thatsallfolks

Yes, they said it was the A/F ratio sensor. No, the engine malfunction light was not lit. But it was lit when this whole thing started last spring. So back in June, based on the engine error code, they replaced the rear O2 sensor. I wonder why they never considered replacing the front one (I assume that's aka the A/F ratio sensor), especially when the problems persisted? Anyway I didn't know about the recall. It really did seem like a lot more hassle than it should have been. I can only say I'm glad it's over and the Outback is running well again, and Subaru picked up the tab (of course, if it was a recall item, they would've had no choice anyway). And thanks for all the input.

Well, the dealer finally found the cause; it was the air-fuel mix sensor. Once they replaced that, the car drove like new. I'm pretty confident in the repair at this point because it's been about 3 weeks now, and we've had no sign of the earlier problems reappear. It took the dealer maybe 10 days to actually find the problem; I drove a rental the whole time they had my car. But Subaru paid for everything. Needless to say I'm happy with Subaru and the final outcome. So, if anyone else out there is experiencing similar problems, have the dealer check the air-fuel mix sensor; it just might be the culprit. I hope this experience winds up helping someone else too.

Hey, thanks for the replies. The dealer does have the car now; they're trying to reproduce the problem. Depending on what they come up with, I plan to show them your comments, 9obw. I'll let you know how this plays out. Hopefully it'll have a happy ending.

Hi all. This is my first post, so I'll try not to commit any faux pas. I have a 2000 Outback I bought new. It has the 2.5 liter phase 2 engine with an automatic transmission, and about 49,000 miles on it now. For several months it has been running wrong. Sometimes it hesitates from a stop, or slow start; sometimes it idles rough. But the worst is a bucking/jerking that takes place on deceleration. It happens somewhere between 30 and 40 mph and the tach is around 1500 rpm. Deceleration can mean coming off of a freeway ramp from 70mph, or just slowing from 40-45mph. It's unpredictable, and intermittent. And by bucking/jerking I mean the car will do this until speed drops below 30mph. So it will jerk back and forth maybe 30 times. It is not a one time jerk like a hard downshift. Anyway, I have seen lots of stuff on hesitation and rough idle, but what about this bucking thing? So far, the dealer has replaced the rear O2 sensor, the vent valve by the gas tank, and re-flashed the ECM. As a stab in the dark, they also cleaned the throttle plate. As my own stab in the dark, I replaced the fuel filter and the PCV valve, and tried some fuel system cleaners. Nothing has changed. Has anyone had a similar experience? Has anyone fixed the problem? I'd appreciate any help. Thanks.