Quick Fuel trim Question
#1
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Quick Fuel trim Question
At idle my Long Term, fully warmed up is 125
At WOT it hits 150 and doesnt go any higher or lower..
this normal?
not even 100% what it all means..
At WOT it hits 150 and doesnt go any higher or lower..
this normal?
not even 100% what it all means..
#2
Senior Member
True Car Nut
Matt, Here'* a pretty good article that exlplains fuel trim in understandable terms. Worth a read...
Ross-Tech, Fuel Trim Explained
Something seems pretty fishy with the long term trim values you are reporting. As the article states and from my personal experience scanning mine, your trim should center around zero. Huge positive trims indicate something wrong, IMO (Note that I could be wrong) and could indicate a severely lean situation or maybe even a bad MAF.
Please keep in mind that I have no personal experience with trim levels and their possible connotations and am only interpreting, based on what I've read.
Ross-Tech, Fuel Trim Explained
Something seems pretty fishy with the long term trim values you are reporting. As the article states and from my personal experience scanning mine, your trim should center around zero. Huge positive trims indicate something wrong, IMO (Note that I could be wrong) and could indicate a severely lean situation or maybe even a bad MAF.
Please keep in mind that I have no personal experience with trim levels and their possible connotations and am only interpreting, based on what I've read.
#3
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Here'* another article on fuel trims with a bit of different info:
Fuel Trims
BTW, thanks! I'm learning some stuff here. :thumbsup:
Fuel Trims
BTW, thanks! I'm learning some stuff here. :thumbsup:
#5
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What are you gauging it with, I also learned you should be around 0 - plus or minus a few.Maybe you are gauging it differently.
#7
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Interestingly, there'* something to be learned about fuel trim by reading this thread:
http://www.bonnevilleclub.com/forum/...asc&highlight=
If you get past the argument/discussion at hand in that thread, it indicates that your long term trims are way too high at WOT and that you're probably running too lean there. Above where your pCM can correct for it. Are you getting KR?
As I know that you have done a bunch of work on your engine, diagnosis will depend a lot on your knowledge and input.
Again, realize that I have no firsthand experience with this, but I can read and apply. More specific input will have to come from the few here who are personally experienced.
http://www.bonnevilleclub.com/forum/...asc&highlight=
If you get past the argument/discussion at hand in that thread, it indicates that your long term trims are way too high at WOT and that you're probably running too lean there. Above where your pCM can correct for it. Are you getting KR?
As I know that you have done a bunch of work on your engine, diagnosis will depend a lot on your knowledge and input.
Again, realize that I have no firsthand experience with this, but I can read and apply. More specific input will have to come from the few here who are personally experienced.
#8
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I pull 6 degrees of KR at WOT with my smaller pulley on the SC, i pull 0 degrees of Kr with the stock pulley.
It does NOT run that nicely top end wth the small pulley, infact, my exhaust manifolds will turn red at WOT.
indicating some kind of lean condition, regardless of what the 02 is telling me.
Under even say half throttle it pulls 0 kr, however you can tell it has to work its way through the 3000-4000 rpm band like it does it in stages.
this is Long Term trim as well.
It does NOT run that nicely top end wth the small pulley, infact, my exhaust manifolds will turn red at WOT.
indicating some kind of lean condition, regardless of what the 02 is telling me.
Under even say half throttle it pulls 0 kr, however you can tell it has to work its way through the 3000-4000 rpm band like it does it in stages.
this is Long Term trim as well.