Stolen Catalytic Converter

Gdetrailer wrote:

ferndaleflyer wrote:
If you have no emissions inspections who knows or cares if you have a straight pipe. I have 2 pickups that haven’t had converters in years.

Most states have SOME "form" of checking/testing emissions, operating without ALL emission related equipment in place AND operating can be a hassle.

Myself, I am lucky to be just outside a county that DOES do full emissions testing, my county only requires the safety inspection mechanics to merely check to make sure cats are not missing.

As far as a vehicle operating fine without Cats, you obviously do not have a newer modern emission system or you have chipped your vehicle to bypass emissions.

OPs system is on a 2003 V10, 2003 typically will only have upstream O2 sensors which are before the cats, it may appear to "work fine" without cats but the reality is without having the back pressure of the cats those sensors will report back to the engine computer INCORRECT oxygen levels. The upstream O2 sensors are what the engine computer uses to detect the fuel mixture information. This WILL affect the fuel trim which can lead to an overly "rich" fuel mixture or an overly "lean" fuel mixture. This results in burning excessive fuel (dropping mileage) and if overly lean the engine will run excessively hot and possibly damage the engine.

Many vehicles sold specifically for California before 2003 CAN have upstream AND downstream O2 sensors and without a cat in place and operating it WILL cause a check engine light to stay lit..

I know emissions systems were changed between 2003 and 2006 and our 2006 5.4 V8 had BOTH upstream and downstream O2 sensors and I can assure you, ANY malfunction of the upstream or downstream 02 sensors CAN AND WILL affect the engines performance and mileage plus set the check engine light.. Been there, done that..

As far as cats, generics are not all that expensive considering the cost of a vehicle, we paid less than $250 per cat for generics (2006 5.4 had TWO cats, one for each bank).. The generic replacements work fine, we had no issue with them..

OPs 2003, the thieves may have done the OP a favor, that is within the yrs of cats known to suffer with the rattle of death in which the internal cat structure would fail and start rattling until it clogs..