help needed please

[mr. greatwrench]

had the cat. replaced on my 02 sierra last year 5-7-08 after several stalls
paid out the *** to get it done. Now just over one year later truck
started losing power, running ******. Took it to autozone had them scan it
random misfire cylinder came up. Drove to the shop that fixed it last year
had them look at it . The owner calls me back and says my cat is clogged. just over a year ago he replaced it. He proceeds to imply that i did something wrong when replacing plugs and 02 sensor. I did all this after he replaced the converter. Needless to say his warranty had expired just over a month ago , and by 3000 miles. How is it that the original cat lasted for 112,000 miles and the new one didn't make 15,000? I got into it with him . Took my truck out of there. Now I'm in my driveway I have the cat loose but can't manuever it out . Any Advice would be appreciated. Thanks All.

[leolkfrm]

Did he give a reason why the original cat was plugged?
you will nee to loosen the exhaust from the cat back to get room to slide it off the pipes

[mr. greatwrench]

No reason given . I suspect that he mis diagnosed the original problem and took me for a new cat . I am having trouble getting clearance from the ground . I put the cat back on for now. Need to sip a tall cool one and contemplate my next move. Thanks for the input.

[merlin5577]

I believe it is federal law that all replacement emissions equipment is covered by a 24 month 24K mile warranty; http://www.epa.gov/oms/consumer/warr95fs.txt

Get an attorney.

[badtothebowtie]

good find merlin

[hotrodpc]

Yep, glad you found that merlin. Also unless it has changed, many people are not aware on a brand new vehicle, law states any emmisions parts that fail inside of 50,000 miles, the manufactuer must replace. So even if you have a 3yr/36,000 bumper to bumper warranty and your CAT, or EGR, or ECM goes out at say 48,000 the manufactuer must replace it.
I have a feeling your CAT was clogged when he sold you the new one a year ago, but he did not correct the issue that caused your CAT to clog. So this one prematurely got clogged too. I would imagine your random misfires are lean conditions that create alot of, and excessive cylinder head heat. Need to find out why that is happening.

[gmctrucks]

Sorry to hear about your troubles you might check to see if the right O2 sensor was put on.
Good luck! GMC

[bradrhale]

why are we still lookin at the cats as a possible problem. a random misfire can come from other problems as well. i believe i would get a second opinion before jumping to conclusions.

[hotrodpc]

Yep, thats my point brad. Find the random misfire condition, which I will guess it to be a lean misfire condition, and its running the cylinder temp up and overheating and melting down the catalyst in the converter. I think this may being looked at backwards, the misfire is causing the converter to go bad, not the converter causing the misfire. And now the converter is jacked the misfire is more prominate and noticeable. Just a guess and suggestion.

[mr. greatwrench]

I want to Thank everyone for their responses. I'm in the process of getting a second opinion . I agree with Hotrodpc, I think it is being looked at backwards . Keep you all posted thanks again!