why am i still running lean?

ok, so i just did a aod to t-5 swap and let me tell u that i wish i had a t-5 in the first place. anyway, i used to hear popping with the aod and i thought it was the tranmission but it still hesitates and pops with the t-5 so i asked my friend/mechanic what it is and he said its misfire from running too lean. So i replaced the MAF sensor and that hasnt cured the problem. i also found out my exhaust towards the back was rubbing against the fuel line and i actually had to replace that and that made it run better. BUT like i said, it still pops and hesitates. Any other ideas? what can i do? thanks a lot guys!
 
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Pull the code's. the code readers 29 bucks at walmart. Since your lean look at fuel delivery. Fuel pump/injectors fuel filter. Are you sure your not gett'n detonation? check the timing.

Since you said your exaust damaged your fuel line i suspect fuel filter but its hard to tell.

I think the computer may also lean out the mixture if you have a bad or faulty o2 sensors? But thats where pull'n the codes comes in.
 
thank you for the help bramm, woulda never thought of those things! i did recently (very) replace the fuel filter....and when the t-5 swap was done my mechanic/friend said he ran a fuel-system cleaner to clean the injectors....anyway i will get that code puller (thanx for the tip) from wal-mart and pull the codes..... and i will ask about the injectors and the fuel pump.... (ask my mechanic what he thinks)...something else that might have something to do with this...let me tell u...is that when the engine is cold and i just start it up and it is in neutral or in 1st for that matter... and i push on the gas...the car tries to DIE...i dont understand why...its like the engine is having trouble connecting to the tranmission (also had this problem with the AOD).....
 
or at least thats what it feels like...so when i try and push the gas a little the cars RPM's actually drop!!!! wtf?!? anyway....the problem goes away after the car is warm, but it still.... i dont know what could cause that?
but when u get past that "certain point" and u push the gas pedal a little more to try and rev it to like 2000 it jumps up and doesnt try to DIE anymore!!!

all i have to say is

??????????????????????

someone please help me figure this out. i wanna go on a road trip to CA later this summer.
 
If the O2 sensors are bad or the readings stop, the ecu drops into open loop mode - the same mode it's in during a cold start. In open loop the system runs richer, not leaner. It won't pull fuel to run leaner unless it has reliable O2 readings.
 
See my message again - no, the computer DOES NOT lean out the mixture if you have bad O2's or a faulty signal from them; it goes the opposite way, into open loop where it makes it richer.

But you are correct - quit guessing at it, and pull the codes first. That's always the first place to start.
 
yea, i couldnt remember if a faulty o2 sensor leaned out or richened up the mixture. Just a stab at possably somewhere to look. The code reader's worth the cash to have in your toolbox as long as you dont loose the manual with all the code definitions in it.
 
sounds like a dead spot in the tps, you can check this with a volt meter. or unplug it, and drive it see if it still has the same symptoms. you will need to reset the ecm after you drive it so the tps code isnt stored. hope this helps.