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Showing results for tags 'exhaust/cats'.
2002 C2, 95k miles, original exhaust and O2 sensors. A few months back the CEL went on, Durametric says P0420: Porsche fault code 40 - Cat. conv. efficiency bank 1. CEL has stayed on so I investigated further. Pre- and post-cat O2 sensor voltages shown in attached charts, upper chart for Bank 1 and the lower for Bank 2. Warmed up the system at idle, then throttled up to 2.5 - 3k three times, two short, one long, during which time all sensors went near zero. It looks like Bank 1 (upper chart) post-cat sensor is showing a problem while Bank 2 (lower) looks fine. (I started capturing Bank 2 after Bank 1) Also for a few years there has been a little rattling on the driver's side exhaust which I've suspected is a failing cat, but the exhaust system has not been recording any faults until now. After having read a few related threads, it seems fairly certain that the Bank 1 cat is failing, perhaps with a loose element that reduced cat performance after the third throttle bump in the charts below. I'm leaning that way because it appears the sensors are all reporting data at about the same rate, oscillating when expected, except for post-cat Bank 1's sensor which begins the capture looking like it is largely reporting correctly but ends with oscillations that shouldn't be there. There has been no perceptible change in performance, and I have over a year until the next smog inspection, so there's time. Does this information indicate a pretty strong likelihood of a failing Bank 1 cat? Or are there additional diagnostic steps I should take to eliminate other causes?
Im new to the site, just purchased my first Porsche, 2004 996 C4S cab, 31k miles. I live in PA, flew to mississippi to buy it and drove it home. I purchased the car from the original owner, a 65 year old orthopod (I say this because it means to me that the car was never abused). I purchased the car from the doctor but picked it up at Porsche of jackson following the dealer doing a 30k service, they told me all was well and i need not expect any major cash outflows soon after my purchase. So I drove 1200 miles without a problem, now I'm home in pa and becoming skeptical of my purchase. Here's why, 1. I now hear a light rattle from the passenger exhaust for the first few miles after startup each time I drive regardless of whether I just drove it 10 minutes prior...sound generally goes away after 5 minutes. Checked the cats with mallets, checked the exhaust clamps..can't see a problem..am I over thinking a war up sound, is this normal, or do I have a prob that needs to be checked by a tech? 2. Possibly, and if so, largely my fault...every car I have had as automatic lights, meaning they go off when I turn off the car. Two nights ago I left the headlights on all night, went to drive her in the morning and she was fully dead, had to jump the fuse box etc.. Just to get to the battery, when I did that, the jump wasn't enough to get the engine turned, aaa came and got it going with a power pack. They told me I was at 14 volts, but my cold crank amps were at 490/850, and " I could have a problem in a few days". After this car worked fine beside my #1 issue, and no problems starting or with electrical. Despite having made the car my daily driver since I purchased it last week, today I tried to leave my office and got no start. So I pulled the key out of the ignition, tried again, and it worked...same thing each of the three times I've tried driving it since...is this the battery needing replacement, the start, or something else? I figure the battery, but why the problems after two days of continuous driving? Some of my coworkers have Porsches and all of my family are life long owners too, they all think I am overthinking everything. My father is a VW, Mazda, and Volvo dealership owner, and other dealership owner in the past he thinks the exhaust noise is "normal". Comments and/or suggestions would be appreciated. Thanks, BW