O2 sensors frequently need replacing

[ameuse]

I have a 2002 Forester and have had to replace one O2 sensor twice and
the other one 3 times so far. Check engine light just came on again
today and I am dreading having to replace another one (gas cap is
tight so I figure its the O2 yet again)

Anyone know if this is a common problem? I have read about rear wheel
bearings going out, 75k miles and I haven’t had to replace them yet.
Also the clutch shudder problem, which happens to me when its cold out
and the car is cold. Of course people don’t usually post things on the
internet like "my car has been running fine thanks", but this O2
problem is making me think I should trade this thing in before having
to deal with the clutch and the wheel bearings.

 

[Todd H.]

I have a 2002 Forester and have had to replace one O2 sensor twice and
the other one 3 times so far. Check engine light just came on again
today and I am dreading having to replace another one (gas cap is
tight so I figure its the O2 yet again)

Anyone know if this is a common problem? I have read about rear wheel
bearings going out, 75k miles and I haven’t had to replace them yet.
Also the clutch shudder problem, which happens to me when its cold out
and the car is cold. Of course people don’t usually post things on the
internet like "my car has been running fine thanks", but this O2
problem is making me think I should trade this thing in before having
to deal with the clutch and the wheel bearings.

For one, wheel bearings cost very little to replace if you get to them
before they explode.

As for the o2 sensor, I haven't heard it much, but I suspect something
is not quite right in terms of combustion if they keep going bad, or
perhaps the ECU is flagging good ones as bad? I'd have the dealer
dig a little into that.

Depends how much you like the car really, which way to go. Keep in
mind that if it's paid for, the repairs you cite are probably one or
two car payents at most.

Best Regards,

 

[.._..]

O2 sensors do often go. (Mine did in 2004, on a 2001 Outback)

Wether or not that is different than other manufacturers I don't know. It
seems to me like the nature of the device is to go often.

How much are you paying for the replacement? Have you considered doing it
yourself?

 

[Rick Courtright]

I have a 2002 Forester and have had to replace one O2 sensor twice and
the other one 3 times so far. Check engine light just came on again
today and I am dreading having to replace another one (gas cap is
tight so I figure its the O2 yet again)

Hi,

I think the life of O2 sensors SHOULD be at least whatever the Federal
smog equipment warranty life is (used to be 50k miles. I've heard it's
up? Dunno for sure) but most sensors, both OEM and aftermarket, are made
by Bosch or Hitachi AFAIK, and the guys at the auto parts stores tell me
15k-30k is about average for the ones they sell.

Driving conditions may have a lot to do with this: are you out on the
highway all the time (should mean longer life) or stuck in traffic half
your life (which probably halves the life of the sensor, too)?

And, on the ones that WERE replaced, were they OEM "plug-in" units, or
aftermarket "splice the wire to fit" units? I've read that if one cuts
the wire, it's critical the spliced wire matches the length of the
original as close to exactly as possible. (Has to do w/ voltages
available to the ECU from what I've read.) And if you're running "rich"
due to driving conditions, engine conditions or maybe other sensors "on
the edge," I've read your O2 sensor life will be cut dramatically.

Rick

 

[Carl 1 Lucky Texan]

ameuse wrote:




Hi,

I think the life of O2 sensors SHOULD be at least whatever the Federal
smog equipment warranty life is (used to be 50k miles. I've heard it's
up? Dunno for sure) but most sensors, both OEM and aftermarket, are made
by Bosch or Hitachi AFAIK, and the guys at the auto parts stores tell me
15k-30k is about average for the ones they sell.

Driving conditions may have a lot to do with this: are you out on the
highway all the time (should mean longer life) or stuck in traffic half
your life (which probably halves the life of the sensor, too)?

And, on the ones that WERE replaced, were they OEM "plug-in" units, or
aftermarket "splice the wire to fit" units? I've read that if one cuts
the wire, it's critical the spliced wire matches the length of the
original as close to exactly as possible. (Has to do w/ voltages
available to the ECU from what I've read.) And if you're running "rich"
due to driving conditions, engine conditions or maybe other sensors "on
the edge," I've read your O2 sensor life will be cut dramatically.

Rick

I think I'd be concerned about the fuel mixture too. Either that or the
dealership is generating income with you. The next time the light is on
have an Autozone (or different mech.) read the codes. Then, post back
here, we'll help you clear the code, see if it immediately returns, etc.
Also, even after an O2 sensor change, are there any complaints with how
the car starts and runs? Especially when cold and hot.

Also, what is the mileage on the car, have you had it since new, are
there any modifications to it?

Carl

 

[Edward Hayes]

115,000 +miles on my 2000 Forester and never needed to replace an 02
sensor. Ops the recall replaced a good one with a good one at ~ 4,000
miles. Now that I've said it I'll probably need two replaced next
week. ed

 

[CompUser]

And, on the ones that WERE replaced, were they OEM "plug-in" units, or
aftermarket "splice the wire to fit" units? I've read that if one cuts
the wire, it's critical the spliced wire matches the length of the
original as close to exactly as possible. (Has to do w/ voltages
available to the ECU from what I've read.)

While this could be a big issue with RF voltages,
the emissions system (and sensor) would have to
be staggeringly sensitive for a wiring length of
inches difference to make a difference.

Sounds like an old wives tale, probably sales
based.

 

[Steve Parker]

I have a 2002 Forester and have had to replace one O2 sensor twice and
the other one 3 times so far. Check engine light just came on again
today and I am dreading having to replace another one (gas cap is
tight so I figure its the O2 yet again)

Anyone know if this is a common problem? I have read about rear wheel
bearings going out, 75k miles and I haven’t had to replace them yet.
Also the clutch shudder problem, which happens to me when its cold out
and the car is cold. Of course people don’t usually post things on the
internet like "my car has been running fine thanks", but this O2
problem is making me think I should trade this thing in before having
to deal with the clutch and the wheel bearings.

ameuse,
That car should have a 75k miles Federal emissions warranty, O2 sensors
are covered under this warranty. The O2 sensors should last at leastthis
long.
As for the frequency of failure I would suspect contamination from
something in the gas. Do regularly put something in the tank as a cleaner?
Another possibility is there is another component failure causing a
cascade effect that kills the sensor. Does this car have 2 sensors one
before the catalytic converter and one after? Depending on if this is
the case and one or both are failing it might give an indication as to
the real problem. Hope this helps.
Sparky

 

[ameuse]

I got the car new and have only serviced it at the dealer, so whatever
O2 sensors they use are what have been replaced. The car is standard
with no mods. After the sensors are swapped out everything runs fine,
now I take the car in to be checked out when the check engine light is
on more than 2 days. The first time I needed them replaced I couldn’t
get to the dealer for a couple weeks and by the time I got there the
car was practically undrivable.

About 50% of the 75k miles on it are from highway driving.

I never thought about those repairs being small when compared to a car
payment, and I have the car paid off, so thanks that makes me feel
better. So far the O2 sensors have been under warranty. The first 2
replaced extended the warranty for the part and since then when I have
the replaced them the parts have still been under warranty from the
last replacement. I am just afraid it will be a yearly thing now

 

[Edward Hayes]

I think it would be time to have a talk with the Subaru representative
in your area. I say this because what your experiencing is very
unusual and if it continues it will become costly. I would also check
the 02 warranty as some emission parts are warranted for 80,000 miles.
Something is causing the 02 sensors to go bad and Subaru has had bad
batches of 02 sensors in the past or maybe the dealer is not using OEM
parts or ????????? Ed Hayes