O.k.. Here I go again. Been helped by some nice guys here before. So I am back. Question. Can you reallly put some laquer thinner into the fuel syetem to help clean catalytic converter without doing any harm to the system, i.e., the pump, the injectors and the engine. I saw this on youtube. But really? I just don't have the funds right now to buy a new one. All things point to the cat con being clogged. And taking it off to gut it is my thinking. but will the laquer thinner by me some time so I don't have to take it off. I believe it's pretty damn clogged. And thanks to Hanky and GreaseMark and Hayapower for helping me narrow my search into this problem.

 

Just a little follow up.
How did you verify that the converter was clogged?
Have never heard of the lacquer thinner move , so won't comment on that.

 

Don't do it at all if you any doubt at all just cut it out and put a straight pipe in it's place. it won't pass any emissions test when you do it but if you don't get caught then what's the harm ? That will get you by until you can replace the cat.

 

Deduction. That's how I assume the catcon. The engine produces power and there are no vaccuum leaks. I started using top tier fuel and added some Mystery Marvel oil to the oil and cleaned the throttle body with a spray cleaner. After that , I experiecnced more lack of throttle. O.k., given that. I replaced air filter and then the O2 sensor. The one before the catcon. And I noticed it was original. Well it was stamped with Ford markings. And it was dented as if a rock had hit it. It was crunched in about halfway. So, my thinking is, since it was damaged, who knows when. It was sending a bad signal to PCM. And causing a wrong air/fuel mixture, unbeknownced to the previous owner and over time build up occurred. And the cleaners and better gas I added caused more contaminants into the exhaust system furthering the clog. I'm just taking a shot in the dark and going to pull it and gut it. There may be other problems within. But this is a good start. And no I am not going to do the laquer thinner thing. Sounded dumb, was just curious. I'm gutting it. We don't have smog test. Here they just check to make sure the catcon is there.

 

You didn't state the year vehicle, but I can gather it is an OBDII system you have on the vehicle. You can gut the converter, but you will learn that vehicles with the OBDII system don't like to have the emission items messed with since that is what the system is all about. The check eng lite will probably come on and all sorts of crazy things start happening. It may run better when cold, but when it warms up it has a way of letting you know it's not happy. With the price of gas these days, eventually, it will have been cheaper to replace the converter.

 

One really easy way to check for a plugged exhaust on these cars is to monitor the DPFE voltage on acelleration. If it spikes above 2.5 or so volts for over a second, then that will tell you pretty conclusively that something is amiss in the exhaust system.
However, there is a really easy, foolproof way to know for sure. Unbolt the exhaust at the headers and run it around the block. If the performace increaseses dramatically, then there you go. It will set codes (who cares?) and will run the fuel system rich, but if the car runs much better, there is no other test that will tell you as quickly as that.

 

On some other forum I read that you can remove the 1st O2 sensor, and attach an air pressure gauge. If you get more than a 1.5 or 2 PSI reading, it's clogged. The old fashioned vacuum gauges would actually read mechanical fuel pump pressure (on carbureted cars).

The PSI reading may be off, but it is an easy enough test.

Here's a Youtube video: How to check your vehicle's catalytic converter. - YouTube

 

Word of warning: if you gut the cat (your choice), it will always fail the catalyst efficency monitor, and set a P0420 code. Just a warning.
However, if you don't care and don't have to get it emmissions tested, it's your choice.