spuntuckywoowoo

Hi im new here and also a first time audi owner. I have a 98 a6 quattro that i bought from my sister to help her out and it runs good but not for very long so i took it to a shop and they said i needed to have the maf and throttle body replaced so i did that and it still ran the same. So after that we figured out the cats were plugged, any advice on just getting it straight piped? will it run right?

uberwgn

Spun, welcome aboard. Does Oregon have state inspection?

blink

I took off my cats when I rebuilt my exhaust. Runs the same. I was hoping for a bit more power, but it's the same. Check your local emission regulations, if you need to pass a smog, you may need them.

spuntuckywoowoo

Thanks for the replys. The county i live in doesnt have any emissions or anything like that so im good on that one.

Highmile

You should be asking yourself why the cats failed. Are you burning something other than quality gasoline? oil or coolant? Burning coolant will cause your catalyst to melt down and plug. Recently I worked on a 1.8t which idled fine but had no power under load. Car was burning coolant, converter was toast. I got a good used cat for $80 and three hour round trip.

If you chose to go catless: Without cats, you will get a check engine light. There are workarounds. Code out the O2 sensors so the ECU won't display CEL for cat inefficiency. Using spacers or spark plug antifoulers to get the O2 sensors out of the exhaust stream, thus tricking the sensors into seeing lower emissions. Without cats your exhaust will smell, no workarounds.

I would encourage you to replace the cats. Gutting cats and straight pipe is hack/ghetto fix. There must be someone parting out a similar Audi. If not, try aftermarket cats.

Prospeeder

Passats have the same exhaust and cats, as well as A4's. So finding a 2.8 with good cats shouldnt be hard. But if you really want to remove them just use a cut off wheel and make a partial cut and peel it open and scoop the guts out, and then weld it back up.

spuntuckywoowoo

Thanks for all the advice! So i got it straight piped (for now) and i is still running like crap. The only way i can really explain it is just a serious loss of power. Does anybody have any ideas at all? It runs but when you are driving it, it is really sluggish and will eventually stall. Hope that helps

SloopJohnB@mac.com

Other than that, it sounds more like a vacuum leak somewhere. VCDS is good to chase down any codes. You could also go old school and check compression, etc. When were spark plugs last replaced, are they in tight, is there oil on the outside of the plugs indicating a cam cover gasket leak, are the plugs burning clean or black, etc. etc.?

blink

This is out of left field, but sometimes can be the problem. When your losing power, and the car is running rough, what is the speedo doing? Theres a speed sensor that goes bad, and sends the wrong message to the ecu, making the car run like crap, and eventually stall. Watch your speedo, if it goes crazy, thats the issue.

Prospeeder

Have you checked fault codes?