lowered PE and nothing happened?!
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
lowered PE and nothing happened?! ok here is the deal, kinda have two questions here.
first off, will the o2s read higher with headers cause the gasses are hotter in the pipe with the coating? or with them being moved down stream more will they read the same as before headers. i.e. 920 mV will be the same with headers and exhasut manfolds and wont have a different air fuel value.
second, i was runnin about 935mv and felt like the power wasnt there that should have been so i knocked my PE from 1.75% all the way to 0%. my question is how long should it take before the numbers read accurate again? i just went out and after the first run they were 930-950 and aftera few more they are now 920-940. will it take a few days to get the right reading off of them after adjusting this? thanks. i was also eating up a lot of gas so i figured it had to be rich up top, fuel trims are fine.
first off, will the o2s read higher with headers cause the gasses are hotter in the pipe with the coating? or with them being moved down stream more will they read the same as before headers. i.e. 920 mV will be the same with headers and exhasut manfolds and wont have a different air fuel value.
second, i was runnin about 935mv and felt like the power wasnt there that should have been so i knocked my PE from 1.75% all the way to 0%. my question is how long should it take before the numbers read accurate again? i just went out and after the first run they were 930-950 and aftera few more they are now 920-940. will it take a few days to get the right reading off of them after adjusting this? thanks. i was also eating up a lot of gas so i figured it had to be rich up top, fuel trims are fine.
If your WOT trims are zeroed then PE should
act directly, right away. Keep on decreasing PE
until you run into knock retard on the upshifts
and then give it back a little to shut it up.
Colder sensors read higher voltage (as long
as they are hot enough to be working), headers
have way more surface area to dump heat than
stock manifolds and the sensors are located
further downstream so you are probably a lot
cooler than a stocker and this affects readings.
Up on the "flat top" you may have to subtract a
lot of fuel before you see a big voltage movement.
act directly, right away. Keep on decreasing PE
until you run into knock retard on the upshifts
and then give it back a little to shut it up.
Colder sensors read higher voltage (as long
as they are hot enough to be working), headers
have way more surface area to dump heat than
stock manifolds and the sensors are located
further downstream so you are probably a lot
cooler than a stocker and this affects readings.
Up on the "flat top" you may have to subtract a
lot of fuel before you see a big voltage movement.
TECH Resident
Joined: Jan 2002
Posts: 754
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From: USA
Not sure what your trying to do but a 1.75 PE/RPM value equals a commanded AFR of 8.40:1 ( if PE/Temp value is still at 0) which would cause the O2s to run towards max mVolts.
It depends on if the coating was done on the inside or outside as to internal temps and in most cases if they are long tubed headers I find the S1 O2s are placed further downstream causing O2s to report incorrectly, add spicing to O2 wires or breaking the reference airstream path causes O2s to further report incorrectly.
It depends on if the coating was done on the inside or outside as to internal temps and in most cases if they are long tubed headers I find the S1 O2s are placed further downstream causing O2s to report incorrectly, add spicing to O2 wires or breaking the reference airstream path causes O2s to further report incorrectly.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
well i did this with the predator so im not sure waht that first line was regaurding, maybe edit? my o2's are the same distance, i have headers. so will an air fuel gauge casue one to be off?
