So I just bought a used 2002 F150. It had a check engine light, but the PO had a reader and showed me that it just had an O2 sensor out - no big deal. A little research on the exact code shows that it is the downstream passenger side sensor. In preparation for getting a replacement and installing it, I decided to check and make sure I'd be able to get to it. I consulted a couple websites and my repair manual and got down underneath. It turns out that the reason the sensor isn't working is because it isn't *there*....

Judging by the missing catalytic converter and the piece of pipe welded in it's place, some junky cut it out some time ago, and the owner had the piece of pipe welded in as a cheap fix.

So I put it to you guys and gals: how big of a deal is it to run with 1 cat and 3 O2 sensors? Is it really going to impact performance/mileage/emissions, or can I do without? If I can do without, is it possible to clear the code permanently so that the check engine light goes away?

Thanks!

 

Depending on which state you live in, replacing the cat may be required by law. If you have no state inspections or smog laws, you can run w/o any cats at all. There are delete kits available that allow you to run only one O2 sensor per side but you'll have to have a shop reprogram the computer to eliminate the CEL and remove the secondary O2 sensors from the fuel mixture program.

 

Alright, thanks! I'm pretty sure there aren't any smog test laws here (Oklahoma), so I should be good on that front. Just have to figure out who can reprogram the computer.

 

Start by finding the Cat deleat kit (Summit Racing.com? or RockAuto.com) and see if you can confirm programming requirements. Maybe use their "Chat" window. I would find a speed shop or a small auto repair shop to do your computer adjustments. You can use the term "Reflash" your computer when you inquire if they can do the work.

 

Cats are required in all 50 states... that being said...not all 50 states check for them...