hope it works for you, too. i usually got the CEL after 20 minutes of driving also.

 

Lets hope... I've gotten where I dont fill up at Speedway, Marathon, or Independent 'Mom & Pops' who usually get their gas from the cheapest distributor and usually have crappy tanks..

 

Drove to Boston this morning to pick up my niece from the train station, about 30 minutes away and guess what!!!

The DAMN light came back on, WTF!!!!!

Im going with plan B. Replace 02 sensor. Ill order it and see what happens after that. If it does come back after that i guess im gonna have to do the cat. If it does come back after the cat, then i guess im gonna have to learn how to live live with the f*cking cel...

 

Well, was worth a shot... I say give it another tank or two before doing the O2.. let it get clean.

Ya know, they have 'catalytic convertor cleaner'.. dont know if its worth a damn, but if the cats are going anyway, it cant hurt.

 

i have to wait for the 02 sensor to get here anyway, so im gonna keep putting shell v power in the meantime to see what happens.

as for the cat cleaner, what is the exactly?

 

Dont know for sure, I've only seen it. Works kinda like SeaFoam as far as I can tell. Auto parts store should have it, or here:

http://www.amazon.com/Catalytic-Conv.../dp/B000AMBO9O

http://www.carparts.com/CATALYTIC-CO...2190_10618.car


Could be a dirty O2 too...


Hope something works other than replacing the cat...

 

After diagnosing the car at school (UTI) with the snap-on modus tool, i learned that my
o2 sensors are working propertly. I dont think my cat is bad, so with a little more research i learn that the p0421 can be sent do to a bad combination (combi) valve or a bad vacuum line to the combi valve. Im gonna check it after the snow stops. I will figure this out eventually, or atleast before my next state inspection is due

So far: Plugs are good, O2 senvors are good, cat seems good,

Suspects: combination valves, wastegate itself, or wastegate actuator.

after i get through with these ill look at whatever else i or the next guy can think of.

 

Now that you mention it, I do remeber seeing that on a forum before... audiworld? Forget..

 

i read it here, and being that ive heard of people changing cats and sensors with no luck, i figured this would be worth a shot since it pretty much is free to do. Nothing to lose.

http://answers.yahoo.com/question/in...0104900AA09JlR


and this helped too:

The Kombi valve is the valve that lets the secondary air pump admit air into the exhaust stream at startup and sometimes idle to heat up the catalytic converter. This is so the cat will work at its maximum efficiency. The EGR (exhaust gas recirculation) valve recirculates unburnt exhaust fumes back into the combustion chambers (cylinders) to increase the quality of emissions. As far as the diverter valve is concerned, in ETKA, it is refered to as a "change over valve"; so all of these are different valves.

http://forums.vwvortex.com/zerothread?id=876611