2001 A6 2.8 Exhaust pipe and O2 sensor questions.
#1
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2001 A6 2.8 Exhaust pipe and O2 sensor questions.
OK, the driver's side flex joint is blown, the passenger side is not far behind. The local shop wants ~$450 to fix. Says he needs to drop the pipe to weld in new flex. Anyway, now the resonator pipe has disconnected from the hangers, I had to use a strap and some wire to support. To top this all off it looks like I need 2 new sensors B1S1 and B2S2 are throwing error codes, AND I am getting code P0420, catalytic efficiency below threshold. The car has 200K on the clock. What are my options here??
A new resonator pipe is ~$250 to $300, which I can install. The two front catalytic pipes are expensive, it's a NY/CA car. The mufflers look ok, for now.
So.... Do I change the two O2 sensors that have codes and see what changes? My fear is I will spend the money to fix the flex joints, only to have the cat efficiency code come up on both sides, then what? I can't see spending over $1,000 for two cat pipes on a car with 200k miles. Can I install the 48 state pipes? I can get those much cheaper. Will the engine light come on, does the ECU care which pipes are installed?
Codes that were pulled
P0135
P0420
P0159
P1177
P0156
Thanks
Rusty
A new resonator pipe is ~$250 to $300, which I can install. The two front catalytic pipes are expensive, it's a NY/CA car. The mufflers look ok, for now.
So.... Do I change the two O2 sensors that have codes and see what changes? My fear is I will spend the money to fix the flex joints, only to have the cat efficiency code come up on both sides, then what? I can't see spending over $1,000 for two cat pipes on a car with 200k miles. Can I install the 48 state pipes? I can get those much cheaper. Will the engine light come on, does the ECU care which pipes are installed?
Codes that were pulled
P0135
P0420
P0159
P1177
P0156
Thanks
Rusty
#2
AudiWorld Super User
a lot may depend on your states emissions requirements.
I am not sure I would invest too much either on a car with that much mileage.
a good ( trusted ) muffler shop should be able to weld in those flexes for less than that . I dropped my pipes ( disconnected at the head ) gave me about the extra inches I need but the trick is lineing up the parts correctly so the cat is square when you weld her up ( I had a buddy do it ) .
generic O2 sensors ( bosch ) can be has aftermarket and spliced in . I found that cheap and easy . You could look at a wreckers for the exhaust pieces you need and clamp them in , that might get you by ...
BUT ... it is all too common to shoot the messenger .. by that I mean your o2 sensors are telling you you have a cat issue , .. I would fix the flex issue first as you are upsetting the chemistry upstream of the S2 sensor.
I think vag com can actually report the efficiency of the o2 sensor and tell you if its getting old, I seem to remember doing that .. At 200K tho ... maybe time to look at a less "exhaustive" car . .
I am not sure I would invest too much either on a car with that much mileage.
a good ( trusted ) muffler shop should be able to weld in those flexes for less than that . I dropped my pipes ( disconnected at the head ) gave me about the extra inches I need but the trick is lineing up the parts correctly so the cat is square when you weld her up ( I had a buddy do it ) .
generic O2 sensors ( bosch ) can be has aftermarket and spliced in . I found that cheap and easy . You could look at a wreckers for the exhaust pieces you need and clamp them in , that might get you by ...
BUT ... it is all too common to shoot the messenger .. by that I mean your o2 sensors are telling you you have a cat issue , .. I would fix the flex issue first as you are upsetting the chemistry upstream of the S2 sensor.
I think vag com can actually report the efficiency of the o2 sensor and tell you if its getting old, I seem to remember doing that .. At 200K tho ... maybe time to look at a less "exhaustive" car . .
#4
AudiWorld Super User
I think I got mine at ecs tuning but its been a while.
try looking at this .. you will have to measure your od.
http://www.jcwhitney.com/pacesetter-...=c12774d75u0j1
try looking at this .. you will have to measure your od.
http://www.jcwhitney.com/pacesetter-...=c12774d75u0j1
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#7
Is your car a CA car? (Might be if sold originally in NY)
I would bet it would work fine as long as the inspection station does not look to close.
https://www.am-autoparts.com/product...l?m=971&y=2000
Shipping might be an issue. (Get it shipped to a friend in another state)
I would bet it would work fine as long as the inspection station does not look to close.
https://www.am-autoparts.com/product...l?m=971&y=2000
Shipping might be an issue. (Get it shipped to a friend in another state)
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Is your car a CA car? (Might be if sold originally in NY)
I would bet it would work fine as long as the inspection station does not look to close.
https://www.am-autoparts.com/product...l?m=971&y=2000
Shipping might be an issue. (Get it shipped to a friend in another state)
I would bet it would work fine as long as the inspection station does not look to close.
https://www.am-autoparts.com/product...l?m=971&y=2000
Shipping might be an issue. (Get it shipped to a friend in another state)
if the computer is ok with these pipes, and I can't see why not, I got shipping covered.
#9
My guess is any little difference in cat efficiency is well within the normal tolerance that occurs over the life of the system.
Double check in case there is something stupid, different threads on eth O2 sensors.
Double check in case there is something stupid, different threads on eth O2 sensors.
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