Lean Idle

[4g63owns]

I just got my wideband installed yesterday. i put the new bung in about 36 inches from the manifold like it says to in the instructions. Im putting in +26 on my neo at 1000, and then about +10 at 2000. After that there all a little over O. im just wondering if my wideband is supposed to be running about 17.5? that seems a little lean to me. also, does anyboy have any suggestions for a logger for my '96? ive been looking, but im ot sure what one is best for the '96. any body got any suggestions? thanks

 

[talonDSMerr]

Your wideband should ideally read around 14.7 at idle. A vacuum leak after the maf sensor will cause you to run lean at idle. Do a boost leak test and find out if this might be the culprit.

 

[steve]

Is your Neo a fixed one? They have a know problem with Karman sensors that only was fixed a little while ago.

Do you still have a narrowband sensor in the O2 housing for the ECU feedback?

 

[zhjiln]

maybe leaky flex section on downpipe.....

 

[IceMinion]

I am not sure, but my narrowband always, always reads way lean at idle, and as far as I know, this is normal.

People worry about running lean, but what people do not know is the only time that running lean can damage the engine is when your car is actually generating horsepower.

You can lean-burn your car on the freeway, some people go up to 17:1 (using e85) and 16:1 (using good 92) this will not destroy the engine (arguably) because the total fuel involved is insufficient to melt aluminum.

However, lean-burning under boost will result in knock, melted pistons and ruined valve seats.

so lean during idle = no worries!

 

[324vr4]

Good to know ^^^^ I am experiencing the same at idle and under loads it changes but all I did for more "comfort" is crank the AFPR psi higher by 2 psi...seems to be more level but still shows lean at idle...i don't think you have much to worry about tho if that's where it's at under idle...if it doesn't change under load/WOT you need to fix that before you need a motor...just keep an eye on your AFR gauge while cruising and make the call...

 

[4g63owns]

now that i think of it, theres a small sensor that has a vacum line leading to it right in fromt of the driver in the engine compartment, and i broke the little nipple off that is supposed to have a rectangular cap on it. I meant to get a new one, because it broke off when i had to drill a hole in the fire wall. And yes i am running ok during boost and cruising, its just that im kind of picky about my car and i dont want anything to happen to her Also, im running high octane(91 or 93, not sure in wisconsin) so i dont know if that has anything to do with a little lean. Thanks for the help, much appreciated.