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Need help with Cat repair and locaton

2810 Views 8 Replies 3 Participants Last post by  Steve in Chicago
Hi everybody.

I am in desperate need of some help.
My 03 GLS (that has 117k miles on it) is in the repair shop right now and i think the mechanic is giving me the run around.:banghead:
I know that my cat needs replacing and i am attempting to get him to do this but he says there is a problem and he can't. I first off just wanted to get the car straight piped so i can get it back on the road and complete some other mods to it but he says that the problem cat is in the exhaust manifold:confused: is this for real? ? What should i do?:confused:
he says that he can get the needed part for $300 and labor for $160. c'mon son!

Y'all help me out now and give me some suggestions. I am so ready to send this car to the junkyard.
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If you have the 1.8t engine, the CAT is bolted directly to the output side of the turbocharger with a three bolt flange. It's not like some cars where the CAT is under the car and you can simply cut it out and clamp in a straight pipe. One way to replace the CAT with a pipe would be to get a "cat-delete" or "test" pipe designed to fit that specific car. Those run about $100~$175 and require some additional trickery to keep the engine computer from seeing what you've done and lighting up the CEL. If the car is to be owned in a place that does a visual inspection as part of emissions testing, the "test" pipe may keep you from passing.

Volkswagen Passat B5 FWD 1.8T > Exhaust > Test Pipe > ES#1844140 B5 1.8T Race/Cat Delete Pipe Kit - ATP-VVW-138

Is the $300 part he quoted a new replacement CAT?

OEM / Performance Parts for Audi, BMW, Mercedes Benz, Mini, Porsche & Volkswagen - ECS Tuning
Hi Steve.

Yes I have the 1.8T engine. What additional trickery are you speaking of?

My car is registered in Florida even though I live in Maryland (military). Last checked, we don't do emissions in Florida and I am exempt from any of those tests while here in the DMV.

I am under the impression that the $300 part is a OEM replacement part but not totally sure if it is a CAT. So are you telling me that there is a CAT in the exhaust manifold?
If you have the 1.8t engine, the CAT is bolted directly to the output side of the turbocharger with a three bolt flange.

The exhaust manifold is the horizontal part on top. Three bolts attach the turbo which hangs off the bottom of the manifold. Bolted to the output of the turbo is the CAT (on the left side with the O2 sensor sticking up and out of it).

Ask the mechanic what the $300 part is.

To fool the engine computer into thinking there is a functioning CAT there when there is not, you need to do some modifications to the second O2 sensor.
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ok, i will be asking him that tomorrow. thanks for the visual:thumbup:
I see that Steve is quicker than me:hatoff:, but here's another picture...

You can see the catalytic converter in this picture of my 2001.5 AWM, taken standing in front of the right (US passenger) headlight:

The rusty colored objects, beginning at the front, are:
  • the turbo
  • the pre-cat oxygen (O2) sensor
  • the catalytic converter itself

The post-cat oxygen sensor is further toward the rear of the car and below, out of view. The pre-cat O2 sensor is actually screwed in to the cat housing--the flange that bolts the cat to the turbo is in front of it.

The "trickery" is this: the ECM monitors the pre-cat and post-cat O2 sensors and expects to see a change as the exhaust passes through the cat. If the two sensors read essentially the same, the cat isn't working, so you get a CEL.
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ok Fresco, i think i got what you're saying about the "trickery" but then in that case i would have to get the CELs cleared every time they appear right?

this doesn't look hard to install, i wonder if i could do it myself?
just as an update- the mechanic wouldn't tell me what part he had for my car at $300, so i decided to take my car home. i really felt like he was trying to get over on me. i will be bringing my car home tonight and getting help from a friend to attempt to repair it soon.
thanks for the pictures and the links folks.
the mechanic wouldn't tell me what part he had for my car at $300
That doesn't sound good. I'd go elsewhere.
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