Should my LTFT be this high?

[Trader]

My long term fuel trims are the following:

idle = 4 to 6
Part throttle = 7.0
Engine breaking = 7.8
Medium throttle & WOT = 10.2

These LTFT are after about 100 miles of driving.

My only mods right now are the MSCAI2 with straighteners.

I have checked all the typical areas for leaks. I tightened up all the intercooler piping and intake piping couplers.

The car does not seem any faster with the intake.

[shadesofgray19]

Those LTFT's are just fine. Ideally you want them to be zero, but aftermarket intakes tend to lean the car out a bit. This is why you are seeing fuel being added. I wouldn't worry about those numbers.

[ZoomMS3]

Originally Posted by shadesofgray19 Those LTFT's are just fine. Ideally you want them to be zero, but aftermarket intakes tend to lean the car out a bit. This is why you are seeing fuel being added. I wouldn't worry about those numbers.

I would be.. You LTFT should be NO higher than 5% at WOT and really shouldnt be any bit higher than 3. Good thing is that a protune will do great things to your setup and you shouldnt cause too much harm with how it is currently running.

[frito]

Did you drive very easy for a prolonged time?

[Trader]

Yes for about 100 miles

[MS6_Auburn_Fan]

Are these LTFTs positive or negative?

One other thing to check is how far the intake pipe goes into the filter. If it goes to far then it can effect everything from fuel to boost.

[Trader]

Originally Posted by MS6_Auburn_Fan Are these LTFTs positive or negative? One other thing to check is how far the intake pipe goes into the filter. If it goes to far then it can effect everything from fuel to boost.

These are positive

[jayspeed3]

From what I have read anything between +-(6%~8%) is reasonable. Zero, or close to it, is ideal.

[bnoon]

Originally Posted by jayspeed3 From what I have read anything between +-(6%~8%) is reasonable. Zero, or close to it, is ideal.

Agreed. If they go higher than 15 (I believe that's it) you get a MIL/CEL if it's sustained for a period of time.

[FCmaniac]

I wish my LTFT's were that low

[Trader]

Originally Posted by FCmaniac I wish my LTFT's were that low

What intake do you have? How high are yours at WOT

[FCmaniac]

Originally Posted by Trader What intake do you have? How high are yours at WOT

I have a Cobb SRI and Cobb inlet. It's only been a couple hundred miles since my last ECU reset so maybe they will come down a bit.

+9.0% at idle
+14.0% at WOT

[bnoon]

Originally Posted by FCmaniac I have a Cobb SRI and Cobb inlet. It's only been a couple hundred miles since my last ECU reset so maybe they will come down a bit. +9.0% at idle +14.0% at WOT

Wow that's high. You checked for leaks?

[Deadman]

mine is 17% at idle, and WOT -1% lol. i wonder if i have a leak..

[FCmaniac]

yes I've checked for leaks. I can't find any. Everything is tight and installed correctly. I had even higher readings when I had just the Cobb SRI... I'm not the only one either.

[FCmaniac]

Well my LTFT's came down today finally... 5.5% at idle and 7.8% at WOT. All I did was beat the crap out of the car. I've been driving like an old man for the most part for the past couple hundred since the ECU reset for inlet install. Today I decided to do a few WOT runs. What also is interesting is that I got some mild KR in the upper RPM's the first couple times and then it went away and kept feeling better. I think the ECU just gets used to how you drive and maybe doesn't react to changes as quickly as we think.

[08.5TRS3]

yea my ltft are around 15 but ive been drivin like an old lady for a few months maybe ill beat the shit outta it for a few days and see what happens lol

[08.5TRS3]

i jus checked mine out and my shits all over the place lol at idle its 19.5, if i barely touch the gas like 100 200 rpms tops its 14.3 and if i do jus a hair over that like maybe 1/8 throttle its 8.6 lol why the hell is it all over the place like that within that little bit of a change of rpm

[AndyMS3]

Originally Posted by Deadman mine is 17% at idle, and WOT -1% lol. i wonder if i have a leak..

Originally Posted by 08.5TRS3 i jus checked mine out and my shits all over the place lol at idle its 19.5, if i barely touch the gas like 100 200 rpms tops its 14.3 and if i do jus a hair over that like maybe 1/8 throttle its 8.6 lol why the hell is it all over the place like that within that little bit of a change of rpm

Sounds like you guys gots leaks.
I would inspect all hose connections thoroughly.

[DaleNixon]

The OP has fuel trims I dream about!

I might have a leak, but I've checked every hose I can find.

[ThEsHoCkEr]

I'm getting some high LTFT also. Here is my thread

http://www.mazdaspeedforum.org/forum/foru...og-inside.html

Not sure what's causing it though.

Edit: I also have been driving like a granny the past 200 miles to let my ECU relearn this new map. I don't know if that's a factor or not though.

[08.5TRS3]

i checked for leaks didnt come across anything boost leak tested it and retighten everything ... if i gotta leak it cant be much of one because my car is still runnin like a champ .. i donno this cars anal

[DaleNixon]

I did some WOT runs the other day for a thread on this forum and my trims have suddenly gotten a lot better. It might have to do with the warmer weather we've been getting. Or maybe I just needed to blow the carbon out of this mother fucker

[frito]

That is good to hear.

[DaleNixon]

Update. My trims are staring to move to relatively sane levels! It's great. I recently installed an ETS 3.25" TMIC, Denso ITV22 step colder plugs, and added two shims to the blue spring on my Forge valve.

I did some WOT logs (starting in 4th gear at 3000rpm) to show someone in another thread, and I noticed my LTFT's starting looking a lot better!

At this point I'm idling no higher than +3.9, Cruise is around +3.1, Moderate gas puts it around +5.8, and hard throttle/WOT puts it around +11 to +13.

These trims aren't perfect, but they're a hell of a lot better than what I had. I'm not sure if my recent mods helped or just the warmer weather I've been driving in, but I'm one happy camper right now! My knock retard warning on the DH has been missing in action as well! (knocks on wood)