So I have this 2000 Civic SIR, factory with B16A... All stock except for a Cold air intake.
...anyways, in higher RPM I'm hearing a loud sputtering sound and there is quite the power loss, also in 3rd gear It wont rev past 6500, it feels like it's being restricted.. also as soon as you let off the throttle a bit the sound goes away.
Here's a Video http://youtu.be/BZyn7DXfGJo

The check engine light is on and it's giving a P-0420 which is a cat system efficiency code, but a clogged cat wouldn't cause that sputter would it?

Any help would be very appreciated.

Thanks

 

Has a tiny sound, might be a clogged cat, there was one user a few weeks back had a clogged cat and could not start the car.

 

Almost a sneezing kind of sound. Hopefully not a head gasket.

 

Check out your distributor cap and rotor, a loss of good contact with your ignition could cause this sputtering and hesitation at high rpms.

 

sounds like it could be an ignition problem so replace the car and rotor( u can test it by scrapping the connections clean with a Flathead screwdriver and if it gets better then replace.) but that car is as slow as a D series.BTW quit running the shyt out of it until you figure it out. i see the CEL light is on why not pull the codes and see what codes your throwing it way help because it could be another problem.

 

He did pull a code for the cat, it was stated under the video.

 

well then no the cat would not cause this problem but if its clogged it will affect performance and make it slow like it is.

 

looks like the car is picking up ok. But Its a weird sound I hear it on a lot of cars especially going from first to second when trying to catch traction. but most the cars I hear it on are all motor street cars.

Take the cat off and reset the ECU see if that does anything.

 

Ya man I only rev it like that for the video, its the only way I can get it to make the sound.

Tomorrow I'm going to pull cat off and test drive it to see if the power loss is still there.

 

The speed of the sound doesn't ever change, the only thing that changes is how loud it gets.

 

Check the condition of the plugs, it almost sounds like a dead cylinder.

 

Checked plugs and they look good. The car idles really nice and drives really nice up until its in about 5500+rpm, and it makes the noise only when at wide open throttle....

Also I tried checking for the sound under the hood and I could hear the sound but I couldn't pinpoint it because the intake was so loud.

 

Thanks, a few people have suggested this, I'll be sure to check it out

 

clogged cat wont do that...and u can eliminate the cat as the culprit by taking off the exhaust and driving it again open header to be sure...if u can swap out the distributor with a known working unit.....also, take a picture of your distributor to show the way it sits....u didnt advance/retard the timing did you?

 

Nope I didn't change the timing, however I think I found the problem today...

The cat is so clogged that in High RPM the pressure is releasing right at the cat flange, the exhaust gas is escaping past the gasket, which is making the sputter, and it's where I'm getting that funky smell...

 

good job make a video of it when you take the exhaust off and do some pulls i wanna see how fast it is lol