LTFT numbers and o2 numbers
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
LTFT numbers and o2 numbers well i was lookin at my LTFT and saw both at about 10-12% at WOT and running in 4th gear at 60 mph about 3000 rpm also at 60 mph in 6th gear. im not too firmiliar with what this means can you help me out? also i see the o2 numbers at WOT hover around 890-940 but its kinda hard to get it to read constant. i sent me predator back to get it recalibrated with the mods that i have in my sig and i got it back and it just doesnt feel as fast. the only difference was my LTFT were at about 5-6% before. anyone have any idea what i can possibly do to get some more pep out of it and please let me know what the LTFT numbers mean? thanks guys
Re: LTFT numbers and o2 numbers + LTRIMS means the car dumps fuel at WOT cause it THINKS you are lean
do you have a ported MAF? You cant tune a car by WOT LTRIMS either. You need to get a idea of what they are cruising around. Again you want them slightly negative(0 to -3 range). Mine average from 0 to +4 but im happy with them there
do you have a ported MAF? You cant tune a car by WOT LTRIMS either. You need to get a idea of what they are cruising around. Again you want them slightly negative(0 to -3 range). Mine average from 0 to +4 but im happy with them there
Re: LTFT numbers and o2 numbers means you need to richen your car. I see you have the SLP MAF and smooth bellow. Even though the SLP MAF is calibrated it still runs the car a tad lean. I know a ported TB would richen the car back up a bit and probably make the LTRIMS about 6-7% cruising.
Simple fix would be to pull up the MAF table on edit'
highlight the 3000-6000cells and mult by 110%, then scale down the cells after that untill you hit 100%
example 6000 x 110%, 6100 x 109%, 6200 x 108% on down untill 100% so it levels out the table
i know 6000, 6100, and etc arent the correct mhz's but its just for a general idea what to do
that should bring your LTRIMS to 0 or CLOSE when at cruise rpms
Simple fix would be to pull up the MAF table on edit'
highlight the 3000-6000cells and mult by 110%, then scale down the cells after that untill you hit 100%
example 6000 x 110%, 6100 x 109%, 6200 x 108% on down untill 100% so it levels out the table
i know 6000, 6100, and etc arent the correct mhz's but its just for a general idea what to do
that should bring your LTRIMS to 0 or CLOSE when at cruise rpms
Re: LTFT numbers and o2 numbers He's using the Predator - you can't do it with edit overtop!
Predator can do this for you - they brought mine down by editing the MAF table. You have to talk to them and let them know what average LTFTs you have.
Why are you sending it back to them? They sent me programs in an e-mail and I downloaded them into my Predator.
Predator can do this for you - they brought mine down by editing the MAF table. You have to talk to them and let them know what average LTFTs you have.
Why are you sending it back to them? They sent me programs in an e-mail and I downloaded them into my Predator.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers i have been fighting over getting it to work over email but i cant get it to work. so any suggestions would be great.
ok my LTFT are running about 9.38% going down the road at 60 mph. but my o2 numbers are right at 900 so that should be good. what do i need to do to get these numbers down for LTFT? i have 0% knock retard until i back off is that cool? i was messing with the PE and it screwed up the o2 numbers. i put the stock program back in there to see how it was. my o2 is running OK at about 880 maybe too lean and the LTFT is 7%.
i went to put the tuning they gave me back in and it said some kind of time error or whatever and booted me out. why is this? so it looks like my air fuel is good by the o2 numbers but the LTFT is high. what do i need to do? and would i benefit from any more advanced timing? it just doesnt feel like i have the same amount of response as the first time i did it before i sent it off. and i dont wanna screw anything up on my car. i went back to restore so should i just leave it like that until i can get a new program? that is the stock tune right? and why isnt it going back to the program they gave me? sorry so long! please any comments would help a lot!
ok my LTFT are running about 9.38% going down the road at 60 mph. but my o2 numbers are right at 900 so that should be good. what do i need to do to get these numbers down for LTFT? i have 0% knock retard until i back off is that cool? i was messing with the PE and it screwed up the o2 numbers. i put the stock program back in there to see how it was. my o2 is running OK at about 880 maybe too lean and the LTFT is 7%.
i went to put the tuning they gave me back in and it said some kind of time error or whatever and booted me out. why is this? so it looks like my air fuel is good by the o2 numbers but the LTFT is high. what do i need to do? and would i benefit from any more advanced timing? it just doesnt feel like i have the same amount of response as the first time i did it before i sent it off. and i dont wanna screw anything up on my car. i went back to restore so should i just leave it like that until i can get a new program? that is the stock tune right? and why isnt it going back to the program they gave me? sorry so long! please any comments would help a lot!
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers when i check the LTFT do i wanna be on the gas or off the gas? and wouldnt the ram air cause it to wanna correct it more? my MAF is about .75-.78 at idle if taht helps anything. i read u mentioned it so i figured i would throw that in too lol
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Re: LTFT numbers and o2 numbers crap, my bad.. i thought you had edit 
Ltrims need to be studied at part throttle. The PCM takes the last LTRIM reading before WOT and thar reading tells the PC to add or not to add fuel. If you LTRIMS are 0 at WOT then it isnt adding any fuel. If they are +0 then its adding fuel. But you need to use the part throttle and cruising ones to tune the car...
Ltrims need to be studied at part throttle. The PCM takes the last LTRIM reading before WOT and thar reading tells the PC to add or not to add fuel. If you LTRIMS are 0 at WOT then it isnt adding any fuel. If they are +0 then its adding fuel. But you need to use the part throttle and cruising ones to tune the car...
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Verdad Gallardo Re: LTFT numbers and o2 numbers I have learned the hard way that tuning is very tricky, and it doesn't take much to break things! If I were you, I would consider contacting Predator and finding out if you could get them to dyno tune it for you. I know it would cost some money, but take it from me, it will be nothing compared to the cost of a motor!
If you restored the original tuning, you should be alright for easy part throttle driving.
I know some people have taken their cars to Predator and had Predator dyno the car and set it up with a great tune. At least then, you have a good baseline for them to tweak if you do more mods later.
I have had the problems with the error on the screen before trying to load a program also - I just back out and try again - it will eventually go through.
I had trouble getting my PC to load files to the Predator also. Had to set up my BIOS correctly for the port to work.
At least call Predator and find out where you could take it and what it would cost - I'm telling you, if you don't know exactly what you are doing, you can trash an engine in a very short time. Then you'll look like me
If you restored the original tuning, you should be alright for easy part throttle driving.
I know some people have taken their cars to Predator and had Predator dyno the car and set it up with a great tune. At least then, you have a good baseline for them to tweak if you do more mods later.
I have had the problems with the error on the screen before trying to load a program also - I just back out and try again - it will eventually go through.
I had trouble getting my PC to load files to the Predator also. Had to set up my BIOS correctly for the port to work.
At least call Predator and find out where you could take it and what it would cost - I'm telling you, if you don't know exactly what you are doing, you can trash an engine in a very short time. Then you'll look like me
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers i was told that as long as i dont touch their tune then it should be fine i just need to let them know how to adjust it better for me. i mean my motor runs nice and smooth and the o2 numbers are right on the money every WOT run i make. and they told me theLTFT is the computer compensating to make it run right so it wont mess up. is this true?
TECH Apprentice
Joined: Dec 2001
Posts: 357
Likes: 0
From: Whitby Ont Canada
Re: LTFT numbers and o2 numbers
i was told that as long as i dont touch their tune then it should be fine i just need to let them know how to adjust it better for me. i mean my motor runs nice and smooth and the o2 numbers are right on the money every WOT run i make. and they told me theLTFT is the computer compensating to make it run right so it wont mess up. is this true?
.... so when you get your LTFTs to 0 your O2 readings may no longer be at .900 but at least you will have a stable environment to work from Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers well i put my stock MAF back in until i can find someone to help me out on that. the numbers are around 3 and frequently hop down to 0 so i guess thats pretty good lol o2 is about 890 or so too. i am getting a little bit on KR when i got on it in 4th at 70 is this alright or no? and will i ever beable to get my SLP MAF back on my car without any problems? do i just need a better tune or should i just wait until i dyno tune?
TECH Apprentice
Joined: Dec 2001
Posts: 357
Likes: 0
From: Whitby Ont Canada
Re: LTFT numbers and o2 numbers
well i put my stock MAF back in until i can find someone to help me out on that. the numbers are around 3 and frequently hop down to 0 so i guess thats pretty good lol o2 is about 890 or so too. i am getting a little bit on KR when i got on it in 4th at 70 is this alright or no? and will i ever beable to get my SLP MAF back on my car without any problems? do i just need a better tune or should i just wait until i dyno tune?
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers i talked to someone and they said my car was pinging. it makes that noise at about 5000 rpm. said its signs of detonation. what exactly does that mean? and how can i get it to stop. should i just take the SLP MAF off and the program out until i can get the tune just right? i dont wanna break anything. i was pinging wiht the SLP MAF on there too.
TECH Apprentice
Joined: Dec 2001
Posts: 357
Likes: 0
From: Whitby Ont Canada
Re: LTFT numbers and o2 numbers
i talked to someone and they said my car was pinging. it makes that noise at about 5000 rpm. said its signs of detonation. what exactly does that mean? and how can i get it to stop. should i just take the SLP MAF off and the program out until i can get the tune just right? i dont wanna break anything. i was pinging wiht the SLP MAF on there too.
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers thanks man. i just took it all out and back to stock for now until i can hit up a dyno and get it all right. is that a good idea? lol
Thread Starter
Joined: Mar 2003
Posts: 8,319
Likes: 1
From: North Carolina
Re: LTFT numbers and o2 numbers thanks man. i just took it all out and back to stock for now until i can hit up a dyno and get it all right. is that a good idea? lol i mean with it all stock my fuel trims are hovering at 0
