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s300 misfire

Posted: Wed Sep 26, 2007 7:23 am
by turbotypeR
my car has developed a missfire that i can't seem to figure out. well, i gues it is a missfire. it will rev to about 8000rpm or so and just sit there.it is almost like it looses timing but with a timing light it is around 28 deg when it is doing it, which is right about where the timing map is. here is the calibration and a datalog of me revving it in neutral:

Posted: Wed Sep 26, 2007 9:44 am
by turbotypeR
i took it up the street and it went all the way to 10000rpm but it wasn't as strong as usual. i think it is just rich up there, but i am not sure. i have the plx wideband hooked to it, but i didn't think it was calibrated right. when ths happens,it goes from 12.2 to 10.86 and just stays there, like that is as low as it will read. i am going to post the datlog from the street run in a few minutes

Posted: Wed Sep 26, 2007 9:55 am
by Spunkster
Has the car been tuned on the dyno?

Posted: Wed Sep 26, 2007 10:17 am
by turbotypeR
yes, it has been doing fine. the problem started soon after i changed my crappy aem fuel filter to a good weldon one.i think it is just going rich up there. i guess i am going to have to go back to the dyno and trim some fuel out

Posted: Thu Sep 27, 2007 4:41 pm
by turbotypeR
yup. it was rich. i changed back to the old filter for now and it is back to it's rowdy old self