anders44

well, borrowed a elmscan odbii, and rand scantool.

car hasn't been running like it should, and there is slight hesitation at midrange often, but from time to time it really misfires/jolts

here is what it showed

soo hmm test new sparkplugs, but likely all coils are goners or what usually causes this on 911/boxsters?

anders44

I've been searching, this is actually get car,
http://www.renntech.org/forums/index...19647&hl=p0300
as suggested here, is o2 likely?

Macster

any anomalous voltage readings.

Could be O2 sensor.

What are long term fuel trims? (You need to note these *before* you clear DTC and extinquish MIL. Long term fuel trims are reset to 0 upon error code erase, along with readiness continuous monitor results.)

Could be low fuel pressure on one cylinder bank.

Could be (not that up on Boxster engine igntion) if there is a separate connection to a cylinder bank and its population of coils/spark plugs could be this connection is marginal.

Fill up with E85 by mistake? (Or diesel?).

Could even be failing AOS (air/oil separator). It connects to intake manifold on the bank 1 side -- just downstream of throttle body -- and could affect one cylinder bank before/more than the other.

Sincerely,

Macster.

anders44

I'm gonna try swapping o2 sensors first, also got 6 new plugs. new AOS has been orderd as well.

codes are reset, talk about huge difference in midrange.

it's been getting the correct fuel.