Thread: Running Lean

Hey guys,

Had some questions for you. My car used to sit at -7.0 ltft at idle no matter what for a long time. Recently my intake has fallen off a couple times which would cause the car to run really lean. Once I put the intake on again, it would go back to normal. Now with the intake fully on, the cars idle has been extremely lean. 24.2. No codes, sprayed the vacuum lines with carb cleaner and no changes. The car runs okay but I can tell its not like it used too. Sometimes i'll feel a sputter under ~50% throttle. I'll also have a hard time sitting at stop lights sometimes where the revs will drop real low and try and bounce back and shake. It'll then straighten itself out and work better. I also tried changing the MAF with another one I had laying around. Any ideas? I have plans to go to the dragstrip in a week so I would love to get this thing running again.


Chris

sounds like a vac leak. spray the tb gasket, injectors lim and blower gaskets, move the vac lines while you spray em.

do this car running of course.

I've sprayed and haven't gotten anything. I'll keep trying tho. I was going to replace the plugs too before I went cuz idk how much is on them

egr tube too if you got one still. they split.

Where it goes into the LIM?

yup, theres a seam on it.

I kinda sprayed around and didn't find anything. I'll have to get more carb cleaner. My idle used to be at -7.0 for awhile. In park, when I hit the gas my trims will go way lean. Then slowly creep back to -7.0.

whats your ltft wot? i fits just lean at idle id not care really, its hot out now and if this is your first summer with the tune things can change a bit due to the seasons.

But i still feel that little shutter and the thing will surge when i pull up to a stop light. i haven't done a wot run yet cuz idk how it'd react. it'll idle good now but when i blip the throttle in go real lean.

if i just rev the engine a few times my wb reads lean. could be normal if its on the rpm drop it reads lean.

how old are your plugs? they only last 12 to 15,000 miles.

I have new ones getting ready to be changed. At idle the boost on my aero force reads 19.3 to 18.7 and sometimes a little lower. Fluctuating every second or so maybe.

Lower as in 18 or so.

thats basically vacuum out of boost.

So that's normal?

i dont have a fancy gauge like that so im not familiar with it at all, but dhp scans show neg boost at idle, about -10. its reading the map sensor.

negative boost doesnt exist idiots, its "inHG"

- fuel trims you are running rich, I cant tell if your rich or lean -7 rich, 7 lean.

My aero at idle reads up to 22inhg, my inhg/boost gauge about 18

I never logged "boost" on my aeroforce because the MAP in/hgs is far more accurate. We have a 2 bar MAP sensor so it will read boost pressure with that pid.

Car had a little pause every time I accelerated from a stop. Did it maybe 10 times. I unplugged the maf and drove it around. Didn't do the pause once.