HELP clogged catalytic converter question?

Question

Finally got my Bronco ll to the shop and was told its the cc.Mechanic assures me that the black smoke, intermittant sputtering/ stalling and clogged sound under the hood all point to clogged converter.At $300, total cost i say what the hell why not.But Im not convinced... Anyone had a converter go bad? what are the signs?I thought it would run sluggish all of the time and mine doesnt.Also how is the converter linked to the o2 sensor? should i replace this too?

I HAVE priced a CC and $300 is accurate.An aftermarket CC is less than $100-150.I trust my mechanic, ive been going to him for years.I do not think he would intentionally rip me off.He actually referred me to the muffler shop next to his and charged me zip for his evaluation.That is not the issue...

Thanks.Although i wouldnt rule out the head gasket theory, it definately doesnt explain the loss of power or the sputtering stalling.Ive had a blown gasket before and the only major syptoms i had were the oil and smoke.My Dad changed the oil again and it looks good.The car had been sitting over a year before i bought it last month...

Answer 1

It sounds like the problem, and yes they do clog up. The money sounds about right also. The 02 sensor senses the burned gasses, and if the converter is clogged it will be getting a false reading. Hopefully the mechanic will stand behind his work and solve your problem without any more expense

Answer 2

Use of a leaded gasoline will clog a Catalytic Converter. There may be an additive that you can add to your gas tank that will clear it.. Before you spend that kind of money on a guess, you might try
runnign the car without it. I will depend upon your mechanical expertise, I would try an additive firest. I had a fauty converter that did not have a diverter plate installed by the manufacturer. The diverter inside the converter is used to distribute the exhaust gasses over the entire converter. It developed a bad clog at the entry to the gasses.
My truck only developed a back pressure that slowed down my top speed. It did not backfire or cause any engine misses. I took and Iron fence pipe and pounded a hole right through the converter and put it back on, No trouble after that. (I took out a core sample, as it were) But then, I am a very clever fellow. Black smoke is a sign of a mixture that is much too rich. Usually those Oxygen sensors witll make it run too lean. Your check engine light should have indicated a problem. If it did not, you may have an on board computer problem, lousing up the input information and causing faulty running. Approach mechanich with caution. A guess is not what you need and it really points to the Oxygen sensor.

Answer 3

I once has a 1985 Buick Riviera with a clogged CC. The car lost a lot of power. It would barely climb hills. The acceleration was very sluggish, and my top speed was only 40 MPH before the engine overheated from the exhaust going back into the engine. Then it got worse and 25 MPH was my top speed. It got worse gas mileage than a Hummer.

My car never sputtered, and it only stalled when it overheated the one time.

Answer 4

I'm just a backyard mechanic but I would assume that if the Cat is clogged that it would heat up. This would be noticeable by checking it for glowing red at night in the dark. Just a thought..........

Here's another thought, your previous questions states oil getting dirty too fast. Check for blown head gasket. Even if it is not getting into the oil and turning it milky Grey it could be pumping out your exhaust causing rapid disintegration of exhaust components and would explain missing due to water getting into the cylinders.

Answer 5

the o2 sensor genarally is the beginning of the problems with the catylitic converter. tha converter gets clogged from poorly burned combustion materials( gasoline and oxygen/ oil sometimes too) the o2 sensor is supposed to catch the problem and correct it so the air/ fuel ratio is calculated by the cars computer correctly(assuming the vehicle has fuel injection and computer is working as it should be.) But, ASSUMING JUST MAKES AN *** OUT OF U AND ME.

Answer 6

If your converter is plugged up, it is possible that if could actually melt the O2 sensor. You will need to get it replaced ASAP.

I would try to talk the mechanic into just putting in straight pipes instead of putting the converter back in. (assuming that your state does not have inspections)

If your converter is still in one piece, if they try to charge you for a new one, make sure that they put a new one in. I know of a few mechanics that will charge for the new one, while just cleaning the old one off with brake cleaner. (this will work like that, and most people do not check)

Answer 7

It could be a cat. I would just whack it and the muffler and call it good. the 02 sensor probably isn't connected to the cat but it's purpose is to tell the vehicles computer if it is running rich or lean and the the computer can adjust the air fuel ratio accordingly.

Answer 8

At $300 I can tell you he is NOT replacing the cat at all, they are much more expensive than that to have replaced. I would suggest you do two things: 1) get a computer readout done. and 2) get a second opinion from a different mechanic.

This could be much more than a cat problem. I'm not trying to scare you, I'm trying to save you money before you (perhaps) spend it needlessly on a cat fix.

And I'd definately ask that mechanic EXACTLY what it is he is going to do for $300.....that is very important!

Answer 9

ha ha thats funny because my mom just took her 72 mustang in and had i tested for emisions because we just moved to utah and they failed her because her cat. was clogged and letting out to much pollution and she didnt know what to do so she was talking to my uncle and he said to put transmission fluid in her gas tank to help unclog it and clean it out well she did it and believe it or not it actually past emisons testing i hope this helps you and if not good luck anyway!!!!!!!