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Discussion Starter #1
My plugs are whitish colored - which is lean - and my o2 sensors have a whitish color to them now. My a/f at full throttle goes from 11:1 while it spools - to7.8:1 which is pig rich at full spool. I'm lost? any ideas?
 

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Are you using a wideband? I would say get it calibrated, I had the same problem when I put my new Innovative wideband on, then I calibrated it and its ok now. Also what is the reading at Idle?

Lawrence
 

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What is your set up.(eng, fuel etc..)? the reason I ask is mine says 14.7-15 at idle and normal driving. If your afr is fluctuating that much sounds like an vacume leak. The idle must be all over the place.

Lawrence
 

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Discussion Starter #5
the idle is fine and vacuum is excellent. VQ30DE motor - 555cc injectors, aem fpr, cartech fmu, walbro 255lph pump.
 

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What kind of vehicle is this? Vq30 or VG30? dont remember vq30 only vq35. Just an guess but maybe if you are running too big of injectors and too high fuel pressure will lead to low afr's. I would try to drop the fuel pressure a bit and see if it changes.

Lawrence
 

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Discussion Starter #7
VQ30DE was the precursor to the VQ35, I know I'm burning rich - but I'm afraid to lean it out because of the white plugs - I know my turbo was leaking oil into the intake pathway - would that make the plug turn white?...
 

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Discussion Starter #8
Also, my o2 sensors - which NA where typically the coppery brown color - have become white colored - not really encrusted or anything - just white.
 

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what kind of fuel are you using? if you are on leaded race fuel then it may turn white from that. at least mine always do. Burnt oil is usually dark to my knowlege.

Lawrence
 

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What is your Static Fuel Pressure? Where is the sensor mounted? I would suggest doing a pull and then killing the motor and pulling a plug right away as the motor may a lean spot just around idle and if you do a pull then let it come down to an idle and idle it will clean the carbon right of the plugs. What is white the insulator? no hint of brown, can you see how far the heat soaked up the threads if so count how many threads it climbed up.
 

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Discussion Starter #12
static as in at idle? if so, 32 psi of fuel. The sensor for the wideband is about a foot past the turbo in the downpipe. The insulator wasn't really white, it had dark deposits on it - the electrode looked fine, it was the strap that was white colored - and yeah, i'll try killing the motor... only thing is- with the turbo being that hot after a run - don't i need to worry about oil starting to choke up the turbo?...
 
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