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LTFT pegged at 16.4



If it's before the first o2 sensor it will. I was leaking right at the collectors on my front header, left me at 16.4 all the time. Fixed the leak, back down around +5
 


Evap opened , has a leak. Goes away when closed. Just a thought.
While its running, pull the line going to the solenoid and see if the solenoid is sucking air. If it is, it's open. Plug the line going back to the motor and see in real time the trims settle
 
crazyguy03 said:
Evap opened , has a leak. Goes away when closed. Just a thought.
While its running, pull the line going to the solenoid and see if the solenoid is sucking air. If it is, it's open. Plug the line going back to the motor and see in real time the trims settle
Click to expand...

i recently deleted the evap system and plugged the tb vac nipple, i deleted it trying to fix my fuel trim. no dice..

replaced my vac lines to boost solenoids, they are all new, new t's and lines.

i had to take apart the top end for a rebuild, new gaskets everything.


also why would a exhaust leak give negative fuel trim?? anything under 0 is leaning out your afr. if you have a exhaust leak, it reads extra oxygen, at that point it would add fuel, not take it away.
 


open loop.

hope your fuel/air models are accurate unless you like carrying your tuning software around with you.
 
i dont have any tuning software at the moment, and having a hard time getting zzp to get back to me about what the commanded afr is and if i could run in open loop.

i asked my instructor about it as well, he said i could if i was tuned for it, but being its a canned tune, not a good idea.


i did a WOT 1 and 2nd gear pull and i got 6.6lbs of boost. is that a normal number for my flow mods with a 3.5 pulley? if its normal, then it cant be a vacuum leak. one large enough to peg my LTFT would drop my boost, yes?
 
i havent had any problems running NIC stuff on a stock tune. what does the wideband say / what are the LTFTs at cruising/wot?
 
dont have access to scanner at the moment, but did find something interesting, when i move my egr valve, you hear a sucking sound...

so now i have to source a new egr valve, i dont want to delete it and then start knocking bc of higher cylinder temps. i definitely smell heavy exhaust fumes around that area, but could be coming up from under the car where my large exhaust leak is.
 


"move" your egr? as in the tubes going to the intake and the exhaust?

If you can delete the EGR, it will only help you. Only thing it does is improve emissions at cruise, maybe.
 
crazyguy03 said:
Question. How does deleting hot exhaust fumes from entering your intake manifold RAISE cylinder temps?
Click to expand...

The EGR recirculates spent exhaust gases back into the combustion chamber. Being that there is little to no oxygen content in the exhaust stream, all that's really there is some unburned fuel. The fuel can only mix with the oxygen brought in during the intake stroke. Thus, since there is no oxygen, there is less burn and lower combustion temps during cruise.
 
crazyguy03 said:
Question. How does deleting hot exhaust fumes from entering your intake manifold RAISE cylinder temps?
Click to expand...

It doesn't.

It REMOVES hot air from the intake side LOWERING intake temps and killing the carbon build-up that always is associated with EGR. People claim EGR hurts MPG's...I never saw a loss in MPG's, people just like to b1tch.

There's your problem and your vacuum leak. Just block it off with two pennies and some RTV so you don't have to worry about it again.
 
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