[pete95t]

i have an 04 9-5 aero

it has a open air intake
3" turbo back exhaust
3.5 bar fpr
and stage 3 nordic

im not sure if i have a bad o2 sensor or fuel pump problems or what but this is what Ive experienced so far..... a few times upon acceleration it has jumped/coughed, it seems to be getting the right boost pressure for what the software requires (20-22) if that seems right ?. the boost tapers off almost like heat soak even if i haven't done multiple pulls. but my main concern is the air/fuel gauge, at WOT it will go straight to rich as it should but anywhere from 3000rpm on the gauge will shoot straight into lean and jump back to rich witch scares the **** out of me so im parking it until i take some steps on figuring out this problem. i've resently put in a new BPC, NGK Plugs gaped to 0.9, cleaned the MAF and thats only 6 months old.

any suggestions ???

 

[ivanwakeup]

clean throttle body, new vacuum lines if yours are old.....how recent is your fuel filter?

these can contribute to "lean status". if your o2 was bad i would think it would throw a code. take a look at your spark plugs and if they look kind of a whiteish-gold-pale, then thats a pretty good indication you're lean, if you have any doubts about the gauge that is.

 

[zingZACH]

i have an 04 9-5 aero

it has a open air intake
3" turbo back exhaust
3.5 bar fpr
and stage 3 nordic

im not sure if i have a bad o2 sensor or fuel pump problems or what but this is what Ive experienced so far..... a few times upon acceleration it has jumped/coughed, it seems to be getting the right boost pressure for what the software requires (20-22) if that seems right ?. the boost tapers off almost like heat soak even if i haven't done multiple pulls. but my main concern is the air/fuel gauge, at WOT it will go straight to rich as it should but anywhere from 3000rpm on the gauge will shoot straight into lean and jump back to rich witch scares the **** out of me so im parking it until i take some steps on figuring out this problem. i've resently put in a new BPC, NGK Plugs gaped to 0.9, cleaned the MAF and thats only 6 months old.

any suggestions ???

The a/f ratio gauge /o2 sensors will "hunt" when not on the throttle... It will vary from lean to rich. As long as it's in stoich or rich when under boost, you should be fine.

Narrowband a/f gauges aren't very accurate anyways... if you're real concerned about it, go with a wideband.

 

[pete95t]

the fuel filter has about 60k on it changing that out was my next step. i will try cleaning out the throttle body next. and its def running lean no dout in my mind the gauge is right into lean and it doesn't run right. my vac lines are a year old i think im gonna replace them again just for the sake of argument

thanks