I was wondering what the symptoms were of a clogged and possibly really fooked up pre-cat was. I'll tell you what the problem is. When I am driving, it's ok if I barely press the pedal, when I floor it nothing really changes and it almost feels as if it's losing boost. I also get a wierd type of growl under the car, and it sounds like a hole in the exhaust.....my theiry(spl??) is the pre-cat or maybe I blew a gasket for the exhaust, would this all contribute to low power? The turbos ARE working properly, and I'm gonna go buy a boost gauge ASAP, probably even tomorrow. I appreciate any help, and it's not the engine, the shop it was just at said the engine is fine....compression checked out ok. So anything guys? Thanks again.

 

You bring in a car with boost problems and they don't see anything wrong with the car?? Looks like there is some more investigation needed. A plugged cat can eventually cause issues with the boost levels but you would also notice lots of other issues.

Not saying that it isn't the pre-cat but get your boost numbers and that will at least give you a direction. Did they check your boost numbers vs rpm at the place that checked the motor??

 

no, no. I didn't take it there for boost problems. I took it there to have them fix my starter. They just checked that, they didn't drive the car hence why they didn't fix this problem, although it does concern me that they didn't hear this noise or just didn't pay attention to it. Anyways, I'll get the gauge and let you know what the numbers are ASAP ok? And no they didn't check the boost numbers vs RPM.

 

I'm not sure a clogged precat would cause your exhaust sound to get luder or "growl," but as far as it can definately cause the poor performance issues. I had a clogged precat and couldn't get anything above 0psi on primary or secondary boost.

 

No, I believe that I have a clogged pre-cat, yes, but I also think that there is a hole in it somewhere also or maybe I blew a gasket etc. Also, I was out today and decided to **** around a bit with my buddies so I did some donuts.....about 4 or 5. I did about 100 MPH on the freeway home after this, not right after I did that though, and it was only for about a 4-5 min. drive home. Anyways, once I got home my turbos were glowing RED along with my pre-cat now I know for sure that my pre-cat is clogged. Well, since I got the 3" M2 dp for X-mas I have to put it on now. My buddies are gonna do it for me for $50! I'm just lazy right now and I have money, so why not give them a chance to get some right?

 

yay, downpipe

 

exactly!