptech fpr can't be adjusted under boost with those injectors either.
Search
Printer-friendly copy
1 User in Chat
