996 C4S in trouble (bad cat CEL and scary sound)
12-07-2012, 09:09 PM
#19
Pro
Thread Starter
Looks like you guys were right, thank god!
I changed the oil and cut open the old filter. Not a trace of any metal, plastic, or anything!
Started up the car and no rattle. As soon as it warmed up a bit the rattle returned. I can sort of agitate it with a rubber mallet.
Looks like I'll be ordering some cats this weekend.
I changed the oil and cut open the old filter. Not a trace of any metal, plastic, or anything!
Started up the car and no rattle. As soon as it warmed up a bit the rattle returned. I can sort of agitate it with a rubber mallet.
Looks like I'll be ordering some cats this weekend.
12-07-2012, 09:35 PM
#20
Rennlist Member
12-08-2012, 01:47 AM
#21
Nordschleife Master
Looks like you guys were right, thank god!
I changed the oil and cut open the old filter. Not a trace of any metal, plastic, or anything!
Started up the car and no rattle. As soon as it warmed up a bit the rattle returned. I can sort of agitate it with a rubber mallet.
Looks like I'll be ordering some cats this weekend.
I changed the oil and cut open the old filter. Not a trace of any metal, plastic, or anything!
Started up the car and no rattle. As soon as it warmed up a bit the rattle returned. I can sort of agitate it with a rubber mallet.
Looks like I'll be ordering some cats this weekend.
EDIT: Never mind. I just saw your other post. While you're at it, look for sport mufflers. A little more pricey, but you can get the OEM Porsche sport exhaust. The combination of the Fabseed cats and the Porsche sport exhaust is just exhilarating on the track!
12-08-2012, 02:02 AM
#22
Pro
Thread Starter
So I took the bumper cover and heat shield off and with the car cold (obviously) I started it up and stuck my ear right on the cats. It is definitely the source of the death rattle. Already shopping for a set of sport cats. It looks like Cargraphic has the best price for 200 cell. That is except for some company called NHP which I can't find much detail on.
The Cargraphic aren't x-pipe though. Next in line is FVD x-pipe but I don't think they have any in stock here in the US right now (says 6 days before they ship). Finally Fabspeed is still an option but their website doesn't mention available stock or lead time.
Oh and I already have PSE and am looking forward to the sound of these high flow cats!!
The Cargraphic aren't x-pipe though. Next in line is FVD x-pipe but I don't think they have any in stock here in the US right now (says 6 days before they ship). Finally Fabspeed is still an option but their website doesn't mention available stock or lead time.
Oh and I already have PSE and am looking forward to the sound of these high flow cats!!
12-08-2012, 03:04 PM
#23
Rennlist Member
Fabspeed builds them to order. If I could do it over I'd go with the FVD xpipe unless I was going to match the cargraphics with their mufflers. Can't go wrong with either in my opinion.
12-09-2012, 12:50 PM
#24
FWIW I am running the 200 cell X-pipe cats from Maxspeed Motorsports (NHP). I selected them after researching used cats, FWD, and Fabspeed.
I am very happy with the results. The car sounds slightly meaner and seems to rev a little easier. Quality of the parts is excellent and the installation was straightforward. It took a full morning but I took my time and also polished my existing mounting brackets just because the new exhaust looked so shiny :-)
The cats include tapped holes for both oxygen sensor locations so they work without modification for both 2002+ and 99-01 cars.
I have noticed that the engine hesitates a little when cold for the first 30-60 seconds of driving and I think it is related to the reduced backpressure when the fuel management system is still in open-loop mode (but that is just my guess). I assume this would have also occurred with any other 200 cell cat.
I was very impressed with Fabspeed as well but the price (and shipping for me) was a little higher. My guess is they both probably use the same or similar underlying cat.
I am very happy with the results. The car sounds slightly meaner and seems to rev a little easier. Quality of the parts is excellent and the installation was straightforward. It took a full morning but I took my time and also polished my existing mounting brackets just because the new exhaust looked so shiny :-)
The cats include tapped holes for both oxygen sensor locations so they work without modification for both 2002+ and 99-01 cars.
I have noticed that the engine hesitates a little when cold for the first 30-60 seconds of driving and I think it is related to the reduced backpressure when the fuel management system is still in open-loop mode (but that is just my guess). I assume this would have also occurred with any other 200 cell cat.
I was very impressed with Fabspeed as well but the price (and shipping for me) was a little higher. My guess is they both probably use the same or similar underlying cat.
12-10-2012, 02:17 AM
#25
Three Wheelin'
dotframe, that is definitely just the cats. CEL goes on, and there is a death rattle at idle. Thats' the stock cats 
. The inner chamber has become dislodged and is now rattling around with the engine exhaust pulses. I used to replace mine almost annually, until I replaced them with sport cats. Not only do the sport cats stand up to track use better than the stock cats, you can also pair them with Porsche sport exhaust and you will get a deliciously sounding rumble at idle and a beautifull roar at full throttle when you exit the apex turn heading down the main straight 
.
KrazyK, here's a few videos for you. If you like them, maybe you and I can head out for a weekend at the Circuit of the Americas in Austin and have fun at the newest F1 track!!
Watkins Glen, NY
http://youtu.be/PNM2NZe12kc
BeaveRun, PA
http://youtu.be/sM7GytnWKMc
<iframe width="480" height="360" src="http://www.youtube.com/embed/sM7GytnWKMc" frameborder="0" allowfullscreen></iframe>
. The inner chamber has become dislodged and is now rattling around with the engine exhaust pulses. I used to replace mine almost annually, until I replaced them with sport cats. Not only do the sport cats stand up to track use better than the stock cats, you can also pair them with Porsche sport exhaust and you will get a deliciously sounding rumble at idle and a beautifull roar at full throttle when you exit the apex turn heading down the main straight .KrazyK, here's a few videos for you. If you like them, maybe you and I can head out for a weekend at the Circuit of the Americas in Austin and have fun at the newest F1 track!!
Watkins Glen, NY
http://youtu.be/PNM2NZe12kc
BeaveRun, PA
http://youtu.be/sM7GytnWKMc
<iframe width="480" height="360" src="http://www.youtube.com/embed/sM7GytnWKMc" frameborder="0" allowfullscreen></iframe>
Some great laps! Btw what's with lotus drivers - had the same thing happen to me this summer - 3 opptys to let me by and no hand signal - marshals eventually had him pit
12-29-2012, 12:19 AM
#26
Pro
Thread Starter
Just a quick update for anyone searching on the same symptoms.
I got new 200 cell cats from Cargraphic.
The old ones came off really easy and the new ones bolted right up. Only 2 small issues came up. Since the O2 sensor placement is slightly different, I had to re-route one of the cables a bit. Also, on the two pre-cat sensors there is a small bolt that goes in on the bottom side. I forgot to put it in at first and the car was throwing all sorts of new codes (as well as sounding like a pressure cooker) and I just about crapped my pants. Anyway, one of those holes had some bad threads but I got that worked out.
Aside from the threads noted above these cats are extremely well done. The stamp on the cats themselves notes they are actually HJS built specifically for Cargraphic. These sound amazing along with PSE!! Also the car feels like it gained a bit of grunt across the whole RPM band. I think this was probably due to the old cats being a bit clogged more than anything else.
Car is running great with no scary sounds or current or pending codes. Woohoo!
I ordered the cats direct from Cargraphic in Germany and after a slight delay in shipping they got here in 2 days! I know this may sound stupid but one of the main reasons I chose Cargraphic was due to their responsiveness to email. Thomas Schnarr replied to an email within like 30 minutes of sending it. And when the package got hung up in US customs, Cargraphic sent me an email alerting me and I was able to call fedex and get it moving the same day.
I got new 200 cell cats from Cargraphic.
The old ones came off really easy and the new ones bolted right up. Only 2 small issues came up. Since the O2 sensor placement is slightly different, I had to re-route one of the cables a bit. Also, on the two pre-cat sensors there is a small bolt that goes in on the bottom side. I forgot to put it in at first and the car was throwing all sorts of new codes (as well as sounding like a pressure cooker) and I just about crapped my pants. Anyway, one of those holes had some bad threads but I got that worked out.
Aside from the threads noted above these cats are extremely well done. The stamp on the cats themselves notes they are actually HJS built specifically for Cargraphic. These sound amazing along with PSE!! Also the car feels like it gained a bit of grunt across the whole RPM band. I think this was probably due to the old cats being a bit clogged more than anything else.
Car is running great with no scary sounds or current or pending codes. Woohoo!
I ordered the cats direct from Cargraphic in Germany and after a slight delay in shipping they got here in 2 days! I know this may sound stupid but one of the main reasons I chose Cargraphic was due to their responsiveness to email. Thomas Schnarr replied to an email within like 30 minutes of sending it. And when the package got hung up in US customs, Cargraphic sent me an email alerting me and I was able to call fedex and get it moving the same day.
