O2 sensor covered in carbon

**JackieTA** · 06-19-2015, 05:46 AM

I just replaced both front o2 sensors on my LS1. It has headers, no catalytic converters. The old O2 sensors were COVERED with carbon. I assume from the car running rich. What other things could
Be damaged from the car loading up? Anything else I should clean or replace? It's running good now, but I don't want to ruin my new o2's if there is existing build up somewhere else. Thanks!

***SMWS6TA*** · 06-19-2015, 07:20 AM

How long has it been since a tune up?

Cleaning the MAF would also help as well as the TB where the IAC is. In the TB on the intake side you will see the IAC port, a lot of times it gets gum up with oil blowby. It doesn't hurt to pull it off and with carb cleaner clean it good.

**2002ssslp** · 06-19-2015, 04:16 PM

Don't forget to change the plugs as well.

**pajeff02** · 06-20-2015, 04:41 AM

An exhaust leak above the O2 senders can induce a false lean condition and result in over fueling. Another possibility is leaky fuel injectors that are dumping more fuel than called for into the cylinders. Crusty air filter is another possibility. Get a read on the spark plugs and then let's go from there.