went to the track tonight . On my last run I could only get 94mph and the car sounded bad . Went back to pit area and started looking for a problem .Couldnt find any hoses , vacuum line , off or loose .Didnt want to take any chances so I cut the cog belt off . And it still sounded the same .Like a 4 cylinder with a big muffler on it. A have heard some have failed....Any one out there that has had this happen that can tell me what symptoms they heard or felt after they went bad ?

 

Rev the motor and see if the sound is coming from the cat.

 

Jack it up and drop the driver side cat. For some reason, if the cats go, it's almost always the driver side.

How long have you had the RT's and how many miles have you put on them?

Oh, and the sound should be a muffled deep sound...and your car will DEFINATELY feel way slower...totally plugged up. If's its just a minor loss of power, maybe you have an exhuast leak, either at the head, or somewhere else in the exhaust system.

Do you have headers? What else?

 

Its a muffled sound and its a big drop in power . The cats have been on for about 8 months...about 4,000 mile .plenum, heasders ,cats, stillen cat back , vortech

 

sounds like a vacuum tube or hose loose, like i said check the cat for sound rattling

 

The exhaust sounds totally diff. I dont get that sound when you let off the gas [ totally free flow sound ] One thing I did notice is that the A/F gauge would drop down into the mid 13's under light throttle and 3,300 to 3,800 rpm's .

 

When my RT cats failed it was both of them that went bad. I had a 50% drop in power thoughout the power band, most noticable in the lower rpms. The sound is more muffled and it felt like the car bogged from the start.

I would raise the car and isolate the sound. IMO it sounds like it could be either of the 2 suggested issues. (RT cats or loose intake hose or something similar) My money is on the RT cats only because several others have had this problem including myself. You would be the 12th person within the last two months to have this issue. For the record I installed Crawford cats after my RT's went bad.

 

I just got done jacking the car up and checking every thing out. nothing loose no pinched hoses .Went through the whole intake , all the vacuum hoses . I took it out and got on it a little...it doesnt even rev as fast as it did before the SC install...the cog belt is cut off.... Thanks whosdady...that discribes it perfectly...I got to think thats the problem

 

Booger....drop the cats! That's the only way to find out. Start with the driver's side.... Based on your written description, it now sounds like it is most likely the cats.

Post a pic of the inside of the cat after you take it off.


Good Luck!

 

I tried to take off the cats today...I couldnt get to one bolt on the header collector .So I put it back together . I'll just let the shop do it .Taking it in tuesday

 

if it's the passenger side, You'll need like 4 long extensions and a universal joint...then you losen it from uptop...in the engine compartment. Driver's side is a *****...you need a shorty wratcheting wrench to make it easy.

It's a difficult job without a lots of exentions and small wrenches...small hands help too.

 

Keep us posted, I wish I had maybe chose different cats now after hearing all of this.

 

12SecZ....even with all the stories....it is still a small failure rate, so I wouldnt worry too much. Just think...once they fail, you just gut them into a nice shiny straight-pipe. And if anyone looks underneath, or jacks up your car...you appear to have fully functional cats.

That coupled with Skidazzles little O2 sensor feedback device, and you'll never have a CEL for 02..

 

That will work until he needs to have his car emmisions tested. In St. Louis you wouldn't pass with gutted H/F cats. Not to mention the fact that RT probably wouldn't take them back if they were gutted. $500 down the drain.

Other than that it is a great idea GQ I just read of a new S/C that had Xerd headers. Its just like having straight pipes and his dynos were pretty high for 7psi. It makes me consider going to a straight pipe.

My only concern is getting pulled over for excessive speed and having my car tested. The 10-15 rwhp gain isn't worth the price of my car... I drove my Supra for 8 years with a downpipe and luckily didn't have any problems. My Stealth on the other hand was nearly impounded.

 

Im going to get the tools I need to take them off Monday . And I'll know for sure then .From what Im hearing RT isnt very good with replacing them .Even if they do , and want the bad ones back ...my car would be down the whole time .Thats why I do think I will just hollow them out . I understand that there is going to be cats that fail..but they should be more helpful with the ones that do. You would think that they would think there reputation is more important than a the 500 bucks

 

the mystery will begin if the cats are compeletly fine....

 

Where did yo buy the RT cats? I would contact them and see if they will refund your money. Granted you may have to send them back to RT but at least you wont be out the $. RT does not refund a dime or pay for the return shipping of bad cats.

It looks like you have a crawford plenum. Contact Doug and see what he can do for you.

 

Got the cats thru Stillen .When I get them off and call Stillen and then RT I will make up my mind .If they replace them...I may over night some thing [test pipes , other cats ] to me and sell the RT's when I get them

 

I just got the passenger side cat off.....and yes its BAD...taking the other off after a cig and a bottle of water...calling Stillen and RT..to see what they say

 

I just called stillen..I have to send them back to them and they send them to RT .It will take for ever so Im going to get Kinetix pipes with resonators....see if the tinny rasp goes away