hey guys
I went out to a dealership today and test drove a 97 DC2. It ran great and only had approx 84k miles. Carfax looked clean and with only one previous owner. Price wasnt bad either. Anyways, during the test drive, the car made an odd but slight buzz noise while pulling off and stopping. It didnt actually sound like a loud rattle such as the noise i heard on my friend's 95 DC2 when the heat shield on his header was loose. I couldnt quite pinpoint the where the sound was coming from, but I assume it might be the heat shield on the cat converter.

Cliff notes:
Slight but noticable ::Buzz:: when peeling off and coming to an almost complete stop. Also makes the noise when reved slightly. Doesnt sound quite like a rattle.

Thanks for any input!

 

ttt

 

It could also be the catalytic converter brick that has come loose, and is shaking around in the cat. You will know this is the case after you have spent hours under the car poking at things while someone is revving the engine.

 

cat converter brick? hmm never heard of that before. would this require me to get a new cat converter?? also, another thing mentioned on the TI forums is it could be bad welds inside the A-pipe? but they also mentioned that the buzz is more prevalent in the 3-4k rpm range but mine seems to occur before that.

 

I can hear mine all the time it's just that it is much more noticeable from 3-4 k thats what they are trying to say

 

yea but I cant hear mine anymore after peeling off. its kinda like during the 2k range, then its silent.

 

It could be the cat, and it could also be the part of the header befor the cat. If it is stock, it is a pipe-in-pipe design and can start to rattle. Many people use it as an excuse to get a new header, present company included.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rev_DC2 &raquo;</TD></TR><TR><TD CLASS="quote">cat converter brick? hmm never heard of that before. would this require me to get a new cat converter?? also, another thing mentioned on the TI forums is it could be bad welds inside the A-pipe? but they also mentioned that the buzz is more prevalent in the 3-4k rpm range but mine seems to occur before that. </TD></TR></TABLE>

i think hes refering to the honeycomb in the cat...which has deteriorated. If you think its your cat, try pulling it off the car, and see if theirs chunks of honeycomb

 

I had to remove my cat converter heatsheild recently, got new headers and they fit differently and pushed the cat up, causing it to rattle at low rpms (starting off), tore it off and rattle went away, id try a few things before just buying a new cat or headers or whatever.

 

what can cause a cat converter to go bad? unburnt fuel? According to carfax this cars never failed emissions or anything so its probably just something loose. Is it just me or does it seem like a lot DCs have rattling or buzzing issues at some point. And yes this car is completely stock minus the aftermarket headunit(radio).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rev_DC2 &raquo;</TD></TR><TR><TD CLASS="quote">what can cause a cat converter to go bad? unburnt fuel? .</TD></TR></TABLE>
most cases i hear are of cars running extremely rich