rich misfire? lean afr reading

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wrenchdad
Master MS/Extra'er
Posts: 614
Joined: Mon Feb 14, 2005 5:30 am
Location: Natchez, Mississippi

Re: rich misfire? lean afr reading

Post by wrenchdad »

Just a quick look, but I would suggest adding fuel, seeing you are running ITBs, trying doubling your accel % through the whole range and see if the gets better or worst.

later wd
kaeman
Master MS/Extra'er
Posts: 643
Joined: Sun Nov 06, 2005 12:31 am
Location: NORTHERN CALIFORNIA

Re: rich misfire? lean afr reading

Post by kaeman »

Hey Wrench,
I have been removing fuel and the engine seems to be getting better. I just wanted some other opinions on that section of the fuel table. the more fuel I have removed, the better the acceleration has been and the smaller stumble. It used to be if I stabbed the throttle below 1500 rpm the engine would occasionally stall and I would have to restart. now the stumble is a small cough and hesitation then it takes off.. I am just noting the fuel pulse width during the lean spike and it is the most fuel the engine receives in the entire log. which is why I am thinking misfire. if you see the third log the engine runs great, its accelerating pretty fast and has no misfire/lean spot. (also not hitting the accel enrichment low limit)
64 el camino, 383 SBC, 11.7 to1 CR, accufab tb/rhs intake, 44lb injectors, trick flow heads, xr292r solid roller cam, belt drive camshaft, dry sump oil system, 2400 stall, turbo 350, spooled 9 inch, strange axles, 3.89 gears, dual wideband, full sequential fuel/cop, MS3x using 1.4.1 code.
wrenchdad
Master MS/Extra'er
Posts: 614
Joined: Mon Feb 14, 2005 5:30 am
Location: Natchez, Mississippi

Re: rich misfire? lean afr reading

Post by wrenchdad »

Go with what works I always say!!

THE best thing I did for accel is turn on EAE, I haven't really got it completely worked out yet but it help a lot on the right off idle stuff with my ITBs with the default settings

later wd
kaeman
Master MS/Extra'er
Posts: 643
Joined: Sun Nov 06, 2005 12:31 am
Location: NORTHERN CALIFORNIA

Re: rich misfire? lean afr reading

Post by kaeman »

thanks WD. I think I will try to remove some more fuel tomorrow, but I think I will make a fairly large change in the section of the ve table at 90 kpa and above in the 1100 and 1400 bins... going to try dropping about 8 full points from those bins. then datalog my test drive. I would love to see a change in the afr reading and lose that misfire.
this is the msq I am going to install tomorrow or Saturday.
idle stumble fix.msq
64 el camino, 383 SBC, 11.7 to1 CR, accufab tb/rhs intake, 44lb injectors, trick flow heads, xr292r solid roller cam, belt drive camshaft, dry sump oil system, 2400 stall, turbo 350, spooled 9 inch, strange axles, 3.89 gears, dual wideband, full sequential fuel/cop, MS3x using 1.4.1 code.
kaeman
Master MS/Extra'er
Posts: 643
Joined: Sun Nov 06, 2005 12:31 am
Location: NORTHERN CALIFORNIA

Re: rich misfire? lean afr reading

Post by kaeman »

I have been adding more resolution to the ve table bins and now I am going to table switching to increase the load bins... I think this will make my life simpler.... I have found several places where the low rpm high kpa bins had way to much fuel.. this new tune should make my tuning easier because of the bin resolution improvements.
2014-09-03 table switching.msq
64 el camino, 383 SBC, 11.7 to1 CR, accufab tb/rhs intake, 44lb injectors, trick flow heads, xr292r solid roller cam, belt drive camshaft, dry sump oil system, 2400 stall, turbo 350, spooled 9 inch, strange axles, 3.89 gears, dual wideband, full sequential fuel/cop, MS3x using 1.4.1 code.
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