I have the name of the prev. owner, and the dealer (just met with the dealership owner) invited me to contact him. He swears up and down that the car had no pre-existing issues... But I'll call tonite or tomorrow to see.

I'm gonna unplug the battery tonight to see if it runs well for a time after, as well. This because after getting it back from the mech two weeks ago, the car behaved well for a time before going back to old ways.... Thought being that if an O2 sensor (for instance) is giving "valid but wrong" values, the computer may be trying to tune towards an incorrect target. It costs nothing to try.

Dealer is still insisting it must be fuel related. I'm not so certain. I've had 2 tanks thru since last service, with the problem continuing. I've been adding isopropanol to deal with any remaining water.

Anyhoo, back to "wait'n'see" mode, with some experimentation....

J

When someone mentioned possible o2 sensor and I believe you said this one had 100,000kms on it..dont you think that given the mileage it may be long in the tooth and suspect???? I also beleive you said the plugs had close to 100K on them..I know the manufacturer says that is within parameters, but maybe possible that there is a bag plug in there

This may be completely off base but could back pressure cause the kind of miss you're describing? I've heard of similar cases involving a broken baffle within the muffler that would temporarily move or shift as a result of throttle position / vehicle orientation / load and cause enough back pressure to force the engine to hesitate. Maybe this is a condition that would result in a code but, if not, it could be a piece of the puzzle.

I did unplug the battery over the weekend, and while the car doesn't work perfectly this morning (didn't drive anywhere all weekend!), it is markedly improved. I do believe that the O2 sensor will be at least a part of the equation. This morning's drive didn't feature any "bucking" or "missing like symptoms", but rather hesitation and lagginess (failing to respond to throttle), followed by a burst of power. Other times, it worked politely.

Shooter, I've had a baffle loose in a muffler before ('86 Celica GT, my first car!), it causes really.... Interesting.... Symptoms, but it's not the cause here. Sadly.

Will advise.

J

Jason.

Aint totally up to speed w/your fun(grin), but did they clean the entire tank and/or fuel system? If they found crud in the tank, unless they removed, cleaned, reinstalled, I suspect gas.
Im not saying it aint something else, but I've dealt w/stuff in the tank, and sometimes its not fun to get clean.

HTH..good luck...notnew....

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How's your gas mileage.....

Not realyy a good question, since you don't have
a lot of history.

Is the exhaust pipe loaded with soot?

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Gas mileage is decent, about 600km to the tank, similar to what my Camry has gotten the last many years.

Tailpipe is normal, no excess carbon.

My impression is that the engine tends towards lean, not rich.

J

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It's time for a .... WHASSUP????

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Indeed it is!

Car went in to Subaru yesterday, they checked all that they wanted to check and then hooked up to diagnostic machine.

Front O2 sensor reading incorrectly. Replaced. Car drives normally. Has clean bill of health now.

Jason sleeps better.

Thanks for your input, guys!

J

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....I'll be watching

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