Choking at High Rpms

Cbussilver01es · Post by **Cbussilver01es** » Thu Mar 29, 2007 8:19 pm

Hey all, I gotta question for ya real quick. After doing a few searches on here I still havent completely got a good answer to this question. My car seems to have no acceleration at all anymore and my intake seems louder and you can feel the engine basically choking. Not to mention that Ive had that infamous P0420 catalyst code for months. Now I know what ppl will say so I'll go ahead and say it. The Plugs, Coil and wires are all new. Is my cat clogged real bad and causing the drop in performance? Ive noticed my exhaust smells like straight gas so is it my cat?

hansken_yo · Post by **hansken_yo** » Thu Mar 29, 2007 9:32 pm

I'm under the impression that if the cat is bad you'll have a nasty sulfer smell. (rotten egg).

If I'm reading this right your throwing a CEL? Have you had your sensors checked? O2 and exhaust?

Cbussilver01es · Post by **Cbussilver01es** » Thu Mar 29, 2007 10:00 pm

yea downstream is basically brand new, upstream is fine. And the smell kinda smells like rotten eggs along with straight gasoline

kc2005ptgt · Post by **kc2005ptgt** » Fri Mar 30, 2007 12:27 am

(cat)

Yes, probably your cat. Take it off, stick a crowbar in it, and bang it around until all that crap falls out. Then put it back on, or shove in a straight pipe and just bypass it all together.

You might have a clogged cat, so you have to replace it --- best bet, take it to a reputable muffler shop and have them check out your auto.

BlackRoseRacing · Post by **BlackRoseRacing** » Fri Mar 30, 2007 5:21 am

Also just an FYI:

EXTENDED FEDERAL EMISSIONS: 96 Month or 80,000 Miles

If your still covered under the FED emisions, get a new converter for free and be done with it...

Cbussilver01es · Post by **Cbussilver01es** » Fri Mar 30, 2007 11:42 am

BlackRoseRacing wrote:Also just an FYI:
EXTENDED FEDERAL EMISSIONS: 96 Month or 80,000 Miles
If your still covered under the FED emisions, get a new converter for free and be done with it...

Yea thats what a few ppl told me, sad thing is the odom has 97,000 on it, but the actually mileage is less bc of the new motor in it.

Kc2002acr wrote:Yes, probably your cat. Take it off, stick a crowbar in it, and bang it around until all that crap falls out. Then put it back on, or shove in a straight pipe and just bypass it all together.

I planned on guttin it, but the damn nut and threads underneath the car is so rusted its not funny.

dgodard · Post by **dgodard** » Fri Mar 30, 2007 3:25 pm

To take off cat do you need to cut pipe? Or only bolts ?

kc2005ptgt · Post by **kc2005ptgt** » Fri Mar 30, 2007 3:35 pm

bolts... cat bolts directly to the header

dgodard · Post by **dgodard** » Fri Mar 30, 2007 3:44 pm

But other side of cat is welded to pipe right? I'm asking because maybe i'll gut it...

kc2005ptgt · Post by **kc2005ptgt** » Fri Mar 30, 2007 3:44 pm

there is another clamp/bolt to loosen up also, and the piece pops out of the pipe.

Cbussilver01es · Post by **Cbussilver01es** » Fri Mar 30, 2007 10:50 pm

UPDATE!! I gutted the son of a bitch and it runs BEAUTIFULLY! it seems louder than a mofo but it runs good! I tell you want tho that cat was hard to pull off from the rest of the exhaust.

kc2005ptgt · Post by **kc2005ptgt** » Sat Mar 31, 2007 12:35 am

did ya get any cat codes???

Cbussilver01es · Post by **Cbussilver01es** » Sat Mar 31, 2007 10:55 am

kc2002acr wrote:did ya get any cat codes???

Nope not yet.

dgodard · Post by **dgodard** » Mon Apr 09, 2007 2:59 pm

I'll gut it too then!

BlackRoseRacing · Post by **BlackRoseRacing** » Tue Apr 10, 2007 7:01 am

1 - If you plan on gutting it, make sure you run a pipe through the middle to help aid in the exhaust flow since the hollowed out converter will be an exhaust restriction

2 - If the core is still inside the converter in one piece, junkyards pay a good $ for cats now since scrap metal is ^^^ in price. Here in WNY the average going rate on a used cat with a solid core is around $40 and ^ depending on the converter size.

3 - Just install a high flow universal cat with EPA paperwork stating the converter is legal. My turbo daytona ran a dynomax high flow cat that would support a 400+CI bigblock and it cam with all the paperwork stating it was EPA legal and I did not have to worry about any inspection issues.

......just my 2 cents....

gilly02le · Post by **gilly02le** » Tue Apr 10, 2007 12:43 pm

plus a magnaflow high-flow cat is only about 70 dollars at most parts-stores... and you will not feel any loss by installing one instead of a hollowed cat.. i went from no cat, to a 2.5" high flow cat, and its feels every bit as fast.. and its a bit quieter, and hell of a lot less raspy..

dgodard · Post by **dgodard** » Tue Apr 10, 2007 2:29 pm

Thanks by advices BlackRoseRacing and gillyo2le, i guess i'll doing option # 2 and 3