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Cadillac Repair/catalytic converter


removed both converters . Welded in straight pipes. Ck engine comes on as it should. What can I do to turn/reset the light for this signal without interfering with all other trouble codes except the bad converter codes.?          

I hear one can install a certain size resister in line, another fix is a dummy conver can be installed.

Both fixes would be 100X cheaper than reinstalling very expensive Cat Converters!  Thank youn    IT IS 2003 CTS


I have no idea if those purported fixes work. There are many on the Internet that shoot their mouths off about things that have no way of working. All I can say is that you can try it and see what happens, however there is almost always some kind of collateral damage with the so-called fixes because the vehicle was just not engineered for these fixes and to run without the cats.

What you also need to worry about if taken in for a simple oil change, there may be someone that rats on you because it is a federal crime to run the vehicle on the road without the cats. I understand the cost issue. Our Mercedes has 4 and you would not believe the cost even for after market.

Here is what I know. The computer system controls the efficiency of the engine and transmission. With everything working correctly it is in what is known as closed loop. When the emissions light is on and codes are coming up, the computer goes into open loop. Open loop is bad for the engine, because it will run richer or leaner depending on the situation, will effect gas mileage, performance and engine damage can occur.

I have not seen a cat bypassed since the 70's when we did it to run regular leaded gasoline or if we were trying to diagnose a plugged cat. I have not run across a question over the last 15 years of answering questions on this site with your situation.

Obviously, something has to be done to get the engine so it is running as designed. I would think your O2 sensor would be setting off a code as well. You also need to remember that these trouble codes will cascade. You may start of with a cat code, an )2 code, which will set other codes and problems off.
Ten there is the back pressure issue. The cats rom my understanding have back pressure, which you now have removed with straight pipes. I seriously do not know if you can trick the sensors to  have the computer function as designed to get the engine to run properly.

In essence by installing straight pipes on the vehicle, you have changed the engineering of the vehicle.

I would be very interested to know if those so-called fixes work for you.

As I said, there are so many people out there full of crap. I know my limitations. I only will give accurate information, because I don't want some poor guy to go to so much effort on something I told him that flat out didn't work.

There are idiots out there tat will tell a person anything. In my case, I have seen so much misinformation on auto theft methods or bypassing transponders and most of it simply is inaccurate.
One such place is the makers of the "Plug" at A so called anti theft device from the 70's and they brag of millions installed and not one stolen. Of course they can't prove that, but people are expected to believe it. They would give imaginary (as fact) details about how simple it was to bypass a factory transponder by just junping some wires. True? Of course not, but some people would believe it because everything on the Internet is true--lol

I am very knowledgeable on many repairs to Cadillacs, but your situation alters the factory design.

I wish you luck with this and as I said, please get back to me if what you are being told is true, because you never know, I may get someone else in the sme situation.

Good luck!
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Rob Painter


Alarm system questions cannot be answered on this forum. These systems are not what I can answer. Without being physically at the vehicle and not knowing what kind of electrical service has been done on the vehicle, there is no possible way to give an accurate answer over the internet. My expertise is in Ignition/key based anti-theft systems. These issues include GM VATS (resistor chip in key blade) PASSLOCK (MRD)-ignition lock rotation based, no special ignition key and the PKIII Transponder (computer chip in key) systems. These systems are not alarm based and are integral with the starting of the engine. This is why I cannot diagnose alarm problems without physically looking at the vehicle: Alarm systems are a completely different annimal than ignition key/lock based anti-theft system. Many alarm questions come from vehicles 10 years old, and since older, many hands that had been involved over the years.I am an expert in all GM factory (ignition/key based)systems. Alarm system questions pose to many situations beyond my knowledge as to what has been done to the vehicle over the years. Some guy may have actually wired the stereo into the alarm system. Who knows? Over my past 30 years in vehicle wiring repair, I have seen unbelievable wiring disaters done by guys that consider themselves "mechanics." I have seen stereos and alarms intalled using surgical tape. I have seen modules burn up, un-fused circuits, wiring jambed between the doors and even lamp cord used for a starter kill. To answer alarm questions over the internet without examining the vehicle is like asking; What does it take to remove a dent?


Education/Credentials-ASE certified. 11 years with a GM dealer and 17 years with a repair facility dealing with only the repair of theft recovered vehicles.

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