unusually quiet

[malice10985]

My flowmaster is like half as loud as it usually is. It is unusually quiet in my car. I cannot hear the car running if I stand more than 15 feet away from it.

Now on to the more routine stuff. I have a blinking SES light and multiple p0300 codes. The car feels like it has about 10 horsepower. It will not go above 70mph. Atap says under full throttle it is pulling about 5 degrees of timing for KR. The knock active counter stayed at zero.

We have a new large pothole in the threshold of our driveway and the last few times I have driven over it I have banged the bottom of the car on the jagged edges of the concrete. The exhaust rattles a lot now and I can hear a prominent leak in the header collectors.

I think I might have ruined/clogged the catalyst by crunching it in that huge pothole. I did a search and some people say that multiple misfires can be caused by a clogged cat.

I assume that a cat normally gets clogged slowly over time, not in the period of 2 days.

Originally I thought it was something to do with my cam, but it ran fine for 1500 miles. Why would it suddenly start acting up now?

Does a clogged cat make the exhaust quieter?

[speedy-v6-camaro]

Clogged cat will make the exhaust quiet and it will make your car feel like it has 10 hp too.

[MustangEater8251]

get under your car and check all your exhaust... see if there is a crimp in it...

as for hte CAT... it will do it but 90% of clogged cats are do to them being old, not damage... they get old, and desintigrate on themselves blocking up the exhaust.

[Seth]

I had to replace my cat because it was clogged at about 50000 miles. They did it for free though, said that the cat has a 75000 mile warranty.

[97rs4life]

If the cat went bad, wouldn't there be a nasty egg smell from the car? I am not sure, just heard that from searching around the forums.

[malice10985]

It is really really clogged now. It stalls at every stoplight and it won't rev over 2500rpm.

Before I leave work tonite, I am gonna loosen up the header flanges and collectors. I will also take out the o2 sensors. the engine will run like crap, but at least it won't kill itself.

A buddy of mine said that clogged exhast can quickly destroy an engine. I am not ging to wait and find out.

[ReodDai]

I hit my cat on some rocks in the road... crushed in internals. Wouldn't rev over about 2-3k and then it felt like it hit a wall. Exhaust was VERY quiet.

[malice10985]

<blockquote>quote:</font><hr>Originally posted by ReodDai:
I hit my cat on some rocks in the road... crushed in internals. Wouldn't rev over about 2-3k and then it felt like it hit a wall. Exhaust was VERY quiet.<hr></blockquote>

I bet that is exactly what happened to mine. I crushed its internals on that giant pothole.

How long did you drive around with it that way? Did it completely ruin your engine?

[malice10985]

took out the plug right in front of the cat. On 95-97 cars there is an o2 sensor there, but not on 98+ cars. I just had an old 13/16 sprark plug in the whole, so I took it out and it made a huge difference. THe car runs way better than it did, but not good enough yet. IT sounds like a lawnmower.

It was -13 degrees F outside when I did that, so my hands still hurt from working on cold metal in cold air.

When I got home I unbolted the header collectors. The car will sound terrible when I start it again, but That is better than ruining the whole engine from exessive backpressure.

[F1GT]

You can put ur hands on the tips to see how much flow is coming out and also go under and it the cat with ur fist to see if anything rattles. A clogged cat can cause a fire too.

[malice10985]

I drove around today with open headers. HAHA!! It was obnoxiously loud.

My catco cat and SLP loud mouth arrived today too. They will be installed first thing tomorrow morning.

THat SLP resonator is a joke. I shined a flashlight in it. It is nothing but a straight pipe. THat system is gonna be cool.