After having my fuel pump replaced, my car was running really sluggish, had massive power loss and ran really terrible. I found out that the problem was clogged catalytic converters. Apparently the filaments inside were tearing apart. My mechanic informed me that he cleared out the debris and clogging and told me the car was good to drive. The check engine light is back on and the cats produce a spurting or "putputputputputput" noise on idle and make more noise upon acceleration. I also smell exhaust fumes every once in a while. Any ideas on what to do now?

 

If your cats were clogged and all he did was clear it out and did not replace the cat your check engine light is on because the cat is no longer functioning as designed and the putputput noise you describe sounds like an exhaust leak from where ever he pulled apart the exhaust to get inside the cats. The exhaust smell would be due to the fact that your cats are no longer functioning right as well as the potential exhaust leak. Go back to your mechanic and tell him to fix it right. Any good mechanic would have known that gutting the cat was gonna cause issues.

 

Should always try to create a relationship with the most reputable mustang shop in area and use them when you can't accomplish a specific task. It's always much cheaper that way. They know what they are doing, they do it quickly & correctly and lastly they get to know your car fairly well. really comes into play when you decide to get a tuner and can get dyno tunes from them and with exhaust work, They will never say "no, can't do it" and they know what's best. American Muscle has Pypes and SLP cats for sell Stainless Works sells a great compact one too. Good luck.

 

Could be a leak but the cats actually muffle a lot of the exhaust sound. If you hollow out the honeycomb that's inside you don't have that noise suppression anymore just a big empty chamber that will give you that leak sound. New cats are expensive so he was saving you money but should have explained the situation to you. You should be able to get MIL eliminators or a tuner chip that will turn off the warning for less than new cats will cost.

 

He cant possibly access all four cats without cutting the midpipe open and at that point why not replace them?

Also there are no "filaments" inside, it is a solid ceramic block with small holes in it, simply put.

There are three major types of cat failure, melting, crumbling and clogging, all of which require a replacement. The latter of the three can be cleaned to an extent but you are only buying time.

I think you may have been taken for a wallet ride.

 

Not necessarily. We don't know what was done as the op really isn't familiar enough with this subject to know what to ask or explain what was done.
What I hear is there was bad cat (maybe more than 1) that broke up and was clogging the pipe. Depending how bad and which one(s) you can shove a rod down the pipe and break it all out. If you can't access it then you just cut open the cat, gut it and then weld it back up. If the noise is an exhaust leak its probably from where it was welded back up.
And not to bust ***** but what you listed are the types of failures, not the cause of the failure. Except in the case of a crumbling honeycomb, that will cause the pipe to get clogged up. The other case is when the holes in the ceramic honeycomb itself will clog which can happen quickly if you are running rich for to long.

 

Yeah, I worded it a little wrong, but...
My many previous posts on this subject show that its poor wording and not poor knowledge, everyone can make a grammar mistake here and there that changes the meaning of a sentence completly.

Change "Causes to" to "types of" and you get correct wording. I am not going to say its ball breaking because someone that doesnt know enough would take that wrong, so its good to at least catch it and elaborate on it.

The failure still doesnt line up with this type of ceramic block.

Here is my take on it, they are going to tell us exactly what the mechanic said because they have such limited knowledge on the matter.

If the mechanic were to repair it in such a way then he would have to tell him/her that he did because he was removing part of the emissions system. Florida may be a little different by those respects but they are still governed to need catalytic converters per federal requirements which in this case the op would still have 1 but they would still need to be notified of the removal of one.

As far as the exhaust leak goes, the mechanic may have not put he midpipe on secure enough or like you said he did end up cutting the midpipe open.

Chase could you give us a run down of what your repair bill says and if you can, get us a couple pics from the underside of your car, of the exhaust where your feet would go?

Also, to save you more time and money with this problem I suggest looking for a low mile used midpipe to pick up and have put in.

Used will run anywhere from $100-220 dollars but scrap value is about $160 right now so try to use that to negotiate a higher price down.

Check craigslist, great place to shop.

 

I only point it out because you clearly take the time to answer in a readable way. The info was good.

That's what makes it hard to trust what they 'think' they hear. For example I had a facebook friend describe her problem as being the "cadillac convertor".

Yes it is, and every state is different but none are the regulation hell hole that is CA. FL has no emissions inspections at all. In many states the more rural areas don't need to have emissions inspections either. America is still out there if you look hard enough:-)

 

lol, I fell into the cadillac catagory too, as a kid thats what I thought my dad said when he would talk about them. It wasnt till I said something about it back to him that he corrected me, and he is life long a marine mechanic with auto on the side as a 2nd. x_x

My dad was always the hard *** when it came to working on anything, do it myself and go get him on the really hard tech crap, otherwise no help with the simple crap.

Anyways, I hope the OP comes back with some more info for us to try to help him/her, we really just need more info here. :/