Car running lean until boost.

[redliner_x]

My car will run lean until it hits boost. When you start it it run 21.9:1 on the wideband and has 10hg of vacuum. If you let it run for a few minutes it will idle up and have the proper vacuum.

While driving it will run lean until it hits boost. For instance it will run 18:1 during cruise but if you go into boost it will kick down to 11:1 instantly and get all of the power back. You can feel it pull time until it makes boost then it feels good.

There are no vac leaks but it idles high, at like 2000-2500. I smelled raw fuel earlier so I was thinking I may have a leaking injector o-ring. I am really not sure what to think about it. There is a video below of me driving earlier today.

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[redliner_x]

No one has had this problem or has any advise?

 

[Melbowski]

You're absolutely sure there's no vacuum leaks? That's sure what it sounds like: lean under vacuum, rich under boost, jacked up idle. Reset your base idle first off, that's a lot of air going around the BISS to idle at 2k. Check your IAC, make sure it's functioning properly (ohm it out, check its movement). Any exhaust leaks before the wideband? Where is your wideband installed at? Most people tend to install them after the flex-pipe, which are prone to leaking and will make your wideband read lean at idle as it pulls air into the exhaust, but under boost there's so much exhaust gas rolling through that it reads about normal.

Check into that and let us know.

 

[crazyquik22023]

2000-2500 is very high for idle. As stated above check your ISC. Here are some good videos to show you how to do it. http://www.dsmtuners.com/forums/articles-tuning-ecu/386663-dsm-isc-motor-testing-replacement.html Make sure your BISS screw is set correctly. But it sort of sounds to me like you are having a problem when your car is in closed loop. When you are at WOT your car goes into open loop and uses maps for fuel control, when you are cruising your ECU controls fuel by the o2 sensors and MAF. You may have a bad front o2 sensor or a dirty/bad MAF sensor. Clean your MAF and check and replace your o2 sensor.