Lean condition all the sudden

[hardcorandy]

Starting to get a little worried about my A/F reading of 12.5 @14psi WOT. As of a few days ago it was more like 11.5 which im fine with. Ive done a BLT and found one small leak that has been fixed. Ive also reset the ECU which has worked in the past. Seems like when i go WOT the A/F will drop to 11.3 the lean out right away. I do have a boost creep issue but this is all "pre creep". Ive then tried running waste gate pressure and come up with A/F of 12ish. Ive pulled my plugs to see if my wideband was lying and its not.

The only thing im coming up with in my head is I have run my tank low the other day to the point that Ive had to put 11 gallons back in it. Which is the lowest its ever been. Fuel filter has 18k on it and is a purelator. I listened to the fuel pump at idle closely and it has constant high pitch signal sound but then you can hear the pump kick on and off. Is this normal?

Now as far as my boost creep, It seemed like when i went and messed with my boost controller its creeping at a much lower rpm now. Outside temperature has dropped to 65* the past few days. Does any sort of temp have anything to do with creep? Like it used to not creep till about 5500. Now it seems like 4500.

My car just acts so random sometimes and it drives me nuts. I read allot of threads on here to study and soak up everything i can. I need a little advise please.

 

[DSMReviver]

you are running rich, not lean. 12:1 is your target air fuel ratio in turbo cars.

http://www.bristoldyno.com/tech/airfuel.htm

 

[hardcorandy]

11.1 would be a perfect world on pump gas. 12.1 is lean for a turbo car. My plugs are white at a 12.5. I dont get how thats rich. 12.1 may be rich for a n/a but no for forced.

edit: I see where you are coming from. Ive read the article. But if a 12:1 is rich then why are my plugs completely white at 12.5:1? Ive just read on here that 11:1 was target. My car seems much happier on a 11.5:1 then a 11:1 though.

 

[DSMReviver]

It depends on what part is white. if the insulator in the spark plug is grayish white or grayish yellow to brown this indicates the engine is operating in normal conditions. Look at this article, specifically figure one and two, if thats what it looks like its normal. If it doesn't look like that look further down and see if you can match to one of those pictures.

Spark Plugs and Spark Plug Wires - Facts & Repair Advice

 

[hardcorandy]

Plugs look like figure 1. I have just always though it was supposed to be more like a nice golden brown.

So thats one problem down. Now i need to figure why touching my controller and/or weather changing made my boost creep worse. I understand the whole 14b wastegate issue and know it needs ported. Im biding my time with this turbo as its gonna get changed soon. I had the creep controlled for the most part this summer.

Thanks for your help though man.

 

[Boosted98gsx]

11.1 would be a perfect world on pump gas. 12.1 is lean for a turbo car. My plugs are white at a 12.5. I dont get how thats rich. 12.1 may be rich for a n/a but no for forced.

edit: I see where you are coming from. Ive read the article. But if a 12:1 is rich then why are my plugs completely white at 12.5:1? Ive just read on here that 11:1 was target. My car seems much happier on a 11.5:1 then a 11:1 though.

NO! 11:1 is rich enough to cause damage to your turbine under full load for prolonged periods of time (too hot). 12:1 is the ideal air/fuel ratio for a turbocharged vehicle.


I would check your fuel filter(s)

 

[hardcorandy]

Good thing i was never able to get it down to 11:1 then. Makes me feel much better. Ill get on the filter tonight as well. I always upkeep as much as possible. Ive been thankful to have a reliable dsm because of it.